JP2010162635A - Method for correcting position and attitude of self-advancing robot - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely correct position and attitude of a robot arm by coping with an error due to sliding accompanying traveling, in a self-advancing robot mounted with the robot arm. <P>SOLUTION: This self-advancing robot 1 includes a traveling part 2 capable of self-advancing and the robot arm part 3 mounted on the traveling part 2. By photographing a detection mark 14 on a traveling road surface 5 by a camera 13 at a traveling error measuring position 7 on a traveling route, errors from set position and attitude of the traveling part 2 are detected, and the errors are corrected by an operation of the traveling part 2. By photographing a work object 8 by a camera 20, errors from set position and attitude of the robot arm part 3 are detected, and the errors are corrected by an operation of the robot arm part 3. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a self-propelled robot, and more particularly, to a method for correcting the position and orientation of a self-propelled robot that is equipped with a robot arm and performs repeated work while traveling in a predetermined place.

  A self-propelled robot equipped with a robot arm on a self-propelled section that can run freely on the road surface is more flexible in changing the layout of the production system than a robot moving on a rail placed on the road surface or ceiling Is excellent. For this reason, the self-propelled robot is suitable for operations such as loading / unloading of parts, and other than that, it is expected to be applied to various operations involving the conveyance of parts at production sites.

  On the other hand, in a self-propelled robot, although the degree varies depending on the structure of the traveling mechanism, the robot slips with respect to the traveling road surface, and the actual moving position is likely to be shifted from the theoretical moving position. For this reason, various methods have been proposed as a technique for dealing with such a deviation.

  In Patent Document 1, a mark recorded at a predetermined location is detected by image detection means attached to a robot arm, and the actual position of the robot is corrected from the deviation between the mark position detected during actual work and the mark position detected during teaching. A position correction method has been proposed. In the technique of this document, the operation point of the robot arm is controlled to be an accurate position by controlling the operation of the robot arm based on the corrected actual position.

  Further, in Patent Document 2, a calibration mark provided at a predetermined position is photographed, and the robot arm is moved so that the calibration mark falls within a predetermined deviation amount range with respect to a predetermined position, a predetermined shape, and a predetermined size in the captured image. Coarse positioning. Then, a more accurate position and orientation calibration amount is obtained from a predetermined position, a predetermined shape, and a deviation amount from the predetermined size of the calibration mark detected from the captured image captured again. The teaching data of the robot arm is calibrated three-dimensionally by this calibration amount.

  Also in Patent Document 3, a mark provided at a predetermined position is photographed by image input means attached to a robot arm. When the mark does not completely enter the captured image due to the position / orientation of the self-propelled robot, the robot arm is moved so that the entire mark falls within the captured image. Then, the position of the robot arm is corrected by comparing the image of the mark photographed in this state with the photographed image of the correction mark at the time of teaching.

  In addition, as a method of dealing with the deviation caused by the traveling of the self-propelled robot, a method of setting a guideline on the traveling road surface and driving the self-propelled robot so as to follow this guideline by a magnetic method or an optical method is devised. Has been. In addition, the current position is detected by a GPS device that is effective in the traveling area and the vehicle is traveling while correcting the position and posture, and the distance from the side wall of the building near the traveling area is detected to maintain a constant distance. A method for controlling the running is devised.

Japanese Patent No. 2680298 Japanese Patent No. 3466340 Japanese Patent No. 2743613

  In the methods disclosed in Patent Documents 1 and 2, there is no problem if the position / posture error of the entire self-propelled robot is small, but if the error is large, the mark is out of the shooting range and correction is difficult. It is possible to become. In the method disclosed in Patent Document 3, it is possible to cope with a case where a part of the mark is out of the shooting range. However, the mark needs to be within the shooting range to some extent. It is thought that it becomes. Further, in the methods disclosed in Patent Documents 1 to 3, since the position / posture error of the entire self-propelled robot calculated from the imaging result of the mark at a predetermined location is corrected only by the operation of the robot arm unit, the correction is performed. The range of possible errors is limited to the operable range of the robot arm unit.

