TECHNICAL FIELD

The invention relates to; multiple degrees of freedom, innovative seven degrees of freedom manipulator consisting of two spherical one linear actuators, which can be effectively used in robotic and simulator mechanisms and applications, and the original spherical motor as a part of the system.

PREVIOUS TECHNIC

A modem robotic system usually consists of a mechanical manipulator, an end processor, a microprocessor-based controller, a computer, and internal and external sensors. Robots can be classified based on their features such as workspace, kinematic structure, degrees of freedom, control structure, and hardware. The most basic form of classification is to categorize the robots based on their degrees of freedom. Ideally, a manipulator should have 6 degrees of freedom to freely manipulate an object in three-dimensional space. From this point of view, a robot is called a general purpose robot if it has 6 degrees of freedom, a residual robot if it has more than 6 degrees of freedom, and a complete robot if it has less than 6 degrees of freedom. Another type of classification is based on its kinematic structure. If a robot has an open kinematic chain loop, it is called series, if it has a closed kinematic chain loop, it is called parallel, if it has both, it is called a hybrid robot.

Actors of robot, manipulator or simulator systems; are grouped as electrical, hydraulic or pneumatic driven. In most systems, DC, AC-servo or stepper motors are used because they are cleaner, cheaper, quieter, and relatively easy to control. Hydraulic drives are advantageous over electric motors as they have high response speed and torque. Thus, systems with hydraulic actuators are primarily used to lift heavy loads. The disadvantages of these hydraulic driven systems are that they require much more peripheral equipment such as oil leakage problems, pump, reducer, oil tank and they are noisy. Pneumatic robots are cheap and simple, but cannot be fully controlled because air is a compressible gas. As a result, pneumatically driven robotic systems are used in application-insensitive automation processes and more limited lines of businesses such as selection/screening applications. The workspace of a manipulator is defined as the volume of the coordinate set (space) accessible to the end handler. The maximum working area is the volume of space accessible to each point by the end processor in at least one direction. The effective workspace is the volume of space that can be accessed by the end processor at every point in all possible routings. The effective workspace is a subset of the maximum workspace.

Most industrial robots have six degrees of freedom or less in the current applications. These robots are generally classified as kinematics based on the first three joints of the arm (R-rotation or P-prismatic) used to manipulate position, while the rest of the wrist-related joints are used for controlling orientation. The majority of these robots (manipulators) fall into one of five geometric types: Cartesian (PPP), Cylindrical (RPP), Spherical (RRP), SCARA (RRP), Articulated (RRR). Each of these five manipulator arms are serial robots. The sixth different class of manipulators is called parallel robot. In a parallel manipulator, as mentioned earlier, the links are arranged in a closed kinematic chain rather than an open kinematic chain.

The subject of the invention; the seven degrees of freedom manipulator system, consisting of two spherical one linear actuators, resembles to serial manipulators in terms of kinematics and resembles to parallel manipulators in terms of working space structure. However, the most important feature that distinguishes the invention from other systems and known techniques is that it reaches seven degrees of freedom with only three actuators and can be easily used in robotic/manipulator/simulator applications. In addition, the subject of the invention has an innovative design because it contains a unique spherical motor design that provides these advantages.

Disadvantages of prior technique robotic/manipulator/simulator systems:

• They must have as many actuators as degrees of freedom.

• The control process becomes more difficult and complex with the increase in the number of actuators.

• The inability to fully present economical and ergonomic designs proportional to the number of actuators.

In the industry, traditional electric motors are used as actuators to provide power for different purposes. The resulting motion is generally rotary motion on a single axis. The rotary motion can be moved to different axes or converted into linear motion with various machine elements. The system can be driven by using multiple actuators in case it is desired to move in different axes in more than one axes. Thanks to the use of spherical motors, it is possible to drive and control the system with a single actuator for up to three separate axes.

Spherical motors; it has come to the fore for the first time with the design of the induction motor in a structure consisting of a spherical rotor. The expectation from the spherical motor is that it moves with the same freedom in every axis. However, this complicates the control of the motor and makes it difficult to adapt its design to any system . In addition, in most spherical motor designs, torque cannot be obtained directly proportional to the size and weight of the motor. For example, the spherical motor, which is foreseen to be used in any robotic joint, should be able to move the joints together with its own load. Therefore, this can be achieved with simpler design and control by limiting movement. In some recent studies, spherical motor designs for discrete motion instead of integrated motion have been carried out.

