Robot system, method for controlling robot system, moving device, method for controlling moving device, method for manufacturing article, control program and recording medium

Abstract

To detect information on a state in a robot system while reducing consumption of power.SOLUTION: A robot system including a robot, and a moving device capable of mounting the robot has at least two sensors, and selects a sensor electrically driven in at least the two sensors, on the basis of information on the robot.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a robot and a moving device. [Background technology]

[0002] In recent years, by moving a robot system with a robot mounted on a movable platform to multiple work positions, it has become possible to handle multiple work processes such as part assembly work, part inspection work, and part processing work, thereby reducing the burden on production factory workers and reducing the number of personnel. In this type of robot system, a user moves the movable platform toward a fixed platform (work platform) on which a work object is placed, and makes the robot perform the work. In a robot system configured to be movable with a robot mounted on a movable platform, there is a possibility that the user may come into contact with the robot or the movable platform, or the user may cause the movable platform to come into contact with the fixed platform or peripheral equipment. In such cases, a robot system that can detect the presence or absence of contact that would be abnormal for the robot system is preferred. In the following Patent Document 1, a device is known in which a force sensor is provided on the robot and the force sensor detects contact with the robot. Furthermore, a first force sensor provided at the base end of the robot and a second force sensor provided at the tip of the robot are provided to estimate contact with the external environment. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-94935 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in order to improve the ease of movement by users, the robot system described above often uses a battery installed inside the mobile platform to drive the mounted robot. Therefore, if the sensor of the mobile platform is always turned on to detect contact between the robot and the external environment, the capacity of the mounted battery may be insufficient.

[0005] Thus, information regarding the state of a robot system is detected while reducing power consumption. [Means for solving the problem]

[0006] The present invention employs a robot system comprising a robot and a moving device on which the robot can be mounted, the robot system having at least two sensors, and selecting one of the at least two sensors to be electrically driven based on information about the robot. Effect of the Invention

[0007] According to the present invention, it is possible to detect information relating to a state in a robot system while reducing power consumption. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 illustrates a robot system 1000 according to an embodiment. [Diagram 2] FIG. 2 is a diagram showing a movable base 400 and a fixed base 700 in the embodiment. [Diagram 3] FIG. 1 is a schematic diagram of a robot system 1000 according to an embodiment. [Figure 4] FIG. 2 is a control block diagram of a robot system 1000 according to an embodiment. [Diagram 5] FIG. 2 is a control block diagram of a robot system 1000 according to an embodiment. [Figure 6] 3 is a control flowchart according to the embodiment. [Figure 7]FIG. 2 is a diagram showing a movable base 400 and a fixed base 700 in the embodiment. [Figure 8] FIG. 1 illustrates a robot system 1000 according to an embodiment. [Figure 9] FIG. 1 illustrates a robot system 1000 according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, the embodiments for carrying out the present invention will be described with reference to the accompanying drawings. Note that the embodiment shown below is merely an example, and for example, the detailed configuration can be appropriately changed by a person skilled in the art without departing from the spirit of the present invention. Also, the numerical values ​​taken up in the present embodiment are reference numerical values ​​and do not limit the present invention. Note that in the following drawings, the arrows X, Y, and Z in the figures indicate the overall coordinate system of the robot system. In general, the XYZ three-dimensional coordinate system indicates the world coordinate system of the entire installation environment. In addition, a local coordinate system may be appropriately used for the robot hand, fingers, joints, etc., depending on the convenience of control.

[0010] (First embodiment) FIG. 1 is a perspective view of a mobile robot system 1000 according to the present embodiment. As shown in FIG. 1, the robot system 1000 includes a robot arm 200 and a mobile platform 400. The mobile platform 400 may be referred to as a moving device. The mobile platform 400 is provided with a robot arm 200, which is a multi-jointed robot, on the upper surface (mounting surface) of the mobile platform 400, and wheels 401 for moving the mobile platform 400 are provided on the lower surface of the mobile platform 400. With the wheels 401 in contact with the floor surface (or ground), the user can operate the handle 403 to move the mobile platform 400 to an arbitrary position, thereby making it possible to move the robot arm 200 to an arbitrary position. The handle 403 may be referred to as an operating unit. The handle 403 may be adjustable to a height that is easy for the user to handle. The handle 403 may be made retractable into the mobile platform 400 so as to reduce the influence on the operation of the robot arm 200.

[0011] A plurality of fixed legs 402 are provided on the underside of the movable platform 400. In this embodiment, four fixed legs 402 are provided. Although not shown in Fig. 1, two more fixed legs 402 are provided on the back side of the page, and a grounding portion is provided at the portion that comes into contact with the floor surface.

[0012] Four wheels 401 are provided on the movable platform 400 (one is on the back side of the page in FIG. 1), and each of them moves up and down by a lift switch 405 arranged on the movable platform. In the state shown in FIG. 1, the wheels 401 are protruding from the movable platform 400, and the fixed legs 402 are not in contact with the floor. By pressing the lift switch 405 in the state shown in FIG. 1, the wheels 401 are stored in the movable platform 400, and the grounding parts of the fixed legs 402 come into contact with the floor.

[0013] As a result, after moving the mobile platform 400, the lift switch 405 is operated at the installation location to raise the wheels 401 and ground the fixed legs 402 on the ground, thereby maintaining the mobile platform 400 in a stopped state. When moving the mobile platform 400, the wheels 401 are moved in the -Z direction to release the mobile platform from contact with the floor surface, and when the mobile platform 400 is to be stopped at an arbitrary position, the fixed legs 402 are moved in the +Z direction to ground the suction parts of the fixed legs 402 on the floor surface. This makes it possible to easily release the mobile platform 400 from contact with the floor and fix it to the ground by the lift switch 405. In addition, a sensor such as an encoder (not shown) can be installed on the wheels 401, and the moving state of the mobile platform 400 can be detected by the sensor.

