Work robot system

Abstract

The present application provides a kind of working robot system, can effectively realize the breakage prevention of robot, handling device, article etc., the system has: handling device, which carries article along predetermined path;Robot, the object part of article carried by handling device is carried out predetermined work;Control unit, which controls robot;First sensor, which is visual sensor installed at the front end of robot;Second sensor, which is configured at the position along the path;And force detection unit, which detects the force generated due to the contact between the component or tool supported by the robot and the article, the control unit is used to obtain the position of at least the object part according to the output of the second sensor, control the component or tool supported by the robot to approach the object part according to the obtained position, when the robot performs predetermined work, while performing the following control of at least the front end of the robot following the object part, force sensation control is performed based on the detection value of the force detection unit.

Description

[0001] This application is a divisional application of the Chinese invention patent with an application date of February 2, 2019, a priority date of February 8, 2018, application number "201910106489.3", and an invention title of "Operating Robot System". Technical Field

[0002] This invention relates to a work robot system. Background Technology

[0003] In the past, the handling equipment was frequently stopped when assembling components onto items being transported by a conveying device. This was especially true when precisely assembling components onto large items such as car bodies, where the transport of items by the conveying device needed to be stopped. This sometimes led to a decrease in work efficiency.

[0004] On the other hand, a production line is known, comprising: a robot; a transport device for transporting items; a slide rail arranged along the transport device; and a moving device for moving the robot along the slide rail (for example, see Patent Document 1). In this production line, while the transport device is used to transport items, the robot performs defect inspection and polishing of the items. Furthermore, during defect inspection and polishing, the moving device causes the robot to move along the slide rail at the same speed as the transport device's speed for transporting the items.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 08-72764 Summary of the Invention

[0008] The problem the invention aims to solve

[0009] In the production line, only defect inspection and polishing are performed. On the other hand, when operations are performed where robots and items may interfere with each other, force control of the robot is required to prevent damage to the robot, handling device, items, etc. However, since items being moved by the handling device may make unpredictable movements, it is difficult to achieve the above-mentioned damage prevention without making the control cycle of force control extremely short or improving the sensitivity of force control.

[0010] However, since robots can only operate within their control cycles, the control cycle for force sensing cannot be shorter than the robot's control cycle. In other words, without changing the robot's inherent performance, it remains difficult to achieve the aforementioned damage prevention. Furthermore, increasing the sensitivity of force sensing increases the likelihood of robot vibration. Additionally, in cases where objects exhibit unpredictable behavior, even force sensing control applied over several consecutive control cycles may fail to improve the contact between the robot and the object. In such cases, the likelihood of robot vibration also increases.

[0011] This invention is based on the above circumstances. One object of this invention is to provide a work robot system that can effectively prevent damage to robots, handling devices, items, etc.

[0012] Solution for solving the problem

[0013] To solve the above problems, the present invention adopts the following solution.

[0014] One aspect of the present invention provides a work robot system comprising: a handling device for handling an article; a robot for performing a predetermined operation on an object portion of the article handled by the handling device; a control unit for controlling the robot; a sensor mounted on the robot for detecting the position of the object portion of the article handled by the handling device relative to the robot; and a force detection unit for detecting the force generated by contact between a component or tool supported by the robot and the article. When the robot performs the predetermined operation, the control unit controls the robot using the detection results of the sensor and performs force-sensing control based on the detection values ​​of the force detection unit.

[0015] In the above solution, sensors mounted on the robot detect the position of the object being transported by the handling device relative to the robot, and the robot is controlled using the sensor detection results. Therefore, even without force-sensing control, the control unit can identify the positional relationship between the robot-supported component or tool and the object, and can detect whether there is contact between them. For example, even without force-sensing control, the control unit can detect abnormalities in the handling device, such as significant changes in the movement of the object being transported. Therefore, without forcibly shortening the control cycle of force-sensing control, damage to the robot, handling device, and object can be prevented, and robot vibration can be suppressed.

[0016] In the above scheme, preferably, the control unit uses the detection value of the force detection unit to perform force control while using the detection result of the sensor to make the component or tool supported by the robot follow the object.