  Regarding errors in the position and posture of the entire self-propelled robot, it is conceivable that deviations are accumulated and errors are increased particularly when the traveling operation is repeated. Therefore, particularly in applications that require a large number of repeated travels, a further improved coping method is desired for deviations caused by slips and the like associated with travel of a self-propelled robot.

  Further, in a method of running a self-propelled robot by following a guideline installed on a traveling road surface by a magnetic technique or an optical technique, it is necessary to install a guideline along the traveling route of the self-propelled robot. Therefore, it takes time to install the guideline, and it is difficult to flexibly cope with the change in the travel route of the self-propelled robot accompanying the change in the layout of the production system.

  In addition, in the method using a GPS device that is effective in the traveling area, the position and orientation detection accuracy is not so high. Also, the equipment cost tends to be expensive.

  In addition, in the method of controlling travel by detecting the distance to the side wall near the travel region, for example, when an obstacle is placed between the target side wall and the self-propelled robot, detection of the side wall is hindered. Control becomes difficult. For this reason, there is a difficulty that the layout of the production system cannot be easily changed around the traveling area of the self-propelled robot.

  Therefore, in view of the above, the present invention provides a self-propelled robot capable of correcting the position and orientation of the robot arm reliably in a self-propelled robot equipped with a robot arm by dealing with errors due to slipping and the like accompanying traveling. It is an object of the present invention to provide a method for correcting the position and orientation of the camera.

  In order to achieve the above-described object, the position and orientation correction method for a self-propelled robot according to the present invention is a position of a self-propelled robot having a self-propelled traveling unit and a robot arm unit mounted on the traveling unit. And a correction method for the posture, wherein an error from a set position and posture of the travel unit is detected as a first error at a predetermined position on the travel route, and the travel unit is corrected so as to correct the first error. And the error from the set position and posture of the robot arm unit as a second error at a predetermined work position on the travel route where the robot arm unit performs the work on the work target. And a step of controlling the operation of the robot arm unit so as to correct the second error.

  As described above, according to the present invention, the error and the position of the traveling unit that are likely to cause an error due to slip are corrected not only by the operation of the robot arm unit but also by the operation of the traveling unit itself. As a result, it becomes possible to prevent the correction from becoming difficult as in the case where the correction is performed by the operation of only the robot arm unit, and to perform appropriate operation control.

  At this time, unlike the operation guidance over the entire travel route, the error is detected at one or several predetermined positions, so it is easy to cope with the layout change of the production system. Fewer components are required.

  In addition, by correcting the position and orientation errors of the robot arm unit at the work position, it is guaranteed that highly accurate work is performed. In particular, even if the error detected at a predetermined position on the travel route is corrected as described above, even when traveling from that position to the work position, in principle, an error occurs in the travel position and posture. The error can also be compensated by correcting the error of the robot arm unit at the work position. At this time, in the present invention, since the error of the travel position and posture is corrected by the operation of the travel unit, the position of the robot arm unit is suppressed from being largely shifted due to the error of the travel position and posture. It is ensured that errors in the position and orientation of the robot arm can be detected appropriately and correction can be performed appropriately.

  In the present invention, the first error can be detected by detecting a predetermined object located around the travel route by the first detection device mounted on the self-propelled robot. Alternatively, the first error may be detected by detecting a predetermined object on the self-propelled robot with a first detection device arranged around the travel route.

  If the first detection device is mounted on a self-propelled robot, error detection can be performed with a single detection device even when error detection needs to be performed at a plurality of locations relatively far apart from each other. . On the other hand, if the first detection device is arranged around the travel route, one detection device can be shared to detect errors of a plurality of self-propelled robots.

  When the first detection device is arranged around the travel route, it is preferable to transmit detection information from the first detection device to the self-propelled robot by wireless communication. As a result, the self-propelled robot can immediately recognize an error in the position and orientation of its own self-propelled portion, and can perform quick and appropriate correction.

  Specifically, as the first detection device, it is preferable to use an imaging device and detect the position and orientation by image recognition. If image recognition is used, position and orientation can be detected relatively easily and quickly.