[0014] 1, the mobile platform 400 is provided with an area sensor 406 that recognizes the surrounding environment, and if the mobile platform 400 approaches a surrounding object during movement and is about to collide with it, a brake (not shown in FIG. 1) inside the mobile platform 400 is activated to avoid the collision. In the example of FIG. 1, two area sensors 406 are provided. After the robot system 1000 is installed, if the area sensor 406 detects that a user is nearby, the upper limit of the operating speed of the robot arm 200 is changed. In other words, when the robot arm 200 works alone, it operates at a high speed, and when working closely with a user, it operates at a slower speed than when the robot arm 200 works alone to ensure safety.

[0015] The movable platform 400 is also provided with an emergency stop switch 404 that immediately stops the operation of the robot arm 200 in the event of an abnormality. Also provided is an operation changeover switch 407 that is used when switching the operation of the robot arm 200 or the movable platform 400. For example, by pressing the operation changeover switch 407 before the user moves the movable platform 400, the robot arm 200 or the movable platform 400 can recognize that it is being moved by the user. When the robot system 1000 is to be stopped, pressing the operation changeover switch 407 allows the robot arm 200 or the movable platform 400 to recognize that the robot system 1000 has been stopped.

[0016] Although not shown in FIG. 1, an end effector for performing work can be provided at a predetermined position of the robot arm 200. As the end effector, various tools such as a robot hand, a screwdriver, a cutting / polishing tool, etc. may be provided. As the robot hand, an electric hand or an air hand driven by pneumatic pressure may be used. The end effector is attached to the robot arm 200 by a semi-fixed means (not shown) such as a screw fastener. Alternatively, it can be attached by a detachable means (not shown) such as a latch (ratchet) fastener. In particular, when the end effector is detachable, a method can be considered in which the robot arm 200 is controlled to detach or replace the end effector arranged at the supply position (not shown) by the operation of the robot arm 200 itself.

[0017] In this way, the robot arm 200 and the end effector can be moved to the corresponding work space (work table or fixed stand) by the moving stand 400, and an article can be manufactured by the end effector. The article is manufactured by grasping an object with the robot hand and assembling it to another object, disassembling an assembled object, tightening a screw with a screwdriver, and cutting or polishing with a tool.

[0018] 2 shows the movable platform 400 moved to the fixed platform 700, which is the work location. Power is supplied to the movable platform 400 by connecting a power cable to the power cable connection section 408 after the movable platform 400 has moved. After the movable platform 400 has moved and the power connection is complete, the robot arm 200 performs work on the fixed platform 700. On the fixed platform 700, a workpiece, a workpiece fixing jig, a workpiece supply machine, a hand exchange table, and the like (not shown) are placed depending on the work to be performed.

[0019] 3 is a schematic diagram of the robot system 1000 of this embodiment in the XZ plane. A robot control device 300, a PLC (Programmable Logic Controller) 500, and an external input device 600 are arranged inside the moving platform 400. The robot control device 300 is connected to drive devices (not shown in FIG. 3) installed on each axis of the robot arm 200 by power cables, communication cables, etc., and each joint is rotated by controlling the drive devices. The robot control device 300 is equipped with a power supply device 350 and a host control device 340. Each axis is also equipped with an encoder (not shown in FIG. 3) that detects the relative movement amount of the structure, and it is possible to control the operation of the robot arm 200 by controlling the rotation direction and rotation amount of the joint.

[0020] In addition, an external input device 600 is provided as a teaching device that transmits teaching data to the robot control device 300. An example of the external input device 600 is a teaching pendant, which is used by the user to specify the position and posture of the robot arm 200 and the position and posture of the end effector. Such an external input device is mounted on a mobile platform 400 so that it can be moved.

[0021] The external input device 600 is provided with an operation unit including operation keys for, for example, controlling the posture (position and angle) of the joints of the robot arm 200 or moving the end effector of the robot arm 200. When some operation is performed on the operation unit of the external input device 600, the robot control device 300 transmits a signal to the drive device of each joint in response to the operation of the external input device 600, and controls the operation of the robot arm 200 or the end effector. At that time, the robot control device 300 executes a robot control program including a control program described below, thereby controlling each part of the robot arm 200.

[0022] As shown in FIG. 3, the robot arm 200 of this embodiment is configured with six-axis articulated joints. The robot arm 200 has a base 210 and six links 201, 202, 203, 204, 205, and 206. The links 201 to 206 are rotated by six drive devices (not shown in FIG. 3) that rotate around the arrows indicated by joint axes A1, A2, A3, A4, A5, and A6. Each drive device (not shown in FIG. 3) is equipped with a motor and a reducer that reduces the output of the motor. In this embodiment, a strain wave gear reducer is used. That is, the motor provided in the drive device (not shown in FIG. 3) serves as a drive source that generates a drive force that displaces each of the links 201 to 206 to which each joint is connected. Each motor also has an encoder (not shown in FIG. 3) built in that detects the rotation angle of the motor itself. Further, each joint is provided with torque sensors 221, 222, 223, 224, 225, and 226 capable of acquiring information related to torque. At least two torque sensors are provided.

[0023] With the above configuration, the end effector can be operated to any position by the robot arm 200 to perform a predetermined task. For example, a predetermined workpiece and another workpiece can be used as materials, and a process of assembling the predetermined workpiece and the other workpiece can be performed to produce an assembled workpiece as a result. In addition, when the predetermined workpiece and the other workpiece are assembled, one of the workpieces can be removed and disassembled. In this manner, an article can be manufactured by the robot system 1000.

[0024] Fig. 4 is a control block diagram of the robot system 1000 in this embodiment. The host control device 340 of the robot control device 300 is configured with a computer including a microprocessor and the like, and can control the robot arm 200 and an end effector (not shown). As shown in Fig. 4, the computer constituting the robot control device 300 has a CPU (Central Processing Unit) 302. It also has a ROM (Read Only Memory) 303 and a RAM (Random Access Memory) 304. It further includes a communication interface (hereinafter, "I / F") 301, a HDD (Hard Disc Drive) 306, and the like. The CPU 302, which is a processor, is an example of a control unit.

