FIELD

The present disclosure relates to a robotic arm. More specifically, the present disclosure relates to a gripper for grabbing or gripping a target object.

BACKGROUND

The background information herein below relates to the present disclosure but is not necessarily prior art.

Robots are used in many applications including manufacturing, tactical and law enforcement. A robot includes all the device necessary to perform the desired functions. Each robot typically includes at least one extensible and maneuverable arm. And, each arm is configured with some type of gripping mechanism that can be used to hold and, if desired, release a target object or other items to be transported by the robot.

Typically, conventional grippers of a robotic device use two double four-bar mechanisms for actuation and holding a target object. The second double four-bar mechanism acts like an elastic tendon for straightening the finger when it opens up. However, the presence of two double four-bar mechanisms makes the fingers stubby and assembly complex. Also, the digits of the conventional grippers are not in the same proportion as human finger digits.

Further, the fingers of the conventional grippers are actuated by a customized spur gear mechanism, i.e. specially cut concave -convex spur gear pairs; therefore, auto-locking or selflocking of the fingers is difficult in a given position without a braking system. Also, with the conventional gripper, it is difficult to customize or manipulate the inter-digit angle in open configuration of the fingers.

Furthermore, due to lack of proper sensing architecture in the gripper, sometimes while grabbing even a small positional displacement of the target object away from its initial location might prevent successfully grabbing by the gripper, and may result in damage to the target object and/or the gripper. Also, in absence of the sensing architecture in the conventional grippers, it is also difficult to predict a gripping force to hold the target object, which can cause the target object to slip from the gripper when transporting the target object from one place to another. Therefore, there is felt a need for a gripper for a robotic device that alleviates the aforementioned drawbacks.

OBJECTS

Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:

It is an object of the present disclosure to ameliorate one or more problems of the prior art or to at least provide a useful alternative.

An object of the present disclosure is to provide a gripper for a robotic device.

Another object of the present disclosure is to provide a gripper for a robotic device that is scalable to any size.

Still another object of the present disclosure is to provide a gripper for a robotic device that is light in weight.

Yet another object of the present disclosure is to provide a gripper of a robotic device that hold and grasp a target object like a human-hand.

Another object of the present disclosure is to provide a gripper for a robotic device that is selflocking.

Another object of the present disclosure is to provide a gripper for a robotic device that facilitates the straightness of a finger in an extreme position.

Yet another object of the present disclosure is to provide a gripper for a robotic device that senses the presence of a target object.

Still another object of the present disclosure is to provide a gripper for a robotic device that senses the lifting force for a target object.

Yet another object of the present disclosure is to provide a gripper for a robotic device that sense the shape, size, force and distance of a target object.

Another object of the present disclosure is to provide a gripper for a robotic device that senses surface texture, colour hardness or softness of a target object.

Another object of the present disclosure is to provide a gripper for a robotic device with a single 4-bar link mechanism. Still another object of the present disclosure is to provide a gripper for a robotic device that firmly holds a target object.

Yet another object of the present disclosure is to provide grippers for a robotic device that avoids damage to a target object while grabbing.

Still another object of the present disclosure is to provide a gripper for a robotic device that can be controlled remotely.

Yet another object of the present disclosure is to provide a robotic device that has detachable fingers.

Still another object of the present disclosure is to provide a robotic device which is operated based on data collected over cloud services or cloud storage.

Yet another object of the present disclosure is to provide a robotic device that runs on Artificial Intelligence (Al) and Machine Learning (ML) based model.

Still another object of the present disclosure is to provide a robotic device which gets trained based on the data collected over cloud storage.

Other objects and advantages of the present disclosure will be more apparent from the following description when read in conjunction with the accompanying figures, which are not intended to limit the scope of the present disclosure.

SUMMARY

The present disclosure envisages a finger of a gripper for a robotic device. The finger is configured to be operatively mounted on an operative portion of a housing of the gripper in communication with a plurality of drive motors. The finger comprises an enclosure; a tilt link is configured with the enclosure and is further configured to be mounted in communication with at least one of the drive motors; a shaft is configured with worm and mounted within the hollow cavity of the enclosure, the shaft is configured to be in communication with at least one of the drive motors; a plurality of digits configured to be mounted with each other to define at least one finger of the gripper; a plurality of links is configured to be mounted on an operative portion of the plurality of digits and is configured to engage with the worm of the shaft to enable mobility of the plurality of digits in an operative configuration of the gripper. In an embodiment, the plurality of digits includes a bottom digit, at least one intermediate digit and a top digit. The digits are configured to be movably mounted end to end to define at least one of the gripper fingers.

In an embodiment, the fingers include a plurality of biasing means and is configured to be operatively mounted in between the bottom digit and the at least one intermediate digit as well as the at least one intermediate digit and the top digit. The biasing means is configured to hold the digits of the finger in an operative straighten position.

In an embodiment, the plurality of links includes a first link, a second link, a third link, and a fourth link. The at least one of the links are configured to be operatively mounted to at least one of the plurality of digits. The bottom digit, the first link, the second link and the third link are configured to join to form a first 4-bar link mechanism to actuate at least the bottom digit in an operative configuration of the gripper. The at least one of intermediate digit, the third link, the fourth link and the top link are configured to join to form a second 4-bar link mechanism to actuate the at least one intermediate digit and the top digit in an operative configuration of the gripper.

In an embodiment, the first 4-bar link mechanism is configured to be in communication with the second 4-bar link mechanism.

In an embodiment, the bottom digit is configured to be mounted on a flange portion extending from an operative edge of the enclosure.

Further, the gripper includes at least one first drive motor and at least one second drive motor. The tilt link of the enclosure is configured to be in communication with the at least one first drive motor by means of a rotor link to provide tilting motion to at least one of the fingers within a pre-defined tilting angle. The shaft of the enclosure is configured to be in communication with the at least one second drive motor to receive the driving motion of the second drive motor in an operative configuration of the gripper.

