The invention relates to a method and guidance system for use of robot according to the preambles of the independent claims.

Especially in determining distance and in so called 3D- scanning of surroundings it is commonly known to utilize both sound and light operated sounding sensors, such as e.g. narrow or broad beam ultrasonic sensors and laser scanners.

Nowadays there are robots that are able to move and operate independently for a broad range of purposes . An example of one of these is an automatic personal robot, shown in patent application publication US 2007/0198129, is meant especially to further the conditions of an elderly person living alone. In this robot, there may be sensors of the most varied kinds in order to recognize e.g. smoke, temperature or carbon monoxide in the apartment, a monitoring automatism to monitor the condition of the elderly person or e.g. equipment needed to dispense or dose medications or to measure blood pressure or blood sugar. Furthermore, in the apparatus there may be e.g. a radio, an mp3- or a DVD- player or other devices that further the elderly person's functions or comfort, such as a reading light to help reading, a magnifying glass etc. With the robot, it is furthermore possible to control the apartment's lighting and electrical devices or to be in connection with the elderly person via a mobile phone connected to the robot. This robot is furthermore possible to be equipped with "arms" in order to carry out its functions, such as opening doors or cupboards, fetching items, using light- or on/off-buttons etc.

Especially in order to enable functioning of the above mentioned robot indoors, it comprises an automatic, machine vision technique based mapping arrangement of the indoors, which is carried out with a camera connected to the robot's data processing arrangement. Therefore it is possible for the robot to constantly observe its surroundings and move by a motor in a controlled manner with drive and turning pulleys therein. As the robot moves indoors, in order to avoid it bumping into furniture or walls, it is proposed in the application publication in question that in addition to machine vision, ultrasonic sensors or the like technique to be used, which in practice means e.g. so called short range approaching sensors crafted especially for the needs of the car industry.

The robot according to the above mentioned application publication is very versatile in its composition and functions due to its purpose, and therefore naturally very expensive to produce. This robot is also especially complex to control- in different kinds of indoor environments and utilizing circumstances requiring very comprehensive automation and data processing. Due to these reasons, this robot also requires regular service and maintenance in order to maintain its reliable functioning and accuracy in different functions. This device is however unnecessarily complex for simpler use, such as e.g. in open indoors or with a view to use in circumstances outdoors, where mapping of the surroundings based on machine vision is practically unnecessary. In addition, dust in circumstances^ outdoors or in dusty indoor circumstances, such as in indoor arenas for sports, maneges or on sand courts, would not enable a very long-term functioning of a camera based on machine vision without the need for repeated cleaning of the optics.

On the other hand, problems due to the purpose of ultrasonic sensors manufactured especially for the needs of car industry, are first of all especially in robot use, when detection from a few meters is required, a short detection distance, which is due to low transmission output of such sensors, and their very wide detection beam, which opens typically at an angle of even 120 degrees horizontally and 60 degrees vertically. Due to these reasons, independent monitoring of a target by a robot equipped with such sensors is practically not possible without the risk of the target getting out of sight of the robot. In order to eliminate this risk, it would require a very short monitoring distance, practically a few hundred millimeters at most, which would naturally bring about most heterogeneous accident risks _' On the other hand, the broad detection beam, both longitudinally and horizontally, of the type of approaching sensors mentioned above, produces a lot of distractions and a need for massive filtering of the measurement signals in order to differentiate relevant sig- nals . Filtering of the approaching sensor's signals is practically carried out "lightly", when typically also "unnecessary" targets, such as leaves of trees and plants extending into the detection area of the sensor produce a detection signal. A disadvantage in the befo- re mentioned approaching sensor use is furthermore that usually co-functioning of multiple, typically at least four, sensors is to be used, which produces a lot of delay requiring complex calculation from the data processing and significantly efficient processing power.

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The purpose of the method and guidance system for use of robot according to the present invention is to provide a decisive improvement in terms of the above described problems and thus to substantially upgrade prior art of the field. Iri order to fulfill this purpose, the method and the guidance system according to the invention are principally characterized by what is presented in the characterizing parts of the independent claims related thereto.