[0017] In this way, the control unit uses the detection results of sensors to make the robot's parts or tools follow the object. Therefore, when the robot performs a predetermined task, the control unit can accurately control the position and orientation of the parts or tools supported by the robot relative to the object being transported by the handling device. This is beneficial for preventing damage to robots, handling devices, and objects without shortening the control cycle of force control or increasing the sensitivity of force control, and it also helps to suppress the occurrence of robot vibration.

[0018] In the above scheme, preferably, the working robot system includes a detection unit that detects at least the position of the object part of the item on the handling device, and the control unit, based on the detection result of the detection unit, moves the robot's component or the tool closer to the object part.

[0019] This scheme facilitates accurate control of bringing robot-supported components or tools close to the object.

[0020] In the above scheme, preferably, when the position of the object relative to the robot, as detected by the sensor, changes beyond a predetermined reference, at least one of the control unit and the handling device performs an abnormal response operation.

[0021] In this solution, as described above, after identifying the positional relationship between the robot-supported component or tool and the object, the control unit also performs anomaly response based on the sensor detection results. This configuration helps to effectively prevent damage to the robot, handling device, and objects, and also helps to suppress robot vibration.

[0022] Invention Effects

[0023] According to the present invention, damage to robots, handling devices, items, etc. can be effectively prevented. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of a work robot system according to one embodiment of the present invention.

[0025] Figure 2 This is a block diagram of the control device of the robot system in this embodiment.

[0026] Figure 3 This is an example of image data captured by the detection device of the robot system of this embodiment.

[0027] Figure 4 This is a flowchart illustrating the operation of the control unit of the robot system in this embodiment.

[0028] Figure 5 This diagram illustrates the calculation of the movement amount of the robot system in this embodiment.

[0029] Explanation of reference numerals in the attached figures

[0030] 1. Operational Robot System

[0031] 2. Handling device

[0032] 2a motor

[0033] 2b Working position detection device

[0034] 3 rollers

[0035] 10 robots

[0036] 11 servo motors

[0037] 20 control devices

[0038] 21 Control Department

[0039] 22 display devices

[0040] 23 Storage Department

[0041] 23a System Program

[0042] 23b Action Procedure

[0043] 23c Follower Control Program

[0044] 23D Force Control Program

[0045] 24 servo controllers

[0046] 25 servo controllers

[0047] 26 Input Section

[0048] 30 lots

[0049] 31 servo motors

[0050] 32 force sensors

[0051] 40 detection devices

[0052] 50 sensors

[0053] 100 items

[0054] 101 Object Department

[0055] 101a hole

[0056] 110 parts

[0057] 111 Installation Department

[0058] 111a axis Detailed Implementation

[0059] Hereinafter, an embodiment of the work robot system 1 according to the present invention will be described with reference to the accompanying drawings.

[0060] like Figure 1 As shown, the work robot system 1 of this embodiment includes: a handling device 2 for handling an article 100 that is the object of work; a robot 10 for performing a predetermined operation on the object part 101 of the article 100 handled by the handling device 2; a control device 20 for controlling the robot 10; a detection device 40 as a detection unit; and a sensor 50 mounted on the robot 10.

[0061] The detection device 40 detects that the article 100 has been moved to a predetermined position. The detection device 40 can acquire data that determines the position and orientation of the object portion 101 of the article 100 being moved by the transport device 2. Any device with this function can be used as the detection device 40. In this embodiment, the detection device 40 is a photoelectric sensor. In this case, the detection device 40 detects that the article 100 has been moved to the position where the detection device 40 is located.

[0062] Article 100 is not limited to a specific type of article; in this embodiment, for example, article 100 is the body of a car. The conveying device 2 uses a motor 2a to drive several of the multiple rollers 3 to convey article 100. In this embodiment, the conveying device 2 is oriented towards... Figure 1 The right-side transporter 100 is used. Motor 2a may be equipped with a working position detection device 2b. The working position detection device 2b sequentially detects the rotational position and amount of rotation of the output shaft of motor 2a. The working position detection device 2b is, for example, an encoder. The detection values ​​from the working position detection device 2b are sent to the control device 20.

[0063] The object portion 101 is the part of the article 100 where the robot 10 performs a predetermined task. In this embodiment, as part of the predetermined task, the robot 10's hand 30 lifts the component 110, and the robot 10 mounts the mounting portion 111 of the component 110 onto the object portion 101. Thus, for example, the shaft 111a extending downward from the mounting portion 111 of the component 110 engages with the hole 101a provided on the object portion 101 of the article 100.