In an embodiment, the first link is configured to be mounted with a worm gear. The worm gear is configured to be engaged with the worm of the shaft to enable planar moment to at least one of the fingers in an operative configuration of the gripper.

In an embodiment, each of the finger is configured to be in communication with each of the second drive motor to independently actuate each of the finger. In an embodiment, the fingers include a plurality of sensors and is configured to be mounted on an operative portion of at least one of the plurality of digits of the finger. The plurality of sensors is configured to be in communication with at least one control module provided within the device, the gripper is configured to actuate based on signal sensed by the plurality of sensors.

In an embodiment, the plurality of sensors are selected from a group of proximity sensors, and is configured to sense the presence of the target object within a certain range without any physical contact, the proximity sensor includes hall sensor, encoder, limit inductive Proximity Sensors, Capacitive Proximity Sensors, Ultrasonic Proximity Sensors, Optical Proximity Sensors, Hall Effect Proximity Sensors, Magnetic Proximity Sensors, Photoelectric Proximity Sensors, Infrared (IR) Proximity Sensors, Micro-Optical Proximity Sensors, Time- of-Flight (ToF) Proximity Sensors, Multi-Modal Proximity Sensors or any combination thereof.

In an embodiment, the plurality of sensors are selected from a group of force sensors, and is configured to sense the gripping force required to grip the target object in an operative configuration of the device, the force sensors are selected from a group of Load Cell, Strain Gauge, Pressure Transducer, Torque Sensor, Tension Sensor, Compression Sensor, Shear Sensor, Piezoelectric Sensor, Strain Transducer, Force Transducer, Dynamic Force Sensor, Static Force Sensor, Strain Gauge Load Cell or any combination thereof.

In an embodiment, at least one of the plurality of digits is provided with a rubberized gripping surface for firm gripping of the target object.

Further, the present disclosure also envisages the gripper for the robotic device. The gripper is configured to interact with at least one target object to enable gripping of the target object. The gripper comprises: a housing configured to enclose different electrical and mechanical components therein; a plurality of fingers defined by operatively joining a plurality of digits and is configured to be mounted on an operative portion of the housing; a plurality of links is configured to be mounted on an operative portion of the plurality of digits of the fingers and further configured to act as motion transmission link between different digits of the finger; at least one first drive motor configured to be mounted within the housing and further configured to provide tilting motion to at least one of the finger within a pre-defined tilting angle range; at least one second drive motor configured to be mounted within the housing and further configured to provide planar moment to at least one of the finger; and at least one control module configured to be in communication with the plurality of fingers, the first drive motor and the second drive motor and further configured to control the actuation of the finger in an operative configuration of the device.

In an embodiment, the housing is configured with a plurality of cut-outs to accommodate and mount the fingers therein. An operative portion of the housing is configured with a plurality of sensors selected from a group consisting of camera sensor or optical sensor and a range sensor or proximity sensor.

In an embodiment, the second drive motor is configured to be in communication with a set of spur gear, the spur gears is configured to be in communication with the shaft to transfer motion from the second drive motor to the finger.

In an embodiment, the first drive motor and the second drive motor is selected from a group consisting of servo motors or DC motors or any driving means.

In an embodiment, the digits of the fingers are configured with a plurality of sensors, the sensors are selected from a group consisting of force sensors, pressure sensor, Load Cell, Strain Gauge, Pressure Transducer, Torque Sensor, tilt angle sensors, IR sensors, range sensors, limit switches or any combination thereof.

In an embodiment, the control module is configured with a set of machine leaning and artificial intelligence (AI/ML) based rules and is further configured to guide and actuate the fingers based on global gripper data to grasp and hold the target object based on loop-based feedback. The control module is configured to be in communication with at least one cloud storage unit by means of a different communication network, the cloud storage unit is configured to access and store global cloud data of the fingers related to grasping and holding of a particular target object.

In an embodiment, the gripper is configured to be remotely operated by means of a remote device.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWING

The gripper for a robotic device of the present disclosure will now be described with the help of the accompanying drawing, in which: Figure la illustrates a perspective view of a conventional robotic finger (Prior art);

Figure lb illustrate a perspective view of four four-bar link mechanism of the conventional robotics finger (prior art);

Figure 2 illustrates a robotic device configured with a plurality of robotic fingers in accordance with an embodiment of the present disclosure;

Figure 3a illustrates a robotic finger with a plurality of digits in accordance with an embodiment of the present disclosure;

Figure 3b illustrates a robotic finger with an exploded view of plurality of digits in accordance with an embodiment of the present disclosure;

Figure 3c illustrates a perspective view of engagement of worm gear with the worm of the robotic finger in accordance with an embodiment of the present disclosure;

Figure 3d illustrates a perspective view of positioning of biasing member of a gripper finger in accordance with an embodiment of the present disclosure;

Figure 4 illustrates a gripper finger enclosure and a worm gear arrangement for the actuation of plurality of fingers;

Figure 5 illustrates an assembly of a first drive motor with a first robotic finger and a second robotic finger for tilting in accordance with an embodiment of the present disclosure;

Figure 6 illustrates an arrangement of a plurality of stepped gears for motion transmission from a second drive motor to a first finger, a second finger, and a third finger in accordance with an embodiment of the present disclosure;

Figure 7 illustrates grabbing of a target object by means of digits of a plurality of fingers in accordance with an embodiment of the present disclosure;

Figure 8 illustrates a sequence of control actions involved in gripping a target object in accordance with an embodiment of the present disclosure;

Figure 9 illustrates a sequence of control actions involved in tilting a target object in accordance with an embodiment of the present disclosure; Figure 10 illustrates an ML model for autonomous controlling of a plurality of fingers for gripping a target object in accordance with an embodiment of the present disclosure;

Figure 11 illustrates an ML model for autonomous controlling of a plurality of fingers for tilting a target object in accordance with an embodiment of the present disclosure; Figure 12 illustrates a flow diagram for remote control actuation of a robotic gripper;

Figure 13 illustrates a feedback circuit for actuating and controlling the operation of a first drive motor and a second drive motor in accordance with an embodiment of the present disclosure;

Figure 14 illustrates a feedback circuit in communication with a Microcontroller to operate a first drive motor and a second drive motor in accordance with an embodiment of the present disclosure;

Figure 15 illustrates the different orientation of the tip, configured in the top digit; and

Figure 16 illustrates an elastic membrane or elastic net attached to a plurality of fingers.