[0025] A program 330 is recorded in the ROM 303. The program is a basic program such as a BIOS for causing a computer, i.e., a CPU 302, to execute a control method and arithmetic processing of the robot arm 200 and the end effector. The RAM 304 is used to temporarily store data such as teaching data input from an external input device, control commands, and data from the PLC 500. The HDD 306 is a storage unit that stores various data resulting from arithmetic processing by the CPU 302. The recording disk drive 305 can read out various data and control programs recorded in the recording disk 331. The CPU 302 acquires data from the external input device 600, data from various sensors mounted on the robot arm 200, the end effector, and the moving platform 400, data from the PLC 500, and instructions from the emergency stop switch 404 through the I / F 301 and the bus 307. In addition, an external storage device such as a monitor on which various images are displayed, a rewritable non-volatile memory, and an external HDD may be mounted.

[0026] The host controller 340 is daisy-chained to the motor control boards 241 provided at the joints via communication cables. The host controller 340 transmits commands to the motor control boards 241. The motor control boards 241 then use the corresponding motor drive boards 251, 252, 253, 254, 255, 256 to perform distributed control of the corresponding motors 231, 232, 233, 234, 235, 236. The host controller 340 acquires (calculates) a trajectory of the robot arm 200 to realize an operation according to instruction from the external input device 600.

[0027] The host controller 340 transmits various commands to each motor control board 241, such as an operation command (specifically, a position command) for instructing the operation of each motor 231-236 based on the result of the trajectory calculation, an operation execution start command for instructing the start of execution of an operation based on the operation command, a synchronization command, etc. The weight of each link 201-206 is stored in the ROM 303 of the host controller 340. Then, the CPU 302 acquires (calculates) the posture of the robot arm 200 from the encoders 211, 212, 213, 214, 215, 216 of each axis.

[0028] When the emergency stop switch 404 is pressed by the user, the CPU 302 transmits a command to each motor control board 241 to stop the robot arm 200, and activates a brake (not shown) provided at each joint. When the area sensor 406 detects the presence of a user, the CPU 302 transmits a speed range for operating each joint to each motor control board 241, and controls the motors 231 to 236 at the speed within the transmitted range. When the area sensor 406 detects the possibility of the robot system 1000 colliding with an object, the CPU 302 transmits a command to each motor control board 241 to stop the robot arm 200, and activates a brake (not shown) provided at each joint. When the CPU 302 acquires data indicating that the work process has changed from the PLC 500, the CPU 302 transmits a command to the motor control board 241 to control the robot arm 200 using teaching data corresponding to the work process to be executed.

[0029] Similarly, the PLC 500 is also composed of a computer including a microprocessor and the like. The computer constituting the PLC 500 has a CPU, a ROM, a RAM, and a HDD, just like the upper controller 340. It further includes an I / F and the like. The PLC 500 manages the work process and controls the wheels 401 of the moving platform 400. The position of the wheels 401 is controlled when the lift switch 405 is pressed by the user. The operation changeover switch 407 is pressed by the user to detect whether the moving platform 400 is being moved by the user or not, and transmits the information to the upper controller 340. The PLC 500 also obtains information on the state of the robot arm 200 (arm posture and end effector posture) from the upper controller 340. Note that all of the various switches and area sensors may be provided in the robot arm 200, or all of them may be provided in the moving platform 400.

[0030] The torque sensors 221-226 are provided with a structure and an optical encoder that detects the amount of relative movement of the structure. When the robot arm 200 is in operation, the optical encoder detects the amount of relative movement of the structures of the torque sensors 221-226 that accompanies the relative displacement of each of the links 201-206. Based on the input torque command value, the motor control board 241 outputs a current command to each of the motors 231-236 via the motor drive boards 251-256 to control the operation of each of the motors 231-236 so that the torque detected by the torque sensor of each joint follows the command value.

[0031] The external input device 600 may be, for example, an operating device such as a teaching pendant (TP), but may also be another computer device (PC or server) capable of editing a robot program. The external input device 600 can be connected to the upper control device 340 via a wired or wireless communication connection means, and has a user interface function such as robot operation and status display. The target joint angles of each joint input by the external input device 600 are output to the CPU 302 via the I / F 301 and the bus 307.

[0032] The CPU 302 receives teaching point data input, for example, by the external input device 600. Also, based on the teaching point data input from the external input device 600, it can generate trajectories for each axis of the robot arm 200 and transmit the trajectories to each motor control board 241 via the bus 307. The CPU 302 outputs drive command data indicating the control amount of the rotation angle of each of the motors 231 to 236 to each motor control board 241 via the bus 307 at predetermined intervals.

[0033] The motor control board 241 calculates the amount of current output to each of the motors 231-236 based on the drive command input from the CPU 302, and supplies current to each motor using the motor drive boards 251-256 to control the joint angle of each joint. Also, detection signals from each of the encoders 211-216 and the torque sensors 221-226 are output to the CPU 302 via the bus 307. That is, the CPU 302 executes feedback control of each of the motors 231-236 via the motor control board 241 so that the current joint angle values ​​of the joints detected by each of the encoders 211-216 become the target joint angles. Similarly, it executes feedback control of each of the motors 231-236 so that the current torque values ​​of the joints detected by each of the torque sensors 221-226 become the target torques.

[0034] Furthermore, by returning the outputs of the torque sensors 221-226 to the upper control device 340 and feeding them back to the drive of each of the motors 231-236, the torque applied to each of the links 201-206 during drive can be controlled. Furthermore, the force generated in the link 206 of the robot arm 200 can be obtained by calculation from the values ​​of each of the torque sensors 221-226, making it possible to feedback control the load applied to the parts to be assembled. Note that although the present embodiment will be described taking a torque sensor as an example, information regarding the load applied to the robot system may be obtained by a sensor other than a torque sensor. For example, various sensors such as a current sensor, a proximity sensor, a contact sensor, an acceleration sensor, an imaging device, etc. may be used.