[0064] Furthermore, while the item 100 is being moved by the handling device 2, the robot 10 attaches the mounting part 111 of the component 110 to the object part 101.

[0065] The robot 10 is not limited to a specific type. The robot 10 in this embodiment has multiple servo motors 11 that drive multiple movable parts respectively (see reference). Figure 2 Each servo motor 11 has a working position detection device for detecting its working position; for example, the working position detection device is an encoder. The detection value of the working position detection device is sent to the control device 20.

[0066] A hand 30 is mounted on the front end of the robot 10. In this embodiment, the hand 30 is supported by a gripping member 110 with multiple claws, but a hand that utilizes a support member 110 such as magnetism or air attraction can also be used.

[0067] Hand 30 is equipped with a servo motor 31 for driving the gripper (see reference) Figure 2 The servo motor 31 has a working position detection device for detecting its working position; for example, the working position detection device is an encoder. The detection value of the working position detection device is sent to the control device 20.

[0068] Furthermore, various servo motors such as rotary motors and linear motors can be used as servo motors 11 and 31.

[0069] A force sensor 32 is mounted on the front end of the robot 10. The force sensor 32 detects, for example... Figure 3 The force sensor 32 is shown in the X-axis direction, Y-axis direction, Z-axis direction, around the X-axis, around the Y-axis, and around the Z-axis. Any sensor capable of detecting the direction and magnitude of the force applied to the hand 30 or the component 110 held by the hand 30 is acceptable. Therefore, in this embodiment, the force sensor 32 is disposed between the robot 10 and the hand 30, but the force sensor 32 may also be disposed within the hand 30.

[0070] Sensor 50 is mounted on the front end of robot 10. In one example, sensor 50, like hand 30, is mounted on the wrist flange of robot 10. Sensor 50 is a two-dimensional camera, a three-dimensional camera, a three-dimensional distance sensor, etc. In this embodiment, sensor 50 is a two-dimensional camera, and sensor 50 is used to sequentially acquire data when the object 101 enters a predetermined range of the field of view. Figure 3 The sensor 50 transmits image data of the object portion 101 shown. The sensor 50 sequentially sends the image data to the control device 20. The image data is data capable of determining the position of at least one of the two object portions 101. Furthermore, for example, the orientation of the object portion 101 can also be determined based on the positional relationship between the two object portions 101 in the image data.

[0071] The position and orientation of the coordinate system of sensor 50, and the position and orientation of the coordinate system of robot 10, have been pre-associated within the control device 20. For example, the coordinate system of sensor 50 is set as the reference coordinate system of robot 10 operating based on motion program 23b. Coordinate systems with the tool center point (TCP) of hand 30 as the origin, coordinate systems with the reference position of component 110 as the origin, etc., are represented relative to the reference coordinate system.

[0072] like Figure 2 As shown, the control device 20 includes: a control unit 21 having a CPU, RAM, etc.; a display device 22; a storage unit 23 having non-volatile memory, ROM, etc.; multiple servo controllers 24 corresponding to the servo motors 11 of the robot 10; a servo controller 25 corresponding to the servo motors 31 of the hand 30; and an input unit 26 connected to the control device 20. In one example, the input unit 26 is an input device such as an operation panel that can be carried by the operator. The input unit 26 sometimes also wirelessly communicates with the control device 20.

[0073] The storage unit 23 stores system program 23a, which performs the basic functions of control device 20. Additionally, the storage unit 23 stores operation program 23b, follow control program 23c, and force control program 23d.

[0074] Based on these programs, the control unit 21 sends control commands for performing predetermined operations on the item 100 to each servo controller 24, 25. Thus, the robot 10 and the hand 30 perform the predetermined operations on the item 100. (See reference...) Figure 4 The flowchart explains the operation of the control unit 21 at this time.

[0075] First, when the detection device 40 detects the item 100 (step S1-1), the control unit 21 sends control commands to the robot 10 and the hand 30 based on the action program 23b (step S1-2). As a result, the component 110 is held by the hand 30, and the robot 10 moves the axis 111a of the component 110 held by the hand 30 closer to the hole 101a of the object part 101. At this time, the control unit 21 can use data such as the transport speed of the transport device 2 and the position of the object part 101 within the item 100; as long as it is within the field of view of the sensor 50, the movement of the transport device 2 is not required. Furthermore, after steps S1-7 described later, based on the action program 23b, the axis 111a of the component 110 is engaged with the hole 101a of the item 100.