LIST OF REFERENCE NUMERALS USED IN DETAILED DESCRIPTION AND DRAWING

200 - Gripper of Present Disclosure

20- Conventional finger

20a - First Finger of Present Disclosure

20b - Second Finger of Present Disclosure

20c - Third Finger of Present Disclosure

22a’- Fingertip of conventional finger

22a - Top Digit

22b - Intermediate digit

22c - Bottom Digit - First Link a- Worm Gear - Second Link - Third Link - Fourth Link - First Biasing Means - Second Biasing Means - Pressure / Force Sensor - Camera Sensor - Finger Tilt Sensor - Range Sensor - Gripper Housing - First Drive Motor - Second Drive Motor - Rotor Link - First Tilt Link - Second Tilt Link - Third Tilt Link - First Mounting Frame - First Finger enclosure - Second Finger enclosure - Third Finger enclosure - Shaft - First Stepped Shaft - Second Stepped Shaft a - First Spur Gear b - Second Spur Gear c - Third Spur Gear - Worm Tip of top digit Hinge point - Electronic Circuit - Encoder - Micro Controller or control modulea - First Drive Microcontroller b - Second Drive Microcontroller - Cloud Storage unit - Communication Network - Hall Sensor - Remote System - Limit Switch First Triggered - Limit Switch Second Triggered 96 - Target Object

98 - Elastic web/ Elastic net or /elastic membrane

100’- Conventional four bar link mechanism

100- First four-bar link mechanism

102- Second four-bar link mechanism

DETAILED DESCRIPTION

Embodiments, of the present disclosure, will now be described with reference to the accompanying drawing.

Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details, are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.

The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, elements, modules, units, and/or components, but do not forbid the presence or addition of one or more other features, elements, components, and/or groups thereof.

Typically, the conventional fingers (20’) of the robotic gripper for a robotic device use two double four-bar mechanisms i.e. four four-bar link mechanisms (100’) for actuation and holding a target object. The second double four-bar mechanism on a particular digit of the conventional finger (20’) acts like an elastic tendon for straightening the finger when it opens up. However, the presence of two double four-bar mechanisms on the particular digit makes the fingers stubby and assembly complex. Also, the digits of the conventional grippers are not in the same proportion as human finger digits which makes handling of the target object difficult.

Further, the conventional fingers (20’) of the conventional grippers are actuated by a customized spur gear mechanism, i.e. specially cut concave-convex spur gear pairs; therefore, auto-locking or self-locking of the fingers is difficult in a given position without a braking system. Also, with the conventional gripper, it is difficult to customize or manipulate the inter-digit angle especially the top digit (22a’) in the open configuration of the conventional fingers (20’). Figure la illustrates a perspective view of a conventional robotic finger; and Figure lb illustrate a perspective view of four four-bar link mechanism of the conventional robotics finger.

To overcome the aforementioned drawbacks, the present disclosure envisages a finger of a robotic gripper 200 for a robotic device to grab a target object 96. The finger 20a, 20b, 20c is configured to be operatively mounted on an operative portion of a housing 42 of the gripper in communication with a plurality of drive motors such that at least one finger 20a, 20b, 20c interacts with the target object 96 to enable gripping of the target object 96. The robotic gripper 200 is configured to be mounted on an arm for manoeuvring. The robotic gripper 200 is now being described with reference to Figure 2 to Figure 16.

The finger 20a, 20b, 20c of the gripper 200 comprises: an enclosure defined by a circular aperture and a hollow cavity configured therein, the enclosure 58, 60, 62 configured to be operatively mounted on an operative portion of the housing 42; a tilt link configured with the enclosure and is further configured to be mounted in communication with at least one of the drive motors, the tilt link configured to impart tilting motion to the enclosure in an operative configuration of the device; a shaft configured with worm of a pre-defined pitch and further configured to be mounted within the hollow cavity of the enclosure, the shaft is configured to be in communication with at least one of the drive motors; a plurality of digits configured to be mounted with each other to define at least one finger of the gripper and further configured to be operatively mounted to the enclosure; and a plurality of links are configured to be mounted on an operative portion of the plurality of digits, an operative portion of one of the link configured to engage with the worm of the shaft to enable mobility of the plurality of digits in an operative configuration of the gripper. A first embodiment of the present disclosure will now be described with reference to Figure 2, Figure 3a-3d, Figure 4, Figure 5 and Figure 6. The robotic gripper 200 comprises the gripper housing 42 on which a plurality of fingers 20a, 20b, and 20c are detachably mounted, and actuated by means of the plurality of drive motors 44, 46.

In an embodiment, the plurality of drive motors includes at least one first drive motor 44 and at least one second drive motor 46. The first drive motor 44 and the second drive motor 46 are configured to transmit motion by means of worm and worm gear arrangements 72, 24a.

In an embodiment, the first drive motor 44 and the second drive motor 46 are selected from a group consisting of a servo motor with or without an embedded encoder.