[0035] When a robot hand is used as an end effector (not shown), host control device 340 may also be connected to a hand motor (not shown) via an interface and a hand motor driver. The hand motor driver calculates the amount of current output to the hand motor based on a drive command received from CPU 302, and supplies current to the hand motor to control the speed of the hand motor. It also outputs a pulse signal from the encoder of the hand motor to CPU 302 via the interface and bus. That is, CPU 302 executes feedback control of the hand motor via the hand motor driver so that the current value of the hand motor speed detected by the encoder becomes the target speed.

[0036] FIG. 5 is a diagram showing details of the control blocks of the motor control board 241 and the motor drive boards 251-256 in this embodiment. In FIG. 5, the motor control board 241 and the motor drive boards 251-256 are shown as one block, but the motor control board 241 and the motor drive boards 251-256 are provided corresponding to each joint. The ratio of the number of the motor control board 241 to the number of the drive boards 251-256 is configured to be 1:1. In other words, the motor control board 241 uses a board with the same specifications for each joint, and the specifications of the motor drive boards 251-256 are changed according to the motor output of each joint. The motor control board 241 and the drive boards 251-256 are configured to mount the communication driver 103, the power supply circuit 104, the control circuit 105, and the inverter 106. The motor drive boards 251-256 and the motor control board 241 are electrically connected, for example, by an inter-board connector, a cable, a flexible flat cable, or the like.

[0037] The host controller 340 is daisy-chained to each motor control board 241 via the serial communication line 130. The host controller 340 controls each motor 231-236 by transmitting commands to the motor control board 241. The host controller 340 calculates (acquires) a trajectory of the robot arm 200 to realize an operation taught by the external input device 600. The host controller 340 transmits various commands to each motor control board 241, such as an operation command (specifically, a position command) that instructs the operation of each rotary motor based on the result of the trajectory calculation, an operation execution start command that instructs the start of execution of an operation based on the operation command, and a synchronization command.

[0038] The power supply device 350 supplies power to each of the motor control boards 241 and each of the motor drive boards 251-256 (motor drive boards 253-255 are not shown because they are omitted) via the power cable 140. Similarly, the power supply device 350 also supplies power to the torque sensors 221-226. Based on instructions from the motor control board 241, the motor drive boards 251-256 that have been supplied with power supply power to each of the motors 231-236 to drive them.

[0039] Each motor control board 241 and motor drive board 251 is connected to the upper controller 340 via a serial communication line 130 and a communication connector 120. The communication connector 120 functions as a communication IF. Various commands are transmitted as signals to each motor control board 241 by serial communication via the serial communication line 130 in a communication protocol such as CAN (Controller Area Network). In addition, status notifications and the like are transmitted and received between the upper controller 340 and each motor control board 241 via the serial communication line 130.

[0040] Each of the motor control boards 241 and the motor drive boards 251 includes a communication driver 103 that receives signals indicating various commands from a higher-level control device 340, and a power supply circuit 104 that converts a voltage applied by a power supply device 350 into a predetermined DC voltage. The power supply device 350 is connected to the control circuit 105 through a power cable 140 and a power supply connector 119. The power supply connector 119 functions as a power supply IF. The control circuit 105 is composed of a microcomputer and has a plurality of switching elements. The control circuit 105 includes a calculation unit 111, a communication control unit 112, a memory 113, a clock generation unit 114, a timer 115, a PWM waveform generation unit 116 (Pulse Width Modulation), an AD conversion unit 117, and a counter 118. In this embodiment, the motor is driven by the PWM waveform generation unit 116 and the inverter 106.

[0041] Also, a current detection unit 107 is provided to detect a current flowing from the inverter 106 to the motor 231 (specifically, the windings of the motor). The current detection unit 107 outputs a current value indicating the current detection result as a voltage. In other words, the current detection unit 107 outputs a voltage whose value is proportional to or corresponds to the current value.

[0042] Further, the counter 118 acquires the detection result of the encoder 211 that detects the rotational position of the motor 231, specifically the rotational position of the rotor of the motor (in other words, the rotation angle). The encoder 211 is, for example, a rotary encoder, and outputs pulses according to the rotation of the rotor. The counter 118 counts the number of pulses output by the encoder 211. Then, the counter 118 outputs the count result to the calculation unit 111 as rotational position information of the motor (hereinafter simply referred to as position information). In this way, the counter 118 detects the rotational position of the motor by counting the number of pulses of the encoder 211. Although not shown in FIG. 5 for the sake of simplicity of explanation, it is also assumed that a counter that acquires the detection results of the torque sensors 221 to 226 is separately provided.

[0043] The communication control unit 112 controls storage of various command data input from the communication driver 103 in the memory 113. The memory 113 is a storage unit such as a RAM, and stores the received various command data under the control of the communication control unit 112. The clock generation unit 114 is, for example, a crystal oscillator, and generates and outputs a clock signal with a specific oscillation frequency. The timer 115 measures time based on the clock signal generated by the clock generation unit 114, and outputs the measured time result to the calculation unit 111.

[0044] The calculation unit 111 is, for example, a CPU, and performs calculation processing in accordance with a processing program stored in a non-volatile memory (not shown) based on various commands from the upper control device 340, current information indicating the current detection result, and position information indicating the position detection result. As part of the calculation processing, the calculation unit 111 calculates a drive command to be output to the PWM waveform generation unit 116. Then, the calculation unit 111 outputs the drive command to the PWM waveform generation unit 116 when the calculation of this drive command is completed.