[0076] Through the control of robot 10 in steps S1-2, for example... Figure 1As shown, component 110 reaches the position and orientation for engagement. Therefore, when object portion 101 is present within the field of view of sensor 50 (steps S1-3), control unit 21 begins control based on follow-up control program 23c (steps S1-4). This control can be achieved, for example, by using the following two controls. Furthermore, in both of these controls, sensor 50 at least detects the position of object portion 101, and control unit 21 causes the front end of robot 10 to follow object portion 101 based on the detected position.

[0077] The first control is as follows: by always positioning the feature shapes and / or feature points on the item 100 at predetermined positions within the field of view of the sensor 50, the front end of the robot 10 follows the object 101. The second control is as follows: by detecting the actual position (relative to the position of the robot 10) of the feature shapes and / or feature points on the item 100, and correcting the motion program 23b based on the difference between the position of the feature shapes and / or feature points and the actual position, the front end of the robot 10 follows the object 101.

[0078] In the first control, the control unit 21 detects feature shapes and / or feature points on the image data sequentially acquired by the sensor 50. The feature shapes include the overall shape of the object portion 101, the shape of the hole 101a in the object portion 101, and the mark M (…) provided on the object portion 101. Figure 3 The shape, etc. Feature points are points indicating the center of gravity of the hole 101a in the object part 101, points indicating the center of gravity of the mark M provided on the object part 101, etc. When the distance between the sensor 50 and the object part 101 in the Z direction (viewing direction) changes, the size of the feature shape changes, but the change of the feature points is small or not at all.

[0079] Furthermore, the control unit 21 sends control commands to the servo controller 24 using image data sequentially obtained by the sensor 50. These control commands are used to always position the detected feature shapes and / or feature points at predetermined positions in the image data.

[0080] At this time, the control unit 21 preferably uses feature shapes and / or feature points that can be seen from the sensor 50 when fitting, rather than feature shapes and / or feature points that become invisible from the sensor 50 when fitting. Alternatively, the control unit 21 can change the feature shapes and / or feature points used for tracking control when the feature shapes and / or feature points used for tracking control become invisible from the sensor 50.

[0081] In the second control, the control unit 21 uses image data sequentially acquired by the sensor 50 to detect the actual position of the feature shapes and / or feature points on the item 100 relative to the fixed coordinate system of the robot 10. Furthermore, the control unit 21 corrects the teaching points of the action program 23b taught relative to the fixed coordinate system based on the difference between the position of the feature shapes and / or feature points and the actual position.

[0082] Furthermore, in the first control, the control unit 21 can also calculate the amount of movement of the object unit 101. In this case, the control unit 21 also uses the calculated amount of movement to make the front end of the robot 10 follow the object unit 101.

[0083] The amount of movement of the object section 101 is calculated sequentially, for example, based on image data acquired by the sensor 50. For example, the amount of movement of the object section 101 is calculated using the characteristic shapes and / or feature points appearing within the field of view of the sensor 50.

[0084] The control unit 21 performs feature point matching within a series of consecutive image data. Since the front end of the robot 10 moves in the same direction as the object 100 via motion program 23b, the positions of the feature points hardly change within the series of consecutive image data. However, when the conveying speed of the conveying device 2 is not perfectly synchronized with the moving speed of the front end of the robot 10, they move relative to each other. This relative movement is captured within the series of consecutive image data. Furthermore, the amount of movement of the object 101 is calculated sequentially using the moving speed of the front end of the robot 10 and the moving speed of the front end of the robot 10 relative to the object 101.

[0085] The moving speed of the front end of robot 10 is based on the control command from control unit 21. On the other hand, the moving speed of the front end of robot 10 relative to object part 101 is calculated based on the amount of movement and time of movement of feature shapes and / or feature points within image data. For example... Figure 5 As shown, when the three feature shapes move from positions p11, p21, and p31 to positions p12, p22, p32, p13, p23, p33, and so on, respectively, the least squares method is used for fitting, and the moving speed of the three feature shapes is calculated accordingly. Alternatively, the average moving speed can be calculated by averaging the moving speeds of the three feature shapes.