The robotic gripper 200 provides access for a first finger enclosure 58, a second finger enclosure 60, and a third finger enclosure 62 in which a first finger 20a, a second finger 20b, and a third finger 20c are being respectively mounted. The first, second and, third finger enclosure 58, 60, and 62 (as shown in Figure 1) have a circular aperture with a hollow cavity configured therein. The hollow cavity houses the shaft with a worm arrangement 72, and bearings. The outer circular aperture enables the first finger 20a and the second finger 20b to tilt while maintaining a dustproof and gap-free contact with the housing cut-outs as shown in the figure 1. The Figure 2 illustrates the robotic device configured with the plurality of robotic fingers 20a, 20b, 20c in accordance with an embodiment of the present disclosure;

Further, the first drive motor 44 is configured to provide tilting action to the fingers whereas the second drive motor 46 is configured to provide planer movement to the fingers 20a, 20b, and 20c. The first drive motor 44 is mounted to a first mounting frame 56 and configured with a rotor link 48, a first tilt link 50, a pair of second tilt link 52, and a pair of third tilt link 54. The rotor link 48 is engaged to a shaft 64 of the first drive motor 44. The two operative ends of the rotor link 48 are engaged to the first end of each of the second tilt link 52. And the other end of each of the second tilt link 52 is engaged to an operative end of each of the third tilt link 54. Each of the third links 54 is attached to the outer circular aperture of the first finger enclosure 58 and the second finger enclosure 60 which provides tilting action to the first finger 20a and the second finger 20b with the rotation of the first drive motor 44.

In an embodiment, one or more first drive motor 44 can be mounted separately to the first finger 20a and the second finger 20b to provide tilting action independently of each other. In another embodiment, each of the finger 20a, 20b, 20c is configured to be in communication with each of the second drive motor 46 to independently actuate each of the finger 20a, 20b, 20c.

The rotor link 48 and the worm gear arrangement 72 together allow the first finger 20a and the second finger 20b to simultaneously rotate inward to grasp the target object and tilt sideways either outward or inward to adapt to the size of the target object i.e. biplanar rotational movement is allowed using the worm gear arrangement 72 with the rotor link mechanisms. Therefore, it allows two modes of simultaneous rotation. The first mode is when the rotational axis of the worm gear 72 is perpendicular to the worm axis and the second mode is when the worm gear “tilts” i.e. slides on the surface of the worm such that the centre of the worm gear rotates around the centre of the worm or worm axis with the axis of rotation of the worm gear coinciding with the axis of the worm. This allows the gripper to grasp and adapt to the size of the target object 96 being grasped using only two motors.

Further, the second drive motor 46 is provided with a first stepped shaft 66. The stepped shaft is defined by a shape in which first operative end is a regular shaft that is coupled and driven by worm arrangement on the middle finger, a second operative end is hollow cylindrical portion that co-axially fits on spur gear 70a. A screw is used to connect this hollow end with the spur gear with the main shaft so that all three shafts rotate simultaneously. The operative portion of second end of the stepped shaft is configured with a first spur gear 70a thereon. The first spur gear 70a is configured to drive a second spur gear 70b and a third spur gear 70c, configured on a second stepped shaft 68 and the shaft 64, respectively. An operative end of each of the pair of shafts 64 is configured with the worm gear to provide planer movement to the first finger 20a, the second finger 20b, and the third finger 20c, respectively.

In an embodiment, the spur gear has a central projecting hub. Such gears were used because a) they are readily available and b) the third finger hollow shaft fits on this hub and drives the third finger.

In an embodiment, the first spur gear 70a drives the second spur gear 70b, and the third spur gear 70c. Therefore, the second spur gear 70b drives the worm gear associated with the first finger 20a and thereby actuates the first finger 20a, and the third spur gear 70c drives the worm gear associated with the second finger 20b and thereby actuates the second finger 20b. Also, the first spur gear 70a drives the worm gear associated with the third finger 20c and thereby actuates the third finger 20c. The first finger 20a, the second finger 20b and the third finger 20c thus rotate or curl in and out perpendicular to the plane containing the first spur gear 70a, the second spur gear 70b, and the third spur gear 70c respectively.

Further, the fingers 20a, 20b, and 20c of the robotic gripper 200 are composed of a plurality of digits, i.e. a top digit 22a, at least one intermediate digit 22b, and a bottom digit 22c. The digits 22a, 22b, and 22c are provided with a flange portion to attach an operative portion (end to end) of one digit with another digit. The lengths of each digit are in proportion to the digit’s length of a human finger, therefore the fingers 20a, 20b, 20c of the robotic gripper 200 acts like the human finger for grabbing and holding the target object. Figure 3a illustrates a robotic finger with a plurality of digits; Figure 3b illustrates a robotic finger with an exploded view of plurality of digits; Figure 3c illustrates a perspective view of engagement of worm gear with the worm gear arrangement of robotic finger; and Figure 3d illustrates a perspective view of positioning of biasing member of a gripper finger in accordance with an embodiment of the present disclosure.

The figure 4 illustrates a gripper finger enclosure and a worm gear arrangement for the actuation of plurality of fingers. The Figure 5 illustrates an assembly of the first drive motor with the first robotic finger and the second robotic finger for tilting in accordance with an embodiment of the present disclosure. The Figure 6 illustrates an arrangement of plurality of stepped pulley for motion transmission from the second drive motor to the first finger, the second finger and the third finger in accordance with an embodiment of the present disclosure.

In one embodiment, the digits 22a, 22b, 22c are attached with one-another by means of a plurality of fasteners selected from a group consisting of a rivet, threaded screw, threaded inter-screw, a nut-bolt or any combination thereof.

Further, the different digits 22a, 22b, 22c of the fingers 20a, 20b, 20c are being actuated by means of a plurality of links. The bottom digit 22b is being mounted with a first link 24, a second link 26, and a third link 28, to thereby define a first four-bar link mechanism with a first operative end and a second operative end. The first operative end is configured to engage with an operative end of the at least one intermediate digit flange portion. And, the intermediate digit 22b is being mounted with the third link 28, a fourth link 30, the top digit 22a; to thereby define a second four-bar link mechanism. In an embodiment, the bottom digit 22c, the first link 24, the second link 26 and the third link 28 are configured to join to form a first four-bar link mechanism 100 to actuate at least the bottom digit in an operative configuration of the gripper.

In an embodiment, the at least one of intermediate digit 22b, the third link 28, the fourth link 30 and the top link 28 are configured to join to form a second four-bar link mechanism 102 to actuate the at least one intermediate digit and the top digit in an operative configuration of the gripper. The first four-bar link mechanism 100 is configured to be in communication with the second four-bar link mechanism 102.