[0045] The PWM waveform generating unit 116 receives a drive command input from the calculation unit 111 and generates a PWM signal to be output to the gate terminal (base terminal) of each switching element of the inverter 106. The inverter 106 pulse-width modulates the supplied DC voltage by switching operations of the switching elements by the PWM signal and outputs the modulated voltage to the motor 231. As a result, an AC current, for example, a three-phase AC current, is output to the motor 231. The above-described operations of the PWM waveform generating unit 116 and the inverter 106 drive the motor 231 according to the input drive command. That is, the PWM waveform generating unit 116 and the inverter 106 supply a current to the motor 231 according to the input drive command.

[0046] The AD conversion unit 117 converts the output voltage (analog signal) indicating the current value from the current detection unit 107 into a digital signal recognizable by the calculation unit 111, and outputs the current information converted into the digital signal to the calculation unit 111. The calculation unit 111 monitors the behavior of the robot arm 200, that is, the rotational position and current of the motor 231, and performs feedback control based on a command received from the upper control device 340 to control the drive of the motor 231. Specifically, the calculation unit 111 executes a calculation process to calculate a drive command for controlling the position, speed, and current (torque) of the motor by position, speed, and current control processing based on the current information from the current detection unit 107 and the position information acquired by the encoder 211.

[0047] The drive mode of each motor control board 241 and motors 231 to 236 can be set individually in response to a command from the upper control device 340. For example, the control circuit 105 has a sleep mode and can perform processing with some of the above operations restricted in response to a command. The power supply circuit 104 can perform ON / OFF control in response to a command. This allows the upper control device 340 to perform power control for each joint in response to a command. The robot arm 200 operates in the above manner.

[0048] 6 is a flowchart showing the steps of the control method of the robot system 1000 in this embodiment. The host controller 340 and the PLC 500 execute corresponding control programs and communicate with each other, thereby executing the flowchart in FIG.

[0049] 6, first, in step S1, the host controller 340 determines whether the mobile platform 400 is moving. As a method for determining whether the mobile platform 400 is moving, the host controller 340 may recognize the pressing of the operation changeover switch 407 via the PLC 500, or may detect and recognize information from a sensor (caster operation detection device) installed on the wheel 401 via the PLC 500.

[0050] If the result of judging whether the mobile platform 400 is moving or not, the host controller 340 judges that the mobile platform 400 is moving, and proceeds from step S1: YES to step S2, where the process moves to the step of selecting the sensor to be electrically driven. If the mobile platform 400 is not moving, it is considered that a power cable is connected to the power cable connection part 408 of the mobile platform 400, and therefore it is considered that sufficient power can be supplied. Therefore, from step S1: NO, the process proceeds to step S5, where all the torque sensors 221-226 provided on the robot arm 200 are electrically driven. Then, the process returns to the state immediately before step S1. Here, electrically driving means turning off the power of the torque sensors, or putting them into a state that is not a state in which power consumption is reduced by sleep mode or the like.

[0051] Next, in step S2, the host controller 340 selects the torque sensors 221-226 to be electrically driven based on the information of the robot arm 200. The torque sensors 221-226 are selected to detect the torque acting on the links where the robot arm 200 is likely to interfere with the surrounding objects (where a load is assumed to occur) due to the movement of the moving platform 400. The links where interference is likely to occur due to the movement of the moving platform 400 change depending on the posture of the robot arm 200 while the moving platform 400 is moving, so information on the posture of the robot arm 200 is required. If the posture of the robot arm 200 is fixed while the moving platform 400 is moving, the links where interference is likely to occur are determined to be predetermined links, so the torque sensor to be powered may be determined in advance. Also, the links where a load is assumed to occur may be set by learning by performing a series of operations to move the moving platform 400 to the fixed platform 70 multiple times. In this embodiment, each joint is provided as an independent control unit, such as each motor control board 241 and each motor 231 to 236, making it easy to electrically drive them individually.

[0052] An easier method of selection is to electrically drive the torque sensors 221-226 that acquire load information in the three directions and select a posture that allows detection of torque in three independent directions. Since the robot system 1000 is installed in a three-dimensional space of XYZ, an abnormality occurring in the robot arm 200 can be detected with high accuracy by detecting torque in three independent directions. It is desirable that the torque in the three independent directions be mutually orthogonal as much as possible.

[0053] Next, in step S3, the host controller 340 judges whether or not an abnormality has occurred in the robot system 1000 based on the value of the selected torque sensor. The judgment method may be to judge an abnormality when at least one of the torque sensors selected in step S2 falls outside a preset threshold range, or to judge an abnormality comprehensively by adding up the values ​​of multiple torque sensors. If step S3: YES, proceed to step S4. If step S3: NO, proceed to step S6 to allow the user to continue moving the mobile platform 400. Then, return to the state immediately before step S3 and judge whether or not an abnormality has occurred in the robot system 1000.

[0054] In step S4, the user is notified of the abnormality. The method of notifying the abnormality may be a device that the user can recognize, such as a light-emitting device composed of an LED (Light Emitting Diode). The abnormality may be displayed on the monitor of the external input device 600 or another monitor. The abnormality may also be notified using an audio device. Since the user operates the handle 403 to move the mobile platform 400, it is preferable to place the LED at the joint of the robot arm 200 from the viewpoint of visibility. In this way, it is determined whether to continue the work depending on the abnormal state of the selected torque sensor 221-226. If an abnormality is detected, the wheels 401 may be locked and switched to a stopped state via the PLC 500 to stop the user from moving the mobile platform 400. Then, when the user removes the cause of the abnormality, the user may press the operation changeover switch 407 to resume the user's movement of the mobile platform 400. If the degree of the abnormality is minor, the wheels 401 may not be locked and the abnormality may be notified.