  In the present invention, it is preferable to detect the second error by detecting a work object with a second detection device mounted on the self-propelled robot. As described above, by detecting the error at the work position by the detection device mounted on the self-propelled robot, the error can be detected at an arbitrary work position. Therefore, even when working at a plurality of work positions, an error can be detected by a single detection device, and it is easy to cope with a layout change of the production system. An imaging device can also be suitably used for the second detection device.

  In the present invention, a common detection device can be used for detection of the first error and detection of the second error. Thereby, the number of necessary detection devices can be reduced and the cost can be reduced.

  The error of the position and orientation of the traveling unit is corrected by the robot arm unit performing an operation on the work target from a predetermined position on the traveling route for detecting an error from the set position and orientation of the traveling unit. When traveling to a predetermined work position on the travel route, the travel distance can be changed by the detected error in the position and orientation of the travel unit. This eliminates the need for a separate operation for correction, thereby improving work efficiency.

  In the present invention, in particular, the self-propelled robot is repeatedly operated so as to repeatedly pass through a predetermined position on the travel path for detecting the first error, and the traveling unit is set every time the predetermined position is passed. It is preferable to perform an operation of detecting an error from the determined position and orientation and correcting the error. Accordingly, an error due to slipping or the like accompanying traveling can be corrected every time the repeated operation is performed, and accumulation of errors due to the repeated operation can be suppressed.

  According to the present invention, in a self-propelled robot equipped with a robot arm, it is possible to cope with errors due to slipping and the like associated with traveling, correct the position and posture of the robot arm, and perform appropriate motion control. it can.

It is a perspective view which shows the production system using the self-propelled robot which concerns on one Embodiment of this invention. It is a figure which shows an example of the detection mark for detecting the running position and attitude | position of a self-propelled robot by image recognition. It is a top view which shows the running pattern of an example of the self-propelled robot of FIG. FIG. 4 is a plan view illustrating a shift in travel position and posture that occurs at a stop position 30 in FIG. 3. It is a perspective view which shows the production system of the modification of FIG. 1 by which the camera was mounted in the robot arm part in order to correct | amend operation | movement of a robot arm. It is a perspective view which shows the production system of the other modification of FIG. It is a perspective view which shows the production system of the further another modification of FIG. 1 which installed the camera for detecting the driving | running | working position and attitude | position of a self-propelled robot in the periphery of the driving | running | working area | region. It is a perspective view which shows the production system of the further another modification of FIG. 1 which detects the traveling position and attitude | position of several self-propelled robots with the camera installed in the periphery of the driving | running | working area | region. It is a perspective view which shows the production system of the further another modified example of FIG. 1 which used the distance sensor as a detection apparatus for detecting the running position and attitude | position of a self-propelled robot.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a production system using a self-propelled robot 1 according to an embodiment. In FIG. 1, for the sake of convenience, the self-propelled robot 1 is illustrated at two different positions for the sake of convenience, but here, one self-propelled robot 1 is used. Assumed production system.

  The self-propelled robot 1 has a traveling unit 2 and a robot arm unit 3. The traveling unit 2 is a mechanism unit for causing the entire self-propelled robot 1 to travel on the traveling road surface 5. Various configurations of the traveling unit 2 have been devised so far, but from the viewpoint of cost and controllability, a configuration in which a tire or a wheel is disposed in contact with the traveling road surface 5 and driven by a driving source such as a motor. Is the most commonly used. Such a configuration can also be adopted for the traveling unit 2 in the present embodiment, but is not limited thereto.

  The robot arm unit 3 is attached on the traveling unit 2. In the figure, the robot arm unit 3 in the form of a vertical articulated robot is shown. However, the robot arm unit 3 may be any mechanism that can perform a desired work by automatic control according to a program. It may be in the form of an articulated robot or a parallel link robot. A plurality of robot arm units 3 may be attached on the traveling unit 2.

  A hand 4 can be attached to the tip of the robot arm unit 3. As the hand 4, one having a configuration according to the application can be used. For example, the hand 4 can have various sizes and shapes capable of holding the hand 4 according to the parts to be loaded / unloaded. Moreover, the hand 4 incorporating a mechanism for processing such as automatic assembly of products and welding / painting can also be used, whereby the self-propelled robot 1 can be applied to a wide range of uses.