In an embodiment, the bottom digit 22c is configured to be mounted on a flange portion extending from an operative edge of the enclosure.

Further, the finger includes a plurality of biasing means .i.e a first biasing means 32 is installed in- between the bottom digit 22c and the intermediate digit 22b, and a second biasing means 34 is installed in-between the intermediate digit 22b and the top digit 22a. Advantageously, each finger 20a, 20b, and 20c includes only two four-bar link mechanisms 100, 102 for their actuation and control. The biasing means 32, 34 is configured to hold the digits of the finger in an operative straighten position.

In an embodiment, the top digit 22a, the intermediate digit 22b, and the bottom digit 22c, are made from a material selected from metals, alloys, polymeric materials or a mixture thereof.

In another embodiment, the first link 24, the second link 26, the third link 28 and the fourth link 30 are made from a material selected from metals, alloys, polymeric materials or a mixture thereof.

In another embodiment, the first biasing means 32 and the second biasing means 34 is a selected from a compression member or a torsion spring.

The first four-bar link mechanism 100 is used to actuate the fingers 20a, 20b, and 20c in such a way that when the worm rotates, the worm gear in mesh with the worm rotates. When the worm gear rotates counter clockwise (as shown in the Figure 3), it actuates the first link 24 which is attached to the worm gear. The first link 24 actuates the second link 26, which subsequently activates the third link 28. The third link 28 in turn actuates the bottom digit 22c. Thus, the bottom digit 22a the first link 24, the second link 26 and the third link 28 together forms the first four-bar mechanism 100.

The third link 28 actuates the fourth link 30 that in turn actuates the intermediate digit 22b and the top digit 22c. Thus, the third link 28, the fourth link 30, the intermediate digit 22b and the top digit 22c together forms the second four-bar link mechanism 102. Further, the presence of the first biasing means 32 between the bottom digit 22c and the intermediate digit 22b makes both the digits remain parallel to each other until an obstacle is encountered by at least one of the digits of the fingers 20a, 20b, 20c. If the bottom digit 22c encounters an obstacle surface, the intermediate digit 22b continues moving inward and curls around the obstacle surface. Figure 7 illustrates grabbing of the target object by means of the digits of the plurality of fingers in accordance with an embodiment of the present disclosure.

Similarly, the presence of the second biasing means 34 between the intermediate digit 22b and the top digit 22c makes the intermediate digit 22b and the top digit 22a remain parallel to each other until an obstacle is encountered by the intermediate digit 22b. Once the intermediate digit 22b encounters an obstacle surface, the top digit 22a continues curling inward until it hits the obstacle surface itself. Therefore, the first and the second biasing means 32, 34 removes the requirement of the another set of four-bar link mechanism to straighten the fingers 20a, 20b, 20c. When the first link 24 moves outward i.e. clockwise, the finger opens up as the first link 24 actuates the second link 26, subsequently the second link 26 actuates the third link 28 and the third link 28 actuates the fourth link 30 to open up the bottom, the central and the top digits 22c, 22b, and 22a. Thus, the first and the second biasing means 32, 34 ensure that the fingers get straighten after opening up.

Advantageously, the two four-bar link mechanisms 100, 102 along with inter-digit biasing means 32, 34 ensures that the fingers 20a, 20b, 20c does not require another set of double four-bar link mechanism to adapt to the counter of the target object being grasped by the finger and the fingers straighten when opening up. Also, the worm and worm gear actuation mechanism ensure that the fingers are auto-locked in given position when the drive motor is not powering the worm or the fingers.

In an embodiment, the angle between the digits 22a, 22b, and 22c can be customized or manipulated by changing the angle between digits 22a, 22b, and 22c while installing the inter-digit biasing means. In another embodiment, the digit proportions for the plurality of the digits 22a, 22b, 22c, and the link lengths can be adjusted and can be different than human finger digit proportions as per the application requirements.

In another embodiment, the digits 22a, 22b, 22c of the fingers 20a, 20b, 20c can have different shapes and sizes based on the application requirements.

In an embodiment, the top digit 22a has a movable fingertip with at least one biasing member attached thereon. The biasing member allows the grasping of the target objects 96 without exerting excessive grabbing force. The fingertip is also configured with tilting arrangement to facilitate tilting grasping.

In an embodiment, the biasing member 32, 34 is a torsional spring or a biaxially mounted torsion springs. The two mutually perpendicular torsion springs hinge for tilting fingertip in two directions to facilitate tilting grip of the target objects and grasping grip of the target objects.

The present configuration provides Self-locking capability due to availability of the worm gear arrangement. Therefore, even when the power is cut off, the target object not fall off. In an embodiment, the worm-worm gear arrangement facilitates self-locking of finger and said digits in an operative configuration of the gripper 200.

In another embodiment, the fingers of the gripper can have more than three digits based on the application requirements. Therefore, if there are “n” numbers of digits in one finger, then it will have “n-1” numbers of four bar mechanism for their actuation and control.

In another embodiment, multiple motors can be used for independent sideways tilting of the first finger 20a and the second finger 20b instead of using a single motor.

In another embodiment, the grabbing action and the tilting action can be performed simultaneously.

In a preferred embodiment, firstly the grabbing action is performed followed by the tilting action or vice versa.

Further, a plurality of camera sensors 38, and range sensors 40 are configured on the housing of the robotic gripper 200. The camera sensors 38 and the range sensors 40 are configured to detect the distance of the target object being grasped from the gripper surface, and the size and shape of the target object. Therefore, this data is used to open the fingers 20a, 20b, and 20c to accommodate the target object being grasped and to close the fingers 20a, 20b, and 20c appropriately to confirm to the surface contours of the target object being grasped. Figure 8 illustrates a sequence of control actions involved in the gripping of the target object in accordance with an embodiment of the present disclosure. Figure 9 illustrates a sequence of control actions involved in tilting of the target object in accordance with an embodiment of the present disclosure.