In the novel design of the spherical motor, which is the most important part of the manipulator system, is the subject of the invention; while the outer sphere is the stator and the inner sphere is the rotor, the windings and cores are connected to the outer sphere, namely the stator. There are magnets on the rotor. If an electric current is supplied to any of the windings located in the stator, a magnetic field is created in that winding and attracts the magnet in the rotor. Accordingly, the desired motion can be obtained by giving electric current to the windings on that axis on which axis movement is desired.

Another inventive spherical motor used in the seven degrees of freedom manipulator system; it has a permanent magnet design that can move separately. The invention is the spherical motor, has a lighter and more modular design and can be used in any robot, manipulator or similar mechanism. Unlike other spherical motors in the known techniques, the bearing is provided with a multi-point ball mechanism between the two covers, and in this way, a more balanced movement of the rotor from the center or the rotor surface is provided compared to the bearing models.

Advantages of the inventive spherical motor according to known techniques:

• When compared to the known technique, there are 3 covers; lower, middle and upper, which provide both the bearing of the rotor and hold the 18 stators together in the spherical motor design that is the subject of the invention. • Since the multi-point ball mechanism is placed between the upper and lower covers of the motor, more balanced movement can be achieved from the center of the rotor or from the rotor surface compared to the spherical motor models with bearings. Surface bearing restricts the movement of the rotor and the design of the motor due to the position of the stator, friction and gaps in the contact surface. On the other hand, the center bearings inside the rotor take up extra weight and extra space, and can also affect the magnetic field. While the bedding from the cover opens a large area for the stator, it has no effect on the magnetic field. It provides great convenience in design and is quite light. The cover also fulfills the mechanical stopper function together with the connecting shaft on the rotor. In this way, any vertical mechanism can maintain its vertical position at a certain angle even if the motor is not running.

• Each coil in the motor is placed separately from each other and with this design, instead of using a complex algorithm to obtain a single resultant motion, the tilt and spin motions are separated from each other. In this way, motor control and design have become ergonomic and it is possible to obtain higher torque with lower energy. Each stator module consists of 3 coils, 2 tilt and 1 spin coils, and thanks to this modular structure, rotor and coils can be assembled/disassembled very easily.

• The stator system in the motor consists of a total of 18 coils, 6 spins in the middle layer and 12 tilts in the lower and upper layers. Tilt coils are 6 rows in 2 layers. Coils mutually push or pull in order to tilt the rotor in one direction. In this way, the control of the motor becomes easier and reduces the load on the equipment.

• It is possible to increase the magnetic flux effect with the bolts that act as the iron core in the coils and direct the magnetic flux.

• On the spherical rotor consisting of three layers; a total of 24 magnets are placed in cube-shaped dimensions of 10 x 10 x 10 mm with 8 magnets on each layer. This layout is compatible with the arrangement of the 12 tilt coils in the lower and upper layers and the 6 spin coils in the middle layer, and it enables the rotor to perform the tilt and spin motions more easily. In addition, an ergonomic spherical rotor design has been achieved in this way. BRIEF DESCRIPTION OF THE INVENTION

The subject of the invention; it is a seven degrees of freedom manipulator system consisting of two unique spherical motors and one linear actuator, which can be used in robotic and simulator mechanisms and has a more ergonomic and economical design compared to previous techniques. It is the completely original and innovative spherical motor design that enables the invention to reach seven degrees of freedom and have a design different from the literature with this feature.

According to literature review, the most important features that distinguish the invention from other systems and known techniques are;

• The manipulator system, which is the subject of the invention, reaches seven degrees of freedom with only three actuators and can be easily used in robotic/manipulator/simulator applications,

• It is possible to summarize the spherical motor design, which is the subject of the invention, as being completely different and original from the spherical motor designs in the literature.