  In addition, a control device and a drive battery (not shown) for controlling both the traveling unit 2 and the robot arm unit 3 are mounted inside the traveling unit 2 of the self-propelled robot 1. The self-propelled robot 1 is configured such that a cable for supplying electricity is not normally connected by mounting a driving battery, but may be configured to operate with the cable connected. Moreover, it is good also as a structure which has arrange | positioned the control apparatus outside the self-propelled robot 1 and was connected to the self-propelled robot 1 by electrical connection means, such as a cable.

  Such a self-propelled robot 1 is suitable for use in, for example, loading / unloading parts, that is, transporting parts between predetermined places apart from each other, for example, between a stacking unit and a working unit. Can be used to As another application, it is conceivable to perform processing by moving the robot arm unit 3 including the hand 4 that performs operations such as welding and painting to various places. As a result, it is possible to reduce the number of robots introduced and improve the operation rate per unit, and to construct a production system with high productivity at a low cost compared to placing robots at each place where work is required. it can.

  Here, the self-propelled robot 1 is not configured to move on a fixed rail, but is configured to freely travel on the traveling road surface 5 in the production site by the traveling unit 2. For this reason, the self-propelled robot 1 also changes the operation procedure even when the layout of the production system such as the manufacturing process and the arrangement of necessary processing devices is changed in accordance with the change in the configuration and specifications of the product. It can be used continuously. Therefore, the configuration of the self-propelled robot 1 is a very efficient robot configuration in a production site for high-mix low-volume production that requires relatively frequent changes in the layout of the production system in accordance with changes in production products. It can be said that it is one.

  Next, the operation will be described. Generally, the self-propelled robot 1 moves to the work position 6 by the traveling unit 2 and performs a predetermined work on the work target 8 by the robot arm 3. As the operation by the robot arm 3, various operations such as loading / unloading of parts, welding / painting can be set. Such an operation of the robot arm 3 can be executed in a known manner and is not directly related to the present invention, and thus detailed description thereof is omitted.

  In the present embodiment, the self-propelled robot 1 is moved to the travel error measurement position 7 in addition to the work position 6. A detection mark 14 is provided on the traveling road surface 5 at the traveling error measurement position 7. A camera 13 for photographing the detection mark 14 is attached to one side surface of the traveling unit 2 of the self-propelled robot 1. The camera 13 is attached downward so that the detection mark 14 on the traveling road surface 5 can be properly photographed.

  FIG. 2 shows an example of the detection mark 14. As in this example, the detection mark 14 preferably has a shape in which one predetermined direction is different from the other direction, and thus can be distinguished. Accordingly, by photographing the detection mark 14 and processing the image, it is possible to determine not only the position of the camera 13 with respect to the detection mark 14 but also the posture (direction in a plane parallel to the traveling road surface 5). In order to detect the posture, a configuration may be adopted in which marks provided at a plurality of locations may be detected, but the detection speed can be increased by enabling the posture to be determined by the detection mark 14 at a single location.

  Actually, the self-propelled robot 1 normally moves to a plurality of work positions 6 and takes advantage of the advantage of having the traveling unit 2. FIG. 3 shows an example of such a travel pattern. That is, in the example shown in the figure, the self-propelled robot 1 sequentially moves from the stop position 30 corresponding to the travel error measurement position 7 to the stop positions 31 and 32 corresponding to the two work positions 6, and reaches the stop position 30. It operates repeatedly with a pattern of returning.

  Here, the traveling position and posture of the traveling unit 2 can be expressed according to the reference coordinate system 10 set on the traveling road surface 5. That is, the position x, y of the reference point such as the center in the horizontal plane of the self-propelled robot 1 according to the reference coordinate system 10 and the reference plane of the self-propelled robot 1, for example, one side surface of the traveling unit 2. The reference coordinate system 10 can be expressed by, for example, an angle θ with respect to the x axis. In FIG. 3, a description such as (x30, y30, θ30) represents each stop position 30, 31, 32 using such a reference coordinate system 10.