In an embodiment, the object distance, shape, and size detection can be predicted by means of one or more camera sensor, without the requirements of the range sensors.

In another embodiment, the grabbing of the target object is done by taking inputs from both the camera 38 and/or the range sensors 40.

Further, the fingers 20a, 20b, 20c includes a plurality of sensors and is configured to be mounted on an operative portion of at least one of the plurality of digits of the finger. The plurality of sensors are configured to be in communication with at least one control module 82 provided within the device, the gripper is configured to actuate based on signal sensed by the plurality of sensors.

In an embodiment, the plurality of sensors (40) are selected from a group of proximity sensors, and is configured to sense the presence of the target object within a certain range without any physical contact, the proximity sensor includes hall sensor, encoder, limit inductive Proximity Sensors, Capacitive Proximity Sensors, Ultrasonic Proximity Sensors, Optical Proximity Sensors, Hall Effect Proximity Sensors, Magnetic Proximity Sensors, Photoelectric Proximity Sensors, Infrared (IR) Proximity Sensors, Micro-Optical Proximity Sensors, Time-of-Flight (ToF) Proximity Sensors, Multi-Modal Proximity Sensors or any combination thereof.

In another embodiment, the plurality of sensors are selected from a group of force sensors, and is configured to sense the gripping force required to grip the target object in an operative configuration of said device, the force sensors are selected from a group of Load Cell, Strain Gauge, Pressure Transducer, Torque Sensor, Tension Sensor, Compression Sensor, Shear Sensor, Piezoelectric Sensor, Strain Transducer, Force Transducer, Dynamic Force Sensor, Static Force Sensor, Strain Gauge Load Cell or any combination thereof. In an embodiment, the plurality of force sensors 36 are mounted on each of the digits of each finger 20a, 20b, 20c to sense the lifting force required. The amount of force being applied and the instructions given by a robot microcontroller when to increase, lower, or cease clamping force by the first drive motor 44 and the second drive motor 46 can be calculated based upon the reaction force exerted by the target object to be grasped by the fingers 20a, 20b, and 20c. This reaction force is detected using the force or pressure sensor which is configured on each of the digits of the fingers 20a, 20b, and 20c.

In an embodiment, the at least one of the plurality of digits 22a, 22b, 22c is provided with a rubberized gripping surface for firm gripping of the target object 96.

In second embodiment, the present disclosure also envisages the gripper 200 for a robotic device. The gripper 200 is configured to interact with at least one target object 96 to enable gripping of the target object. The gripper 200 comprises: the housing 42 which is configured to enclose different electrical and mechanical components therein; the plurality of fingers 20a, 20b, 20c defined by operatively joining the plurality of digits 22a, 22b, 22c and configured to be mounted on an operative portion of the housing 42; the plurality of links are configured to be mounted on an operative portion of the plurality of digits of the fingers and is further configured to act as motion transmission link between different digits of the finger; the at least one first drive motor is configured to be mounted within the housing and is further configured to provide tilting motion to at least one of the finger within a pre-defined tilting angle range; the at least one second drive motor configured to be mounted within the housing and further configured to provide planar moment to at least one of the finger; and the at least one control module configured to be in communication with the plurality of fingers, the first drive motor 44 and the second drive motor 46 and further configured to control the actuation of the finger in an operative configuration of the device.

The control module or the microcontroller 82 or miniaturized computer is either installed within the body of the gripper 200 or is provided as a separate encased unit. The model that runs on the microcontroller 82 employs loop-based feedback, regression, or recursive learning or Artificial Intelligence/ Machine Learning (AI/ML) rules is used to instruct the gripper 200 to grasp and hold different types of target objects. The data input required for the model can be supplied by the force or pressure sensors 36, encoders 80, tilt angle sensors 39, camera sensors 38, IR sensors, range sensors 40, and limit switches 92, and 94 present on the gripper 200. In an embodiment, the control module (82) is configured to be detachable mounted from the body of the gripper.

In another embodiment, the electronics and microcontroller module may be fitted with the gripper 200 that houses the fingers and the drive mechanism itself.

In another embodiment, the control module may be mounted separately from the gripper and can communicate with the main gripper via wired communication and/or wireless communication.

In first embodiment, the data and AI/ML model, both are stored on hardware. Therefore, the data collected by the plurality of sensors, the control action of the drive motors is processed locally by the control module to facilitate the grasping action or finger movement etc. The AI/ML model runs on the microcontroller or the control module to teach the gripper to enable holding of various kinds of target objects.

In second embodiment, the data is stored on cloud and the AI/ML models runs locally. Therefore, the data collected by the plurality of sensors, motor control action instructions, grasping action or the finger movement etc. is collected on cloud. This data is made available to all grippers connected (via secure authentication) to this cloud data repository. The AI/ML model runs locally for each gripper microcontroller that has access to this data to teach the gripper to enable holding of various kinds of target objects.

In third embodiment, Data collected from sensors, motor control action instructions, grasping action/finger movement etc. is collected on cloud. AI/ML model also runs on cloud and uses this data to create a “learning” (AI/ML model weights and parameters) on how to grasp and manipulate different kinds of objects. Each gripper can connect securely to this cloud data store and AI/ML model/leaming service. Each connected gripper can then download the “learning” in form of an algorithm. This learned algorithm running on the gripper microcontroller generates instructions to undertake optimal object grasping. The AI/ML generates instruction to undertake optimal object grasping and passes them to each individual gripper.

In fourth embodiment, Data is collected locally on robot microcontroller and AI/ML model runs in cloud. Data is passed on to AI/ML cloud service via secure connection and the AI/ML cloud service passes back the “learning” back to the gripper to undertake gripping action or else can pass direct control.

In fifth embodiment, both collected data and AI/ML model reside on cloud. The AI/ML algo instructs the gripper on how to hold the object in real time by giving instructions to the gripper microcontroller. In this case the “learning” is not passed on to the gripper only gripping instructions are provided.