THE LIST OF FIGURES

Figure 1. Front View of Top Plate Placed Seven Degrees of Freedom

Manipulator System Consisting of Two Spherical One Linear Actuators

Figure 2. Isometric View of Seven Degrees of Freedom Manipulator System with Top Plate Placed

Figure 3. Assembled View of Seven Degrees of Freedom Manipulator System with Robotic Gripper Placed

Figure 4. Exploded View of Seven Degrees of Freedom Manipulator System with Robotic Gripper Placed

Figure 5. Front View of Spherical Motor

Figure 6. Isometric View of the Spherical Motor

Figure 7. Top View of Spherical Motor

Figure 8. Sectional View of Spherical Motor

Figure 9. Disassembly View of Spherical Motor

Figure 10. Top Section View of Spherical Motor

Figure 11. Isometric Section View of Spherical Motor

Figure 12. Spherical Rotor Front View

Figure 13. Spherical Rotor Isometry View Figure 14. Bearing System Examples of Spherical Rotors

Figure 15. Display of Tilt and Spin Angles of Spherical Rotor

Figure 16. Layout Layers Illustration of Spherical Rotor Magnets and Coils

Figure 17. Display of Spherical Motor Spin Force and Torque

Figure 18. Display of Spherical Motor Tilt Force

Figure 19. Side View of the Coil

Figure 20. Isometric View of the Coil

Figure 21. Top View of the Coil

The cross numbers of the components that stated in the list of figures are given below;

1. Manipulator Fixing Table

2. Spherical Motor Fixing Part

3. Spherical Motor

3.1 . Spherical Motor Shaft

3.2. Spherical Rotor

3.2.1 Spherical Rotor Internal Mechanism

3.3. Bottom cover

3.4. Middle Cover Part

3.5. Top cover

3.6. Body Joining Bolt

3.7. Body Joining Nut

3.8. Air Duct

3.9. TiltCoils Core

3.10. Spinning Coils Core

3.11. Top Vent

3.12. Magnet On

3.13. Bearing Ball

3.14. Top Layer Tilt Coils

3.15. Middle Layer Spinning Coils

3.16. Bottom Layer Tilt Coils

3.17. Coil Insulation Reel

3.18. Enamel Coated Copper Wire

4. Linear Motor 4.1 . Linear Motor Shaft

5. Manipulator Simulator Table

6. Manipulator Robotic Gripper

DETAILED EXPLANATION OF THE INVENTION

The invention consists of six main parts: manipulator fixing table (1 ), spherical motor fixing part (2), spherical motor (3), linear motor (4), manipulator simulator table (5) and manipulator robotic gripper (6).

The main purpose of the invention is an innovative 7 degrees of freedom manipulator system consisting of two spherical one linear actuators, which can reach many degrees of freedom with fewer actuators, can be used in robotic and simulator applications and can be an alternative to known manipulator systems. When the previous techniques are examined, a system that can reach to seven degrees of freedom with only three actuators and is similar to the inventive manipulator system has not been encountered.

The manipulator system, which is the subject of the invention, consists of two spherical and one linear actuators, a fixed limb and a movable limb as a mechanism. The spherical motor (3) located under the manipulator is connected to the fixing table (1 ) with the spherical motor fixing part (2). Then the lower spherical motor (3) is fixed to the linear motor (4) by the spherical motor shaft (3.1 ). With this connection, the middle part of the manipulator is formed. Finally, the linear motor shaft (4.1 ) is combined with the other upper spherical motor (3). With the upper spherical motor shaft (3.1 ), the manipulator simulator table (5) or manipulator robotic gripper (6), which is located at the top of the manipulator and is described as a movable limb, is connected. In this way, the inventive manipulator system is formed. The manipulator achieves six degrees of freedom by driving two spherical motors of the same characteristics and design, located above and below the system, in three axes (x-y tilt and z spin). With the drive of the linear motor (4) located between the two motors, an additional degree of freedom is added to the system, and by this means, the manipulator reaches 7 degrees of freedom with 3 actuators. In Figure 1 -3, the general structure and logic of the manipulator are presented in detail. The invention can easily become a simulator with 7 degrees of freedom in case of using the manipulator simulator table (5), and a robotic system with 7 degrees of freedom in case of using the manipulator robotic gripper (6). In this way, a multi-degree of freedom and ergonomically designed manipulator system that allows different applications is presented to the literature.

The invention is a unique spherical motor (3), which provides the most important part of the manipulator system and can provide 6 degrees of freedom to the system; spherical motor shaft (3.1 ), spherical rotor (3.2) including spherical rotor inner mechanism (3.2.1 ), lower cover (3.3), middle cover part (3.4), upper cover (3.5), body joining bolt (3.6), body joining nut (3.7), air duct (3.8), tilt coils core (3.9), spin coils core (3.10), top vent (3.11 ), magnet (3.12), bearing ball (3.13), top layer tilt coils (3.14), middle layer spin coils (3.15) and bottom layer tilt coils (3.16), coil insulation reel (3.17) and enamel-coated copper wire (3.18) winding.