The most important benefits gained by the method and guidance system according to the invention notably include the simplicity and efficiency of the technic suitable for carrying out the same and for use thereof especially thanks to the guidance system enabling monitoring from a sufficiently far distance outdoors or in open indoors, which may at simplest be carried out with three parallel sounding sensors at the front of the robot, of which the sounding sensor in the middle, such as a laser scanner or a narrow beam long range ultrasonic sensor, has a significantly longer detection area than of the sounding sensors at the sides. Thanks to advantageously utilized narrow beam (typically 8-10 degrees long range ultrasonic sensors, being applied in the invention it is possible to utilize a sufficiently high transmission power in adjusting the monitoring distance of the robot by benefitting a sufficiently long detection distance. Especially the sufficiently narrow beam detection area of a long range ultrasonic sensor eliminates distractions efficiently from the robot's sides, which for its part furthers reliable determination of a long distance detection. The so called built-in filtering technique of the traditional narrow beam long range ultrasonic sensors on the market in itself eliminates non relevant targets of distraction in the determination of distance. Furthermore, with the co-function of e.g. three, or in specific circumstances even two, ultrasonic sensors, it is possible to get short responses with quite simple processing tech ^¬ nique, which eliminates the risk of the target "getting lost" also keeping in mind that the target, such as the robot's user, may need to move at a relatively high speed in open (distractionless surroundings. Other advantageous embodiments of the method and guidance system according to the invention are presented in the dependent claims related thereto.

The invention will be discussed in detail in the subsequent specification with reference to the accompanying drawings, in which: gure 1

is shown as an overhead view a basic principle of a robot carried out according to the invention, in figure 2

is shown a following function of a robot carried out according to the invention, and in figure 3a-3c

is shown as an overhead view a body of a ro- bot suitable for use according to the invention, a side view of a robot equipped with a certain utilization equipment and a side view of a robot equipped with an auxiliary power operated actuator, in figure 4

is shown a graph of a detection beam of one narrow beam long range ultrasonic sensor on the market, and in figure 5

is shown as an overhead view■ furthermore an embodiment complementing the method and guidance system according to the invention.

The invention relates first of all to a method for use of robot, which method is meant for use of a robot that is able to move by auxiliary power, such as by electri- cally, pressure medium, combustion engine and/or the like operated organs, in a self powered and preferably wirelessly controlled/controllable manner, wherein the robot has movement means 1, such as wheels la, lb, rolls, tracks and/or the like, for enabling movement of the robot on the ground in a desired direction, coupling and operating means 2 for carrying out desired functions of the robot by auxiliary powered, such as by electrically, pressure medium, combustion engine and/or the like operated actuators M and operating equipment V to be coupled therewith, a data processing unit 3, such as one or more microprocessors, programmable logics and/or the like, provided with a user interface, for controlling the robot's functions by a user, and a guidance system 4, being in connection with the data processing unit, by means of which passage of the robot is being guided by analyzing its surroundings on sonar technology, such as by one or more ultrasonic sensors, laser scanners and/or the like. In the controlling of independent passage of the robot by means of the data processing unit 3 through the guidance system 4 in order to follow passage of a target K, such as the robot's user, moving particularly in external circumstances or spacious interiors, at least three parallel sounding sensors 4al, 4a2, 4a3 are being used on the front side of the robot by co-operation of detection areas T thereof, whereby a detection area of a sounding sensor 4a3 in the middle is essentially longer than the detection area of the sounding sensors 4al, 4a2 existing at the edges.

As an advantageous embodiment of the method according to the invention, a desired distance e of the robot from the target K to be followed is being maintained by the data processing unit 3 on grounds of distance information being determined by one or more sounding sensors 4al, 4a2 , 4a3 by adjusting speed of the robot by means of regulating means, such as by one or more PID-regulators or the like, such as by accelerating/braking the movement means 1 as needed. Naturally reversing the robot is also possible if needed. In case only one sounding sensor at the edge, such as a narrow beam long range ultrasonic sensor 4al/4a2, detects the target K, the movement means 1 are, as an advantageous embodiment, being used in an accelerated manner in a rough alteration of direction of the robot towards the target K.

As a furthermore advantageous embodiment of the method according to the invention, the robot's movement direction is being altered by means of the data processing unit 3 by controlling operation of the movement means 1, such as by changing the rotation speed and/or direction with respect to each other of the wheels la, rolls, tracks and/or the like on opposite sides of the robot, wherein in case two sounding sensors 4al, 4a2 , 4a3 next to each other detect the target K at distances differing from each other, a fine adjustment is being used in the controlling of the movement means 1 in correcting the robot's direction towards the target K.

By the movement guiding described as an example above, is practically meant especially the typical guiding principle of guiding a crawler track driven vehicle, in which the change of direction of the vehicle is carried out by using the tracks on opposite sides in speeds differing from one another. Therefore on the front of the robot, shown as an advantageous embodiment in figures 2, 3b and 3c, front wheels la on opposite sides are driving ones and the middle wheel lb on the back is most profitably e.g. a so called "nose wheel". An essentially in place turning motion of the robot it is furthermore found advantageous to turn the wheel functioning as a turning center to the opposite direction in relation to the rotation direction of the wheel being rotated turning oh the other side in a fastened speed. In addition or instead of the above, it is naturally also possible to carry out the guidance of the robot by using turning pairs of wheels on the front and back of the robot .