In an embodiment, the control module (82) is configured with Al or ML rules which is either located within the control module or remotely stored. Figure 10 illustrates an ML model for autonomous controlling of the plurality of fingers 20a, 20b, 20c for gripping the target object in accordance with an embodiment of the present disclosure. As illustrated in figure 9, the microcontroller 82 is configured to control the second drive motor 46 in accordance with the control prediction generated by machine learning (ML) model, where the machine learning (ML) model is performing the operation based on the data received from a global cloud data/cloud storage/cloud service 84 and generates the control prediction and further the microcontroller 82 perform the control actions on the second drive motor 46. The global cloud data/cloud storage/cloud service 84 is collected and stored the attributes and parameters for encoder 80, the force/pressure sensors 36, the camera sensors 38, the range sensors 40, and the current state of the first limit switch 92 and the second limit switch 94.

In an embodiment, the control module 82 is configured to be in communication with at least one cloud storage unit by means of a different communication network. The cloud storage unit 84 is configured to access and store global cloud data of the fingers related to grasping and holding of a particular target object 96.

Figure 11 illustrates the Al/ ML model for autonomous controlling of the plurality of fingers for tilting the target object in accordance with an embodiment of the present disclosure. As illustrated in figure 10, the microcontroller 82 is configured to control the first drive motor 44 in accordance with the control prediction generated by the machine learning (ML) model, where the machine learning (ML) model is performing the operation based on the data received from a global cloud data/cloud storage/cloud service 84 and generates the control prediction and further the microcontroller 82 perform the control actions on first drive motor 44. The global cloud data/cloud storage/cloud service 84 is collected and stored the attributes and parameters for the encoder 80, the force/pressure sensors 36, the first camera sensors 38, the first range sensors 40, and the current state of the first limit switch 92 and the second limit switch 94.

In an embodiment, the microcontroller 82 is an Internet of Things (loT) enabled.

In another embodiment, the microcontroller 82 is in communication with a cloud service 84 by means of a different communication network 86. The communication network includes Digital or Analog Input/Output, Recommended Standard 232 (RS232), Recommended Standard 422 (RS422), Recommended Standard 485 (RS485), Controller Area Network (CAN), Transmission Control Protocol/Intemet Protocol (TCP/IP), Hyper Text Transfer Protocol Secure (HTTPS), Transport Layer Security/Secure Sockets Layer (TLS/SSL), Wireless Fidelity (Wi-Fi), Bluetooth, interface connection protocol (I2C), Ethernet, etc. Data from different grippers deployed all over the world is collected on the cloud service/ cloud storage 84 and shared or available for consumption by all those grippers. The Artificial Intelligence/ Machine Learning (AI/ML) model running on the microcontroller 82 of the gripper 200 uses the global gripper data to teach the gripper to grab and manipulate the target objects.

In another embodiment, the robotic device includes another cloud service that runs on Artificial Intelligence/ Machine Learning (AI/ML) model on the cloud having the global cloud data and instructs every connected gripper 200 about how to grab and manipulate the target objects. Since, the different robotic grippers across the globe are synched through the AI/ML model, therefore, once a first robotic gripper grasp the target object at one place, the data will get stored over the cloud storage and if required same data can be retrieved and used by another robotic gripper present at any other place to grab and lifting the target object.

In another embodiment, the gripper 200 can be instructed to grip and manipulate the target object by using the data collected over the cloud service/ cloud storage 84 from the different sensors outside of the gripper, i.e. the sensors placed on adjacent tools, sensors placed in a factory in another country, etc. Figure 12 illustrates a flow diagram for remote control actuation of the robotic gripper.

Figure 13 illustrates a feedback circuit for actuating and controlling the operation of the first drive motor 44 and the second drive motor 46 in accordance with an embodiment of the present disclosure. As illustrated, the actuation and controlling operation of the first drive motor 44 and the second drive motor 46 are based on the received feedback. The remote device 90 transmits instructions and receives responses and error codes from the microcontroller 82. The microcontroller 82 executes instructions that receive from the remote device 90 and accordingly provides a response/error code to the remote device 90. The communication is formed between the remote device 90 and the microcontroller 82 via the communication network that includes Recommended Standard 232 (RS232), Recommended Standard 422 (RS422), Recommended Standard 485 (RS485), Controller Area Network (CAN), Transmission Control Protocol/Intemet Protocol (TCP/IP), Hyper Text Transfer Protocol Secure (HTTPS), Transport Layer Security/Secure Sockets Layer (TLS/SSL), Wireless Fidelity (Wi-Fi), Bluetooth, interface connection protocol (I2C), Ethernet, etc. The microcontroller 82 receives the input/output signals from pressure/force sensor 36 via the communication network. The microcontroller 82 actuates and controlling of the operation of the first drive motor 44 and the second drive motor 46, where the first drive microcontroller 82a is configured to operate and control the first drive motor 44, and the second drive microcontroller 82b is configured to operate and control the second drive motor. The first drive microcontroller 82a and second drive microcontroller 82b receive feedback from the encoder 80 and the hall sensor 88 and further actuate and control the operation of the first drive motor 44 and the second drive motor 46 accordingly. The feedback is collected via the communication network.

Figure 14 illustrates a feedback circuit in communication with a Microcontroller to operate the first drive motor 44 and the second drive motor 46 in accordance with an embodiment of the present disclosure. As illustrated, the actuation and controlling operation of the first drive motor 44 and the second drive motor 46 are based on the received feedback. The remote device 90 transmits instructions and receives responses and error codes from the microcontroller 82. The microcontroller 82 executes instructions that receive from the remote device 90 and accordingly provides a response/error code to the remote device 90. The communication is formed between remote device 90 and the microcontroller 82 via a communication network that includes RS232, RS422, RS485, CAN, TCP/IP, HTTPS, TLS/SSL, Wi-Fi, Bluetooth, Ethernet, etc. The microcontroller 82 receives the input/output signals from pressure/force sensor 36 via the communication network. The microcontroller 82 actuates and controlling of the operation of the first drive motor 44 and the second drive motor 46, where the first drive microcontroller 82a is configured to operate and control the first drive motor 44, and the second drive microcontroller 82b is configured to operate and control the second drive motor. The microcontroller 82 receives feedback from the encoder 80 and the hall sensor 88 and is further configured to actuate 82 and control the operation of the first drive motor 44 and the second drive motor 46 accordingly. The feedback is collected via the communication network.