[0055] According to the present embodiment, the sensor required to obtain information on an abnormality in the robot system 1000 is selectively electrically driven based on the information of the robot arm 200. Therefore, an abnormality in the robot system can be detected while reducing power consumption. In the present embodiment, an example of selecting a torque sensor to be electrically driven based on the information of the robot arm 200 has been described, but the links 201 to 206 may be selected. Each of the links 201 to 206 can be driven in a direction in which the contact force decreases according to the torque based on the torque sensors 221 to 226. This makes it possible to provide a robot system 1000 that is safe for the user. Although the case where an abnormality is notified to the user has been described, the present invention is not limited to this. For example, when the selection of the torque sensor to be electrically driven is completed in step S2, the user may be notified that the preparation for movement is completed by a display device such as a monitor or a voice device, such as "You may disconnect the power cable from the moving platform."

[0056] Second Embodiment Next, a method for selecting an electrically driven torque sensor in the second embodiment will be described. In this embodiment, a method for selecting a torque sensor based on the traveling direction (moving direction) of the moving platform 400 will be described in detail. In the following, the same reference symbols will be used for configurations that are the same as or equivalent to those in the above-mentioned embodiment, and their description will be omitted or simplified, and differences from the above-mentioned embodiment will be mainly described.

[0057] Fig. 7 is a diagram for explaining a method for selecting an electrically driven torque sensor in this embodiment. Fig. 7 shows a state in which a user carries the movable platform 400 and moves it toward the fixed platform 700. The arrow shown in Fig. 7 indicates the moving direction of the movable platform 400. For ease of explanation, a three-joint robot arm having links 2001, 2002, and 2003 is shown as an example of the robot arm 200, and it is assumed that each joint has a torque sensor.

[0058] As shown in FIG. 7, an abnormality occurring in the robot system 1000 often appears as a load occurring in the traveling direction of the mobile platform 400. For example, if the mobile platform 400 is moved and collides with the fixed platform 700, the mobile platform 400 may suddenly accelerate or decelerate, generating an acceleration load greater than expected. Therefore, in order to detect the presence or absence of an abnormality, a torque sensor that detects the load in the traveling direction of the mobile platform 400 may be selected and electrically driven. In FIG. 7, the tangent direction of the torque detection direction of the torque sensor installed on the link 2002 coincides with the traveling direction of the mobile platform 400. Therefore, in this embodiment, the torque sensor installed on the joint between the link 2001 and the link 2002 is electrically driven to execute the flowchart detailed in FIG. 6.

[0059] According to the present embodiment, the torque sensor installed at the joint between the link 2001 and the link 2002 is selected and electrically driven, thereby reducing power consumption and detecting the presence or absence of an abnormality in the robot system 1000. In addition, the traveling direction of the mobile platform 400 can be recognized by a sensor (caster motion detection device) installed on the wheel 401. Therefore, it is possible to change the electrically driven torque sensor in real time according to the traveling direction of the mobile platform 400, and it is also possible to improve the accuracy of detecting an abnormality. In addition, the above-mentioned various embodiments and modified examples may be combined and implemented.

[0060] (Third embodiment) Next, a method for selecting an electrically driven torque sensor in the third embodiment will be described. In this embodiment, a method for selecting a torque sensor when the robot arm 200 has a part that protrudes from an area based on the upper surface of the moving platform 400 (the mounting surface of the robot arm 200) will be described in detail. Note that in the following, the same reference numerals will be used for configurations that are the same as or equivalent to those in the above-mentioned embodiment, and their description will be omitted or simplified, and differences from the above-mentioned embodiment will be mainly described.

[0061] Fig. 8 is a diagram for explaining a method for selecting an electrically driven torque sensor in this embodiment. As in Fig. 7, the robot arm 200 is a three-joint robot arm having a link 2001, a link 2002, and a link 2003, and each joint has a torque sensor.

[0062] The arrows in FIG. 8 indicate the width in the X direction of the top surface of the movable platform 400. Furthermore, the area S1 is a predetermined area extending in the Z direction of the top surface of the movable platform 400. When the robot arm 200 is contained in the area S1, it is difficult for an abnormality to occur in the robot system 1000 unless some object intentionally enters the area S1 of the movable platform 400. On the other hand, when a predetermined part of the robot arm 200 protrudes from the area S1, there is a high possibility that an abnormality will occur due to a user or a surrounding object colliding with the protruding predetermined part. In FIG. 8, the link 2001 and the robot hand correspond to this. Therefore, in this embodiment, a torque sensor installed in a joint between the link 2001 and the robot hand is electrically driven to execute the flowchart detailed in FIG. 6.

[0063] According to the present embodiment, the torque sensor installed at the joint between the link 2001 and the robot hand is selected and electrically driven, thereby making it possible to detect the presence or absence of an abnormality in the robot system 1000 while reducing power consumption. In addition, since the torque sensor corresponding to the portion protruding from the region S1 is electrically driven, it is also possible to reduce the number of torque sensors to be electrically driven. In addition, since the portion protruding from the region S1 is more likely to interfere with the user or surrounding objects than the portion not protruding from the region S1, it is possible to effectively detect an abnormality. In addition, the above-mentioned various embodiments and modified examples may be combined and implemented.

[0064] (Fourth embodiment) Next, a method for selecting an electrically driven torque sensor in the fourth embodiment will be described. In this embodiment, a method for selecting a torque sensor when the robot arm 200 has a part that protrudes from the area based on the area sensor 406 mounted on the moving platform 400 will be described in detail. In the following, the same reference numerals will be used for configurations that are the same as or equivalent to those in the above-mentioned embodiment, and their description will be omitted or simplified, and differences from the above-mentioned embodiment will be mainly described.

[0065] Fig. 9 is a diagram for explaining a method for selecting an electrically driven torque sensor in this embodiment. As in Fig. 7 and Fig. 8, a robot arm 200 is a three-joint robot arm having a link 2001, a link 2002, and a link 2003, and each joint has a torque sensor.