As an advantageous embodiment of the method, in case the target K is out of the detection area T of ^" the robot's guidance system 4, the target is being tried to be detected by means of the data processing unit by using one or more sounding sensors 4a3, such as laser scanners, narrow beam long range ultrasonic sensors and/or the like, having a longer detection area than the rest of the sensors, and/or by controlling the robot to explore its surroundings by so called panora- mascanning by rotating it in place.

Furthermore as an advantageous embodiment of the method according to the invention, in detecting the target or a hinder essentially at close range at the side and/or back of the robot, three or more, most profitably wide beam short range ultrasonic sensors 4a4, such as proximity sensors or the like, are being used in sounding sidewards and/or backwards from the robot. In addition or instead of the short distance sounding sensors described above, it is naturally also possible to utilize bumpers equipped with detectors in the robot in order to guide or stop the motion of the robot e.g. as it hits obstacles by utilizing guiding logic used in e.g. robot hoovers .

The graph shown in figure 4 depicts the detection beam of a Sick / UM30 -series narrow beam long range ultrasonic sensor on the market, in which graph the letter A shows a restricted maximum detection distance, when the true maximum detection distance of such a sensor is 8000 mm, the letter B shows the detection distance on a white paper, the letter C the used maximum detection distance, and the letter D a beam of a sensor arranged on a restricting tube. Therefore, e.g. an ultrasonic sensor of this type may be utilized in production of both a normal long range detection area and furthermore a significantly longer detection area e.g. instead of a laser scanner shown in figure 5. The most advantageous way to filter the sensor's measurement signals in the robot use according to the invention is to, after the pulse has been sent, wait for the fastest echo, the volume of which exceeds a pre set limit. The built-in filtering in the sensors typically works in a way that too long or short echoes are filtered and an average is taken from the rest in order to determine distance with triangular calculation.

The invention relates on the other hand also to a guidance system for use of robot, the robot being able to move by auxiliary power, such as by electrically, pressure medium, combustion engine and/or the like operated organs, in a self powered and preferably wirelessly controlled/controllable manner, which robot has: movement means 1, such as wheels la, lb, rolls, tracks and/or the like, for enabling movement of the robot on the ground in a desired direction; coupling and operating means 2 for carrying out desired functions of the robot by auxiliary powered, such as by electrically, pressure medium, combustion engine and/or the like operated actuators M and operating equipment V to be coupled therewith; a data processing unit 3, such as one or more microprocessors, programmable logics and/or the like, provided with a user interface, for control ^¬ ling the robot's functions, by a user; and the guidance system 4, being in connection with the data processing unit, for guiding passage of the robot by analyzing its surroundings on sonar technology, such as by one or more ultrasonic sensors, laser scanners and/or the like. The guidance system comprises at least three parallel sounding sensors 4al, 4a2, 4a3 on the front side of the robot, wherein a detection area of a sounding sensor 4a3, such as a laser scanner, narrow beam long range ultrasonic sensor or the like, in the middle is essentially longer than the detection area of the sounding sensors 4al, 4a2 existing at the edges, in order to follow passage of a target K, such as the robot's user, moving particularly in external circumstances or spacious .interiors, by co-operation of the detection areas T of the parallel sounding sensors 4al, 4a2, 4a3.

As an advantageous embodiment of the guidance system according to the invention, the guidance system comprises regulating means 4b, such as one or more PID- controllers or the like, that are in connection with the data processing unit 3, in order to keep the robot at a desired distance from the target that is being followed, based on distance information determined by one or more sounding sensors.

As a furthermore advantageous embodiment of the guidance system according to the invention, in order to detect the target or a hinder essentially at close range at the side and/or back of the robot, there are three or more, most profitably wide beam short range ultrasonic sensors 4a4, such as proximity sensors or the like, sounding sidewards and/or backwards from the robot .

In figure 3a is shown as an overhead view a robot equipped with coupling means 2 and the same robot viewed from the side equipped with a tipper body V in figure 3b and in figure 3c equipped with e.g. an electrical hoover or a combustion engine driven lawn mower M . It is clear that the invention is not limited to the embodiments shown or described above, but instead, on the grounds of the basic principles of the invention, it may be varied in various ways depending on utilization purposes and circumstances at any given time. Therefore, e.g. in especially dusty circumstances it is possible to equip the robot with e.g. suitable liquid rinsing or wiper operated cleaning organs in order to keep the cells of the ultrasonic sensors clean. In addition, in the use and guidance of the robot's functions, it is possible to utilize a remote control that is connected to the robot in a wired or a wireless manner, such as by radio frequency, light operated manner or the like, in which connection as an especially advantageous alternative also short range BlueTooth-, RFID-, NFC-techiques and the like may be used. Naturally in the use of the robot, it is also possible to use broadband technic e.g. in guiding the robot's lawn mowing operation in real time with a computer or a mobile phone.