In an embodiment, the gripper 200 can have a plurality of fingers 20a, 20b, 20c as per requirement. Multiple fingers can be connected in such a way that they are actuated by the same drive motor. The placement angles between various fingers is adjusted by putting universal couplings on the drive shafts of each finger. Multiple rotor links mechanisms can be used to tilt different fingers. In an embodiment, the gripper can have more than three fingers depending on one requirement.

In an embodiment, the different types of fingers with different shapes and size, with different number of digits and digit dimensions can be used with the gripper of the present disclosure.

In an embodiment, the fingers (20a, 20b, 20c) of the robotic gripper (200) is detachably mounted to the housing (42) and coupled to the first drive motor (44).

In an embodiment, the fingers (20a, 20b, 20c) of the robotic gripper (200) is configured for bi-axial tilting within the housing (42).

In an embodiment, the fingers (20a, 20b, 20c) of the robotic gripper (200) is configured for single -axial tilting within the housing (42).

In another embodiment, the top digit 22a of the finger 20a, 20b, 20c is configured with a rotatable tip 74 with a torsion spring attached therewith. The torsion spring is attached at a hinge point 76. The tip 74 of the finger is configured to provide firm gripping to hold a thin or ultrathin object such as glass, lens, papers etc. Therefore, while holding the thin or the ultrathin objects, the tip 74 rotates under the action of the torsion spring and provides the firm gripping and when the tip 74 leaves the object, it comes back to its original position under the biasing force of the torsion spring. Thus, the tip 74 provided on the top digit 22a swivels around its mean position. Figure 15 illustrates the different orientation of the tip which is configured in the top digit.

In another embodiment, a plurality of fingers 20a, 20b, 20c can be mounted on the gripper 200. Each finger can have an independent first drive motor 44 and an independent second drive motor 46. In an embodiment, the gripper 200 is configured with the modular body with detachable and replaceable fingers 20a, 20b, 20c. The fingers can be outfitted without the need to open up the gripper main body.

In an embodiment, the gripper payload to gripper weight ration can be >= 1.

In another embodiment, the fingers 20a, 20b, 20c of the robotic gripper 200 are configured to removably attach an elastic membrane, or elastic web or an elastic net 98 in between them. The elastic membranes or elastic webs or the nets 98 forms a pocket or bag like structure that enable the robotic gripper 200 a better grabbing of the target object 96 without dropping it. The elastic membranes or the webs or the nets 98 encompasses the gripped target object 96 and prevent it from slipping out of the gripper 200. Also, the Elastic web like membranes 98 folds outward when the fingers of the robotic gripper closes, so that the elastic web don’t get entangled with the fingers when they are closed. Figure 16 illustrates an elastic membrane or elastic net attached to a plurality of fingers. An exemplified pseudo-code depicting the device for the robotic gripper for grabbing or gripping the target object is given below:

Class Gripper

{

Remote device()

{

Instruction()

{

Send_inst=Sends instruction;

Rec_res= receives response;

Err_res= error code;

System. out.println(“Send Instruction, &Send_insf ’);

System. out.println(“receive response, &Rec_res”);

System. out.println(“error code, &Err_res”); }}

Sensor()

{

Send_signls= Send sensors details;

}

Microcontroller!)

{

Call .Instruction!) ;

Call. Sensor();

Rec_inst= Receives instruction from remote device;

Exe_inst=Executes instruction;

Control!)

{

First drive controller!)

{

Call.Microcontroller();

Actuate and control first drive motor 82a;

Feed_enc=Collect feedback by encoder;

Feed_hall=Collect feedback by hall sensors;

System. out.println(“encoder feedback, & Feed_enc”);

System. out.println(“hall sensor feedback code, & Feed_hall”); }

Second drive controller ()

{

Call.Microcontroller();

Actuate and control second drive motor 82b;

Feed_enc=Collect feedback by encoder;

Feed_hall=Collect feedback by hall sensors;

System. out.println(“encoder feedback, & Feed_enc”);

System. out.println(“hall sensor feedback code, & Feed_hall”);

}

If (Feed enc ==1 && Feed_hall==l)

{ then transmit encoder feedback and hall sensor feedback to the microcontroller 82; transmit encoder feedback and hall sensor feedback to first drive controller 82a and Second drive controller 82b;

}

Else()

{

Call.first drive controller ();

Call. Second drive controller ();

} }

}

}

The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.

TECHNICAL ADVANCES AND ECONOMICAL SIGNIFICANCE

The present disclosure described herein above has several technical advantages including, but not limited to, the realization of a gripper for a robotic device, that:

• is scalable to the desired size based on the application requirement;

• is light in weight as the robotic gripper uses only two four-bar link mechanism for the actuation of different digits of the fingers;

• grasp a target object like a human hand;

• provides self-locking of the finger as the motion between the fingers are being transmitted by worm-worm gear arrangement;

• provides tilting of the fingers in range from +90° to -90°;

• facilitates the straightness of the finger in an extreme position, thereby the gripper provides a relatively larger degree of compilation;

• senses the presence of a target object and the lifting force for a target object; sense the shape, size, and distance of a target object and thus avoid the damage to the target object while grabbing; has detachable fingers based on the application requirements; provides comparatively better grabbing of the target object by means of an elastic net;

• is operated based on data collected over the cloud services;

• sense the shape, size, force and distance of a target object; and

• runs on Artificial Intelligence (Al) and Machine Learning (ML) based model.

The foregoing description of the specific embodiments so fully reveals the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, or group of elements, but not the exclusion of any other element, or group of elements.

While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.