[0066] As shown in FIG. 9, the area sensor 406 can issue an alert when, for example, a user or a surrounding object enters a set range. The arrows shown in FIG. 9 indicate the length of the range in the X direction set in the area sensor 406. Furthermore, the area S2 is a predetermined area extending in the Z direction of the range in the XY plane set in the area sensor 406. When the robot arm 200 is contained in the area S2, it is difficult for an abnormality to occur in the robot system 1000 unless some object intentionally enters the area S2 on the moving platform 400. On the other hand, when a predetermined part of the robot arm 200 protrudes from the area S2, there is a high possibility that an abnormality will occur due to a user or a surrounding object colliding with the protruding predetermined part. In FIG. 9, the link 2001 and the robot hand correspond to this. Therefore, in this embodiment, a torque sensor installed in a joint between the link 2001 and the robot hand is electrically driven to execute the flowchart detailed in FIG. 6.

[0067] According to the present embodiment, the torque sensor installed at the joint between the link 2001 and the robot hand is selected and electrically driven, thereby making it possible to detect the presence or absence of an abnormality in the robot system 1000 while reducing power consumption. Furthermore, since the torque sensor corresponding to the portion protruding from the region S2 is electrically driven, it is also possible to reduce the number of torque sensors to be electrically driven. Furthermore, since the portion protruding from the region S2 is more likely to interfere with the user or surrounding objects than the portion not protruding from the region S2, it is possible to effectively detect an abnormality. Furthermore, the above-mentioned various embodiments and modified examples may be combined and implemented.

[0068] (Other embodiments) The processing procedures of the above-described embodiments are specifically executed by input from each CPU and the user. Therefore, it is also possible to configure the system to read and execute a recording medium on which a software program capable of executing the above-described functions is recorded. In this case, the program itself read from the recording medium realizes the functions of each of the above-described embodiments, and the program itself and the recording medium on which the program is recorded constitute the present invention. In addition, the control flowchart described in FIG. 6 may be executed by a control device that controls the moving platform 400, and may be implemented as a moving device or a control method for a moving device.

[0069] In each embodiment, the computer-readable recording medium is a ROM, a RAM, or a flash ROM, and the control program is stored in the ROM, the RAM, or the flash ROM. However, the present invention is not limited to such an embodiment. The program for implementing the present invention may be recorded in any recording medium as long as the recording medium is computer-readable. An SSD (Solid State Drive) may be used as the storage unit.

[0070] In the various embodiments described above, the robot arm 200 is an articulated robot arm having a plurality of joints, but the number of joints is not limited to this. Although a vertical multi-axis configuration has been shown as the type of robot arm, the same configuration as above can be implemented with different types of joints, such as a horizontal multi-joint type, a parallel link type, or an orthogonal robot.

[0071] Furthermore, the various embodiments described above can be applied to machines that can automatically perform movements such as extension, contraction, bending, vertical movement, horizontal movement, or rotation, or a combination of these movements, based on information stored in a memory device provided in the control device.

[0072] The present invention is not limited to the above-described embodiment, and many modifications are possible within the technical concept of the present invention. The effects described in the embodiments of the present invention are merely a list of the most preferable effects resulting from the present invention, and the effects of the present invention are not limited to those described in the embodiments of the present invention. The above-described various embodiments and modifications may be combined and implemented.

[0073] The disclosure of this embodiment also includes the following configurations and methods.

[0074] (Configuration 1) A robot system including a robot and a moving device capable of mounting the robot, having at least two sensors; selecting a sensor to be electrically driven from among the at least two sensors based on information about the robot; A robot system comprising:

[0075] (Configuration 2) In the robot system according to configuration 1, The information about the robot is information about a position or a posture of the robot. A robot system comprising:

[0076] (Configuration 3) In the robot system according to configuration 1 or 2, selecting a sensor to be electrically driven from among the at least two sensors based on information regarding a posture of the robot when the moving device is being moved; A robot system comprising:

[0077] (Configuration 4) In the robot system according to any one of configurations 1 to 3, selecting a sensor to be electrically driven from among the at least two sensors when the moving device is being moved; A robot system comprising:

[0078] (Configuration 5) In the robot system according to any one of configurations 1 to 4, selecting a sensor to be electrically driven from among the at least two sensors based on an area set based on a placement surface of the robot in the moving device and information about the robot; A robot system comprising:

[0079] (Configuration 6) In the robot system according to any one of configurations 1 to 5, selecting a sensor to be electrically driven from among the at least two sensors based on a region set based on a range of an area sensor provided on the moving device and information related to the robot; A robot system comprising:

[0080] (Configuration 7) In the robot system according to configuration 5 or 6, electrically driving a sensor capable of acquiring information regarding a portion protruding from the region in the at least two sensors; A robot system comprising:

[0081] (Configuration 8) In the robot system according to any one of configurations 1 to 7, selecting a sensor to be electrically driven from among the at least two sensors based on a moving direction of the moving device; A robot system comprising:

[0082] (Configuration 9) In the robot system according to any one of configurations 1 to 8, electrically driving sensors capable of obtaining information about the load on the robot in three independent directions; A robot system comprising:

[0083] (Configuration 10) In the robot system according to any one of configurations 1 to 9, electrically driving a sensor capable of acquiring a load acting on the robot in the moving direction of the moving device; A robot system comprising:

[0084] (Configuration 11) In the robot system according to any one of configurations 1 to 10, The at least two sensors are provided on the robot, Each of the at least two sensors is capable of being independently electrically driven. A robot system comprising:

[0085] (Configuration 12) In the robot system according to any one of configurations 1 to 11, a switch for detecting when the mobile device is moving; A robot system comprising:

[0086] (Configuration 13) In the robot system according to any one of configurations 1 to 12, A motion detection device is provided on the wheels of the mobile device to detect that the mobile device is moving. A robot system comprising:

[0087] (Configuration 14) In the robot system according to any one of configurations 1 to 13, When an abnormality is detected based on the electrically driven sensor, the occurrence of the abnormality is notified to a user using at least one of a display device, an audio device, and a light-emitting device. A robot system comprising:

[0088] (Configuration 15) In the robot system according to any one of configurations 1 to 14, notifying a user that preparation for movement of the mobile device has been completed using at least one of a display device, an audio device, and a light-emitting device; A robot system comprising:

[0089] (Configuration 16) In the robot system according to configuration 15, When the selection of the sensor to be electrically driven is completed, notifying the user by using at least one of a display device and an audio device that it is OK to disconnect the power cable from the mobile device. A robot system comprising:

[0090] (Configuration 17) 17. The robot system according to any one of configurations 1 to 16, the robot is a robot arm, and the at least two sensors are torque sensors that obtain information about torques at joints of the robot arm; A robot system comprising:

[0091] (Method 18) 18. A method for manufacturing an article, comprising the steps of: manufacturing an article using the robot system according to any one of configurations 1 to 17.