  Such an expression using x, y, θ is intuitively easy to understand and easy to handle. Therefore, it is preferable to use it as a specification of an operation position by an operator or a storage information format of a stop position in the control device. Of course, other representation formats can be used for actual control.

  The travel between the stop positions 30, 31, 32 by the travel unit 2 is performed by operating the wheels of the travel unit 2 in an appropriate pattern according to the information on the position and posture of each stop position 30, 31, 32. Can be executed by. However, in principle, it is inevitable that an error occurs in the actual operation position. Therefore, as shown in FIG. 4, at the stop position 30 corresponding to the travel error measurement position 7, the self-propelled robot 1 returns to the stop position 30 through the stop positions 31 and 32, and then the theoretical position and The position and orientation (x30 ′, y30 ′, θ30 ′) deviate from the orientation (x30, y30, θ30).

  In this embodiment, the self-propelled robot 1 is moved to the travel error measurement position 7 by such a shift (first error) in the travel position and posture of the self-propelled robot 1 at the travel error measurement position 7. In this state, the detection mark 14 is captured by the camera 13 and detected by recognizing the image. That is, in general, a deviation in the position and orientation of the detection mark 14 on the captured image corresponds to a deviation in the running position and posture of the self-propelled robot 1. Therefore, for example, the self-propelled robot 1 is disposed at a position where the travel error measurement position 7 is not displaced, for example, the image of the detection mark 14 photographed by the camera 13 in the state at the time of teaching, and during actual operation. By comparing with the captured image, it is possible to obtain the deviation of the running position and the posture. Alternatively, the positional relationship between the camera 13 and the detection mark 14 may be theoretically obtained based on the actual size of the detection mark 14 and the deviation of the traveling position and posture may be obtained based on the positional relationship.

  Next, when the self-propelled robot 1 is moved to the stop position 31 by the travel of the travel unit 2, the travel position and posture of the self-propelled robot 1 at the stop position 30 that is the travel error measurement position 7 are as described above. The deviation can be corrected by changing the travel amount by the amount of deviation obtained in (1). Alternatively, the correction operation may be performed independently, that is, for example, the traveling unit 2 may be operated at the stop position 30 by the calculated deviation of the traveling position and posture. However, the method of correcting the amount of movement to the stop position 31 is preferable in that an independent correction operation is unnecessary and it is possible to suppress an increase in processing time. In addition, in the case where the deviation occurs in the axial direction of the tire or wheel of the traveling unit 2, the correction operation on the spot is complicated, but the traveling amount between the stop positions 30 and 31 is changed. According to the above operation, such correction can be performed relatively easily.

  The self-propelled robot 1 also has a camera 20 attached to the robot arm unit 3. As shown in FIG. 5, an image is taken by the camera 20 at the work position 6. It is used for the operation control. That is, at the work position 6, for example, an image of the work object 8 or the like is taken by the camera 20, thereby determining the position or posture of the operation unit such as the tip of the robot arm unit 3 with respect to the work object 8. it can. Then, a deviation (second error) from the position and posture of the operation unit set by the teaching operation or the like is obtained, and by correcting the operation of the robot arm unit 3 by the deviation, the robot arm unit 3 increases the movement. Predetermined work can be performed with accuracy.

  At this time, the shift of the travel position and the posture is corrected at the stop position 30 that is the travel error measurement position 7 or while moving from the stop position 31 to the stop position 31, but during the travel from the stop position 30 to 31 or 32. However, an error due to slipping occurs. For this reason, the deviation of the position and posture of the robot arm unit 3 includes a deviation due to the deviation of the traveling position and posture of the self-propelled robot 1. In traveling by the traveling unit 2, an error is likely to occur due to slipping in particular, whereas an error is unlikely to occur in the operation of the robot arm unit 3. Therefore, in the error obtained by photographing the work object 8 by the camera 20, the error in the running position and the posture is often dominant, and the robot can obtain the error in the running position and the posture. The camera 20 may be arranged so as not to be affected by the operation of the arm unit 3, or an error calculation process may be performed.