[0086] When calculating the amount of movement, even if the feature shape and / or feature point used for follow control becomes invisible from the sensor 50, the control unit 21 can use the amount of movement calculated before the feature shape and / or feature point becomes invisible to make the front end of the robot 10 follow the object unit 101.

[0087] Furthermore, in the second control, the control unit 21 can also interpolate the detection results of the actual positions of the feature shapes and / or feature points using the calculated movement amount, the trend of the actual position detection results, etc. The actual positions of the feature shapes and / or feature points are calculated based on the image data actually captured by the sensor 50. Therefore, the acquisition period of the actual position becomes the same length as the shooting period of the sensor 50. In this regard, by interpolating the detection results, it is possible to detect or estimate the actual position between acquisition periods, estimate the future actual position, etc.

[0088] Through the aforementioned control, the control unit 21 causes the front end of the robot 10 to follow the object part 101. This positions the object part 101 at a predetermined position based on the captured data obtained by the sensor 50. For example, at this time, the horizontal position of the shaft 111a of the mounting portion 111 of the component 110 coincides with the horizontal position of the hole 101a in the object part 101.

[0089] As previously described, the coordinate system of sensor 50 is set to the reference coordinate system of robot 10, which operates based on motion program 23b. Therefore, the reference coordinate system of robot 10 moves in the transport direction of transport device 2, and this movement of the reference coordinate system coincides with the movement of the transport device 2 on item 100. In this case, the object portion 101 of item 100 is moving via transport device 2, but from the perspective of control unit 21, the object portion 101 appears to be stationary within the reference coordinate system.

[0090] Under this controlled state, the control unit 21 begins force control based on the force control program 23d (steps S1-5). Known force control methods can be used. In this embodiment, the robot 10 moves the component 110 in a direction that escapes the force detected by the force sensor 32. The amount of movement is determined by the control unit 21 based on the detection value of the force sensor 32.

[0091] For example, when the shaft 111a of the part 110 held by the hand 30 begins to engage with the hole 101a of the article 100, when the force sensor 32 detects a force in the opposite direction to the transport direction of the transport device 2, the robot 10 follows in the reference coordinate system and moves the part 110 slightly in the opposite direction to the transport direction to escape the detected force.

[0092] Next, when the position of the object part 101 relative to the robot 10 changes beyond a predetermined reference as detected sequentially by the sensor 50 (steps S1-6), the control unit 21 performs a first anomaly response operation (steps S1-7). Changes exceeding the predetermined reference include large movements of the object part 101 within the image data, and movements of the object part 101 within the image data faster than a predetermined speed. In cases of unstable power supply, the rotational speed of the motor 2a may sometimes decrease sharply, and sometimes the rotational speed of the motor 2a may fluctuate significantly. In these situations, the position of the object part 101 relative to the robot 10 may change beyond the predetermined reference.

[0093] As a first abnormality response, the control unit 21 performs actions such as shortening the control cycle of force control, increasing the sensitivity of force control, stopping the fitting process, and suspending the fitting operation. Shortening the control cycle of force control or increasing the sensitivity of force control enables the robot 10 to move more sensitively to the force applied to the component 110. In this embodiment, the control unit 21 performs actions such as suspending the fitting operation, stopping the transport device, or a combination of these actions.

[0094] Furthermore, when the detection value of the force sensor 32 exceeds a predetermined reference value (steps S1-8), the control unit 21 performs a second anomaly response operation (steps S1-9). When the detection value of the force sensor 32 exceeds the predetermined reference value, there is a high probability that an abnormal force is being applied to the component 110, the article 100, etc. Therefore, as a second anomaly response operation, the control unit 21 performs operations such as stopping the robot 10, moving the robot 10 at a low speed in the direction of the force detected by the free force sensor 32 to escape, stopping the handling device, or a combination of these operations. In this embodiment, the control unit 21 performs the operation of stopping the robot 10.

[0095] On the other hand, the control unit 21 determines whether the interlocking operation has ended (steps S1-10). When the interlocking operation ends, it sends control commands to the robot 10 and the hand 30 (steps S1-11). As a result, the hand 30 leaves the component 110 and moves to a standby position or a location where the next component 110 is stored via the robot 10.