[0092] (Method 19) A method for controlling a robot system including a robot and a moving device capable of mounting the robot, comprising the steps of: having at least two sensors; selecting a sensor to be electrically driven from among the at least two sensors based on information about the robot; A control method comprising:

[0093] (Configuration 20) A mobile device capable of mounting a robot having at least two sensors, selecting a sensor to be electrically driven from among the at least two sensors based on information about the robot; A mobile device comprising:

[0094] (Method 21) A method for controlling a mobile device capable of mounting a robot having at least two sensors, comprising the steps of: selecting a sensor to be electrically driven from among the at least two sensors based on information about the robot; A control method comprising:

[0095] (Configuration 22) A control program capable of executing the control method according to Method 19 or 21 by a computer.

[0096] (Configuration 23) A computer-readable recording medium storing the control program according to configuration 22. [Explanation of symbols]

[0097] 200 Robot Arm 201, 202, 203, 204, 205, 206, 2001, 2002, 2003 Links 210 Foundation 211, 212, 213, 214, 215, 216 Encoders 221, 222, 223, 224, 225, 226 Torque Sensors 231, 232, 233, 234, 235, 236 Motors 241 Motor control board 251, 252, 253, 254, 255, 256 Motor drive board 300 Robot control device 340 Upper control device 350 power supply 400 Mobile stand 401 wheels 402 Fixed leg 403 Handle 404 Emergency stop switch 405 Lift switch 406 Area Sensor 407 Operation Switch 408 Power cable connection 500 PLC(Programmable Logic Controller) 600 External Input Device 700 Fixed stand 1000 Robot System S1, S2 area

Claims

1. A robot system including a robot and a moving device capable of mounting the robot, having at least two sensors; selecting a sensor to be electrically driven from among the at least two sensors based on information about the robot; A robot system comprising:

2. 2. The robot system according to claim 1, The information about the robot is information about a position or a posture of the robot. A robot system comprising:

3. 3. The robot system according to claim 1, selecting a sensor to be electrically driven from among the at least two sensors based on information regarding a posture of the robot when the moving device is being moved; A robot system comprising:

4. 4. The robot system according to claim 1, selecting a sensor to be electrically driven from among the at least two sensors when the moving device is being moved; A robot system comprising:

5. 5. The robot system according to claim 1, selecting a sensor to be electrically driven from among the at least two sensors based on an area set based on a placement surface of the robot in the moving device and information about the robot; A robot system comprising:

6. 6. The robot system according to claim 1, selecting a sensor to be electrically driven from among the at least two sensors based on a region set based on a range of an area sensor provided on the moving device and information related to the robot; A robot system comprising:

7. 7. The robot system according to claim 5, electrically driving a sensor capable of acquiring information regarding a portion protruding from the region in the at least two sensors; A robot system comprising:

8. The robot system according to any one of claims 1 to 7, selecting a sensor to be electrically driven from among the at least two sensors based on a moving direction of the moving device; A robot system comprising:

9. 9. The robot system according to claim 1, electrically driving sensors capable of obtaining information about the load on the robot in three independent directions; A robot system comprising:

10. 10. The robot system according to claim 1, electrically driving a sensor capable of acquiring a load acting on the robot in the moving direction of the moving device; A robot system comprising:

11. The robot system according to any one of claims 1 to 10, The at least two sensors are provided on the robot, Each of the at least two sensors is capable of being independently electrically driven. A robot system comprising:

12. The robot system according to any one of claims 1 to 11, a switch for detecting when the mobile device is moving; A robot system comprising:

13. The robot system according to any one of claims 1 to 12, A motion detection device is provided on the wheels of the mobile device to detect that the mobile device is moving. A robot system comprising:

14. The robot system according to any one of claims 1 to 13, When an abnormality is detected based on the electrically driven sensor, the occurrence of the abnormality is notified to a user using at least one of a display device, an audio device, and a light-emitting device. A robot system comprising:

15. 15. The robot system according to claim 1, notifying a user that preparation for movement of the mobile device has been completed using at least one of a display device, an audio device, and a light-emitting device; A robot system comprising:

16. The robot system according to claim 15, when the selection of the sensor to be electrically driven is completed, notifying the user by using at least one of a display device and an audio device that it is OK to disconnect the power cable from the mobile device; A robot system comprising:

17. 17. The robot system according to claim 1, the robot is a robot arm, and the at least two sensors are torque sensors that obtain information about torques at joints of the robot arm; A robot system comprising:

18. A method for manufacturing an article, comprising the steps of: manufacturing an article by using the robot system according to any one of claims 1 to 17;

19. A method for controlling a robot system including a robot and a moving device capable of mounting the robot, comprising the steps of: having at least two sensors; selecting a sensor to be electrically driven from among the at least two sensors based on information about the robot; A control method comprising:

20. A mobile device capable of mounting a robot having at least two sensors, selecting a sensor to be electrically driven from among the at least two sensors based on information about the robot; A mobile device comprising:

21. A method for controlling a mobile device capable of mounting a robot having at least two sensors, comprising the steps of: selecting a sensor to be electrically driven from among the at least two sensors based on information about the robot; A control method comprising:

22. A control program capable of executing the control method according to claim 19 or 21 by a computer.

23. A computer-readable recording medium storing the control program according to claim 22.

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