  Further, in the present invention, the deviation of the running position and posture is corrected for each cycle of the repetitive operation, so that it does not accumulate and does not increase, but can be kept relatively small. For this reason, it is possible to suppress the deviation of the position and posture of the camera 20 from becoming larger as a predetermined shooting object such as the work object 8 is out of the shooting range of the camera 20. Therefore, a predetermined photographing object can be appropriately photographed by the camera 20, and the operation of the robot arm unit 3 can be appropriately corrected and controlled based on the photographed image.

  Here, the camera 20 used for operation control of the robot arm unit 3 may be used for purposes other than correcting the position and orientation errors of the operation unit as described above. For example, when parts are loaded / unloaded by the robot arm unit 3, the work object 8 may not be placed at a predetermined position accurately because the parts are so-called “separated”. is there. In this case, it is necessary to recognize the exact position of the work object 8 during actual operation, and for this purpose, image recognition by the camera 20 can be used. Also in this case, the error of the running position and the posture is suppressed to be small, so that the work object 8 that is “separated” can be appropriately photographed by the camera 20 and an appropriate work can be executed.

  At this time, it is conceivable that a camera capable of loading / unloading the parts to be “separated” is installed in the part loading section, but the camera 20 mounted on the self-propelled robot 1 may be used. By using, it becomes possible to work at an arbitrary place. As a result, it is possible to obtain advantages such as being able to flexibly respond to changes in the layout of the production system.

  The calculation of position and orientation errors by image recognition using the camera 20 is performed, for example, when the self-propelled robot 1 is accurately positioned at the work position 6, for example, at the time of teaching, by shooting a reference image and at the time of actual operation. This can be performed based on the difference between the processed image and the reference image. At this time, in the case of “stacking”, the difference between the photographed image at the time of operation and the photographed image at the time of teaching is shifted from that at the time of teaching because the work object 8 is “stacked”. The difference based on the above and the difference based on the positional deviation of the camera 20 are added together. When loading / unloading the work object 8 by the robot arm unit 3, the robot arm unit 3 corrects the added difference and loads the work object 8. When unloading to a predetermined location whose position is defined with respect to the system 10, the unloading location is shifted by a difference based on the shift of the position of the camera 20 with respect to the predetermined location. In this case, for example, the position of the camera 20, that is, the position and posture of the robot arm unit 3 is determined as necessary by using the position of the support base of the work object 8. 3 can be used for operation control.

  Note that the camera 20 for correcting the operation of the robot arm unit 3 may be disposed on the traveling unit 2. In addition, a common camera may be used for correcting the operation of the robot arm unit 3 and correcting the traveling position and posture by the traveling unit 2. Thereby, the number of cameras can be reduced and the cost of the production system can be reduced. When sharing the camera, the camera is preferably mounted on the robot arm unit 3. Accordingly, the posture of the robot arm unit 3 is appropriately changed to a posture suitable for photographing each of the detection mark 14 and the work object 8 and the appropriate photographing can be performed. it can.

  According to the present embodiment described above, the self-propelled robot 1 can be accurately operated by performing the correction operation by the traveling unit 2 with respect to the deviation of the traveling position and posture due to slipping or the like accompanying the traveling of the self-propelled robot 1. It can be operated. The self-propelled robot 1 that can freely travel on the traveling road surface 5 has a high degree of freedom in traveling and no restriction is imposed on traveling. Therefore, it traveled at a particularly high speed by slipping on the traveling road surface 5. In this case, an error is likely to occur in the traveling position and posture. Therefore, by correcting the deviation of the travel position and posture, it is possible to greatly contribute to the improvement of the operation accuracy. In addition, since it is possible to correct the deviation of the running position and posture for each cycle during the repetitive operation, it is possible to avoid the deviation from being accumulated due to accumulation of deviations in a plurality of cycles.