The spherical motor (3), which is the subject of the invention, consists of rotor and stator. Inside the spherical motor (3), there is the spherical rotor (3.2), which forms the rotor of the motor and has 24 magnets on it. This spherical rotor (3.2) consists of three layers as lower, middle and upper, and there are 8 magnets (3.12) at equal intervals in each layer. According to this layout and layer shape, there are 12 top layer tilt coils (3.14) and lower layer tilt coils (3.16), 6 middle layer spin coils (3.15), which are located inside the motor and form the stator part of the motor. Each coil is likewise composed of tilt coils core (3.9) and spin coils core (3.10), coil insulation reel (3.17) and enamel-coated copper wire (3.18) winding. The core function in all coils is provided by steel bolts and the magnetic flux effect in the stator system increases in this way. In addition, these bolts ensure that the coils are fixed to the middle cover part (3.4).

Top layer tilt coils (3.14) and bottom layer tilt coils (3.16) are 6 each in the lower and upper layer, and middle layer spin coils (3.15) are 6 in the middle layer, according to the spherical rotor geometry and magnet arrangement (3.12) has been placed. Briefly, there are 18 coils forming the stator part in the spherical motor (3) in total. The lower layer tilt coils (3.16) and the top layer tilt coils (3.14) enable the spherical rotor to make the tilt movement in the x and y axes. The middle layer spin coils (3.15) located in the middle layer constitute the rotational movement of the spherical rotor (3.2) around the z axis. The internal structure of the spherical motor (3) is protected by the hexagonal lower cover (3.3), the middle cover part (3.4) and the upper cover (3.5). These three cover pieces are connected by body coupling bolts (3.6) and nuts (3.7). The hexagonal cover geometry means that magnets (3.12) placed in the cube-shaped holes opened on the spherical rotor (3.2) and the upper layer tilt coils (3.14), middle layer spin coils (3.15) and lower layer tilt coils (3.16), which form the stator system, operate synchronized and in this way it ensures that the spherical rotor (3.2) can make the most optimum tilt and spin motions.

The spherical motor middle cover is formed by joining 6 modular interlocking middle cover parts (3.4). The purpose of this is to easily intervene in the spherical rotor (3.2) and stator coils without removing the entire cover system when there is a problem in the operation of the motor. The middle layer spin coils (3.15) are arranged in such a way that they come to the junctions of the middle cover parts (3.4) forming the middle cover, that is, to the corner parts of the hexagonal geometry. In addition, the ventilation channel (3.8) and the upper ventilation hole (3.11 ) are opened on the middle cover parts (3.4) and the upper cover (3.5), respectively, against the heating condition of the spherical motor (3). The tilt coils (3.14) in the stator system, the bottom tilt coils (3.16) and the middle layer spin coils (3.15) are fixed the modular middle cover parts (3.4) with the steel bolt type tilt coil core (3.9) and the spin coil core (3.10), respectively.

The spherical rotor (3.2), which is one of the most important parts of the spherical motor (3), is supported by a total of 12 bearing balls (3.13), 6 of which are placed inside the lower cover (3.3) and the upper cover (3.5). Balancing of the spherical rotor (3.2) and minimizing the friction forces are provided with this bearing method. On the inside of the spherical rotor (3.2), there is a spherical rotor inner mechanism (3.2.1 ) that ensures that the center of gravity does not deviate and is fixed to the spherical rotor shaft (3.1 ). The rotor shaft (3.1 ) connects the lower motor to the linear motor (4) and the upper motor to at least one of the manipulator simulator table (5) and robotic gripper (6). The spherical motor (3) with fixing part (2), is fixed to the fixed limbs of the system via the manipulator fixing plate (1 ), and it is fixed to the movable limbs with the manipulator simulator table (5) and the robotic holder (6) by at least one.

In short, the seven degrees of freedom manipulator system and the novel spherical motor which is the most important part of this system, are the innovative designs that are the subject of the invention. The manipulator system is suitable for use in different applications and can replace conventional manipulator or robotic systems of known technique. On the other hand the spherical motor has the feature of invention with its completely original design, different working strategy and applicability, which is not unique in the literature.