[0096] Thus, in this embodiment, the position of the object portion 101 of the item 100 being transported by the transport device 2 relative to the front end of the robot 10 is sequentially detected by the sensor 50 mounted on the robot 10, and the robot 10 is controlled using the detection results of the sensor 50. Therefore, even without force control, the control unit 21 can identify the positional relationship between the component 110 supported by the robot 10 and the item 100, and can identify whether there is contact between the two. For example, even without force control, the control unit 21 can identify abnormalities in the transport device 2 where the amount of movement of the item 100 by the transport device 2 changes significantly. Therefore, without forcibly shortening the control cycle of force control or increasing the sensitivity of force control, damage prevention of the robot 10, transport device 2, item 100, etc., can be achieved, and the occurrence of vibration of the robot 10 can be suppressed.

[0097] In addition, in this embodiment, the control unit 21 uses the detection results of the sensor 50 to make the component 110 supported by the robot 10 follow the object 101, while using the detection value of the force sensor 32 to perform force control.

[0098] In this way, the control unit 21 uses the detection results of the sensor 50 to cause the component 110 of the robot 10 to follow the object part 101. Therefore, when the robot 10 performs a predetermined operation, the control unit 21 can accurately control the position and orientation of the component 110 supported by the robot 10 relative to the object part 101 of the item 100 being transported by the transport device 2. This is beneficial for preventing damage to the robot 10, transport device 2, item 100, etc., without shortening the control cycle of force control or increasing the sensitivity of force control, and also helps to suppress the occurrence of vibration of the robot 10.

[0099] Furthermore, in this embodiment, the work robot system includes a detection device 40 that detects at least the position of the object portion 101 of the item 100 on the handling device 2. Based on the detection result of the detection device 40, the control unit 21 moves the component 110 supported by the robot 10 closer to the object portion 101. If the robot 10 operates in this way based on the detection result of the detection device 40, the work efficiency is improved. At this time, the control unit 21 can also use the detection result of the work position detection device 2b to move the component 110 supported by the robot 10 closer to the object portion 101. By using the detection result of the work position detection device 2b, the control of the component 110 moving closer to the object portion 101 is made more accurate.

[0100] In this embodiment, the detection device 40 is a photoelectric sensor, but it can also be a two-dimensional camera, a three-dimensional camera, a three-dimensional distance sensor, or a sensor that measures shape by illuminating the object with light, positioned above, to the side, or below the transport device 2. When the detection device 40 is a two-dimensional camera, the control unit 21 can identify the position of the object part 101 of the item 100 being transported by the transport device 2, and can also identify its posture, based on the detection results, i.e., image data, from the detection device 40. Therefore, in steps S1-2, the control unit 21 can make the axis 111a of the component 110 more accurately approach the hole 101a of the object part 101.

[0101] Additionally, a machining tool can be supported at the front end of the robot 10, and the robot 10 performs a predetermined operation on the item 100 transported by the handling device 2. In this case, the machining tool is a drill bit, milling cutter, drilling and tapping tool, deburring tool, or other tools. In this case, in steps S1-2, the machining tool is brought close to the object part 101, and in steps S1-7, force control is performed based on the contact between the machining tool and the object part 101, thereby achieving the same effect as described above.

[0102] Furthermore, in steps S1-4, the control unit 21 can also use the position of the object part 101 in the image data, the moving speed of the object part 101 in the image data, and its direction, etc., to make the front end of the robot 10 follow the object part 101. Other known methods can also be used to make the front end of the robot 10 follow the object part 101. The same effect as described above is achieved when using this configuration.

[0103] Furthermore, as the transport device 2, a transport device that transports the item 100 along a curved path or a curved path can also be used. In these cases, the control unit 21 can also use the detection results of the sensor 50 to make the front end of the robot 10 follow the object part 101. In addition, in steps S1-6, when the position of the object part 101 relative to the robot 10 changes beyond a predetermined reference, in steps S1-7, the control unit 21 can perform a first abnormality response operation. Therefore, the same effect as described above is achieved when using the transport device.