  In the present embodiment, the travel error is measured only at the travel error measurement position 7. Accordingly, it is possible to flexibly cope with a change in the layout of the production system, as compared with the case where the operation is guided over the entire travel route by providing a guideline or measuring the distance from the side wall near the travel region. That is, if it is a part other than the vicinity of the detection mark 14, the layout can be changed without changing the configuration relating to the correction of the running error. For this reason, even if the layout of the production system is changed, it is difficult to correct an error or to change the configuration for correction. Therefore, when the layout is changed, the configuration relating to the correction of the running error can be made with the minimum necessary change, and can be dealt with at low cost and in a short time. Further, as compared with the case where the guideline is provided over the entire travel route, it is only necessary to provide the detection mark 14 at a predetermined location, so that the configuration is simple and the cost can be reduced.

  The above-described embodiments are examples of the present invention, and various modifications can be made within the scope of the present invention defined in the claims. For example, the present invention can be applied to a case where a plurality of self-propelled robots 1 are run in the same region.

  The camera 13 is preferably attached to the traveling unit 2 so as not to be affected by the operation of the robot arm unit 3 in order to detect the traveling position and posture, but may be configured to be attached to the robot arm unit 3. .

  Further, the travel error measurement position 7 is not a position different from the work position 6, but one of the plurality of work positions 6 is set as the travel error measurement position 7, that is, the detection mark 14 is arranged at the work position 6. The traveling position of the traveling robot 1 may be detected by the photographing. In addition, there may be three or more work positions 6, especially when there are a large number of work positions 6, a plurality of travel error measurement positions 7 are set as a whole, one for each of several work positions 6. Also good. How much the travel error measurement position 7 is set depends on the friction coefficient between the tires or wheels of the travel unit 2, the shape and material of the travel unit 2 and the road surface condition of the travel road surface 5, and the travel of the self-propelled robot 1. In consideration of speed and the like, it may be set as appropriate so that the error in the travel position and posture does not become too large. In addition, when the error of the traveling position and posture generated in one cycle of the repetitive operation is sufficiently small, the correction operation may be performed once every several cycles.

  Further, if the detection mark 14 is arranged on the traveling road surface 5 as in the above-described embodiment, for example, even when a plurality of self-propelled robots are arranged in the production system, the field of view is given to other self-propelled robots. The detection mark 14 can be photographed by the camera 13 without being blocked, which is preferable. Furthermore, even if the position and posture of the self-propelled robot 1 are deviated, the field of view of the camera 13 is prevented from being obstructed by its own traveling unit 2, the robot arm unit 3, and other obstacles around the traveling region. can do. However, when it is difficult to place the detection mark 14 on the traveling road surface 5, as shown in FIG. 6, the side surface of a structure such as a machine tool or a building around the traveling region of the self-propelled robot 1 is used. For example, the detection mark 14 may be arranged.

  Further, as shown in FIG. 7, the camera 11 may be arranged around the traveling area of the self-propelled robot 1 and the detection mark 24 provided on the self-propelled robot 1 may be photographed. In this case, it is necessary to transmit the information acquired by the camera 11 to the self-propelled robot 1, but in particular by using wireless communication, the information is transmitted to the self-propelled robot 1 without losing the immediacy of the information. Can do. It is also conceivable to use a camera arranged around the traveling area of the self-propelled robot 1 for detecting the position and posture of the operation unit such as the tip of the robot arm 3.

  Further, when the camera 11 is arranged around the traveling area of the self-propelled robot 1, the camera 11 may be shared with a plurality of self-propelled robots 1 as shown in FIG. 8. As a result, the number of cameras can be reduced rather than providing the cameras 13 in each of the self-propelled robots 1, and the equipment cost as a whole may be reduced.

  On the other hand, when the traveling area of the self-propelled robot 1 is wide, or when a large number of self-propelled robots 1 are used, so that the self-propelled robot 1 can be reliably detected at any position. You may arrange | position the camera 11 in the several places around a driving | running | working area | region. In the configuration in which the camera 13 is provided in the self-propelled robot 1, it is not necessary to increase the number of cameras even if the traveling range is wide, and it is only necessary to increase the detection marks 14 on the traveling road surface 5. For this reason, when the number of the self-propelled robots 1 is small and the travel range is wide, it is advantageous to provide a camera for the self-propelled robot 1 in terms of the cost and construction time of the entire production system. In some cases. Therefore, whether the camera is provided in the self-propelled robot 1 or in the vicinity of the traveling area of the self-propelled robot 1 can be appropriately selected according to the configuration of the production system.

  In order to detect the position of the self-propelled robot 1 using the cameras 13 and 11, a specific object that can be identified from an image or the like is used instead of providing the special detection marks 14 and 24. Also good. That is, for example, the camera 13, 11 is used to photograph the road surface 5, the structure around the running area, the characteristic structure of the self-propelled robot 1, or the characteristic paint part that originally exists. The position may be determined.

  In addition, a method for detecting the position and orientation by image recognition using an imaging device such as the cameras 13, 11, and 20 is relatively easy as today's technology, and quickly including not only the position but also the orientation. Although it is possible to perform detection and is one of excellent methods, other detection devices may be used. As such an example, FIG. 9 shows a configuration using a distance sensor.

  When using a distance sensor as a detection device for detecting the position and orientation, it is necessary to mount at least two or more distance sensors on the traveling unit 2. Moreover, the position and posture of the self-propelled robot 1 can be detected with high accuracy by arranging a plurality of objects to be detected by the distance sensor.

  That is, FIG. 9 shows an example in which two distance sensors 11 a and 11 b are provided on one side surface of the traveling unit 2. The two distance sensors 11a and 11b detect the distances to the detected bodies 12a and 12b arranged in the structures around the traveling area. Then, the positions (xa, ya) and (xb, yb) of the distance sensors 11a and 11b can be calculated from the distances between the distance sensors 11a and 11b and the detected bodies 12a and 12b. The position and orientation of the self-propelled robot 1 can be calculated from these positions.

DESCRIPTION OF SYMBOLS 1 Self-propelled robot 2 Traveling part 3 Robot arm part 13,20 Camera 14 Detection mark

Claims (10)

A method for correcting the position and orientation of a self-propelled robot having a self-propelled traveling unit and a robot arm unit mounted on the traveling unit,
Detecting an error from a set position and orientation of the traveling unit as a first error at a predetermined position on the traveling route, and controlling the operation of the traveling unit so as to correct the first error. When,
An error from a set position and posture of the robot arm unit is detected as a second error at a predetermined work position on the travel route where the robot arm unit performs a work on a work target, and the second error is detected. Controlling the operation of the robot arm so as to correct the error of 2;
A method for correcting the position and orientation of a self-propelled robot.   2. The self-propelled robot according to claim 1, wherein the first error is detected by detecting a predetermined object located around a travel route by a first detection device mounted on the self-propelled robot. To correct the position and orientation of the camera.   2. The self-propelled robot according to claim 1, wherein the first error is detected by detecting a predetermined object on the self-propelled robot by a first detection device arranged around a travel route. Position and orientation correction method.   The method for correcting the position and orientation of a self-propelled robot according to claim 3, wherein information detected by the first detection device is transmitted to the self-propelled robot by wireless communication.   The method for correcting the position and orientation of a self-propelled robot according to any one of claims 2 to 4, wherein the first detection device is an imaging device and detects the position and orientation by image recognition.   The self-propelled type according to any one of claims 1 to 5, wherein the second error is detected by detecting the work object by a second detection device mounted on the self-propelled robot. A method for correcting the position and orientation of a robot.   The method for correcting the position and orientation of a self-propelled robot according to claim 6, wherein the second detection device is an imaging device and detects the position and orientation by image recognition.   The method for correcting the position and orientation of a self-propelled robot according to claim 1, wherein a common detection device is used for detecting the first error and detecting the second error.   When traveling from the predetermined position on the travel route on which the first error is detected to the work position, the first travel amount is changed by changing the travel amount by the detected first error. The method for correcting the position and orientation of a self-propelled robot according to claim 1, wherein the error is corrected.   The self-propelled robot is repeatedly operated so as to repeatedly pass through the predetermined position on the travel route where the first error is detected, and the first error is detected each time the predetermined position is passed. The method for correcting the position and orientation of a self-propelled robot according to any one of claims 1 to 9, wherein an operation for correcting the first error is performed.

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