[0104] Furthermore, the acquisition of movement in steps S1-4 is calculated based on image data actually captured by sensor 50. Therefore, if the acquisition period of movement is made consistent with the shooting period of sensor 50, the acquisition period of movement becomes the same length as the shooting period of sensor 50. In this regard, interpolation can also be performed on the movement calculated sequentially based on the shooting data of sensor 50. For example, control unit 21 uses the calculation results of multiple consecutive movement amounts to determine the trend of movement variation. Moreover, control unit 21 can set interpolated movement amounts between movement amounts along the determined trend.

[0105] In steps S1-9, as a second abnormality response operation, the control unit 21 can stop the motor 2a of the conveying device 2, decelerate the motor 2a of the conveying device 2, etc.

[0106] In this embodiment, a force sensor 32 is mounted on the front end of the robot 10. Alternatively, the force sensor 32 can be configured between the handling device 2 and the article 100, or inside the article 100. In this case, force control based on the detection value of the force sensor 32 can also be performed, achieving the same effect as described above.

[0107] Alternatively, the sensor 50 can be mounted on a part other than the wrist flange of the robot 10. In this case, the control unit 21 can also identify the positional relationship between the component 110 supported by the robot 10 and the item 100 transported by the handling device 2 based on the detection results of the sensor 50. Thus, the same effect as described above is achieved.

Claims

1. A work robot system, characterized in that, have: A transport device that moves items along a predetermined path; A robot that performs a predetermined operation on the object portion of the article being transported by the transport device; The control unit controls the robot; The first sensor is a vision sensor installed at the front end of the robot; A second sensor is positioned along the path; as well as The force detection unit detects the force generated by the contact between the object and a component or tool supported by the robot. The control unit is used for, The position of at least the object portion is obtained based on the output of the second sensor. Based on the obtained position, the robot-supported component or tool is controlled to move closer to the object. When the robot performs the predetermined task, while performing follow control to make at least the front end of the robot follow the object part, force control is performed based on the detection value of the force detection unit. The coordinate system of the first sensor is set as the coordinate system of the robot. The control unit moves the robot's coordinate system according to the motion of the object unit.

2. The work robot system according to claim 1, characterized in that, When the control unit is in a state where at least the front end of the robot is following the object part, it starts the force control and uses the robot to start bringing the component or the tool into contact with the object part to perform the predetermined operation.

3. The work robot system according to claim 1, characterized in that, The control unit calculates the movement amount of the target unit and uses the calculated movement amount for the following control as well.

4. The work robot system according to claim 1, characterized in that, When the position of the object relative to the robot changes beyond a predetermined reference as detected by the first sensor, at least one of the control unit and the handling device performs an abnormal response operation.

5. A work robot system, characterized in that, have: A transport device that moves items along a predetermined path; A robot that performs a predetermined operation on the object portion of the article being transported by the transport device; The control unit controls the robot; The first sensor is a vision sensor installed at the front end of the robot; A second sensor is positioned along the path; as well as The force detection unit detects the force generated by the contact between the object and a component or tool supported by the robot. The control unit is used for, The position of at least the object portion is obtained based on the output of the second sensor. Calculate the amount of movement of the object part. Based on the obtained position and the amount of movement, control is performed to bring the component or tool supported by the robot closer to the object. When the robot performs the predetermined task, while performing follow control to make at least the front end of the robot follow the object part, force control is performed based on the detection value of the force detection unit. When the position of the object relative to the robot, obtained based on the output of the first sensor, changes beyond a predetermined reference, the control unit shortens the control cycle of the force control.

6. The work robot system according to claim 5, characterized in that, The control unit performs the tracking control by placing the object part, the characteristic shape of the item, or the characteristic point of the item at a predetermined position within the field of view of the first sensor.

7. The work robot system according to claim 5, characterized in that, The control unit calculates the movement amount sequentially based on the output of the first sensor or the output of the detection device installed in the conveying device.

8. The work robot system according to claim 7, characterized in that, The control unit calculates an interpolated movement amount based on the plurality of movement amounts obtained by sequential calculation, and uses the acquired position, the movement amount, and the interpolated movement amount to perform the approach control.

9. The work robot system according to claim 5, characterized in that, The first sensor is a two-dimensional vision sensor.

10. The work robot system according to claim 9, characterized in that, When the control unit is in a state where at least the front end of the robot is following the object part, it starts the force control and uses the robot to start bringing the component or the tool into contact with the object part to perform the predetermined operation.

11. The work robot system according to claim 9, characterized in that, The predetermined path is a curved path or a winding path.

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