Robot, robot control method, article manufacturing method using robot, control program, and recording medium

Abstract

To reduce a possibility of size increase of a robot.SOLUTION: A robot has at least two joints and the joints include a first joint and a second joint. A first drive source is provided at the first joint and a second drive source is provided at the second joint. Sizes of drive substrates which drive the first drive source and the second drive source are respectively changed. The robot is adopted.SELECTED DRAWING: Figure 6

Description

[Technical Field]

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

[0002] In recent years, robots with multiple links that operate via multiple joints have been attracting attention. Robots that operate multiple links and operate parts using end effectors located at the tips of the robots are being introduced into production factories to automate the factories. Each joint of such a robot is equipped with a drive source, such as a motor, for driving the link. Patent Document 1 describes a distributed control robot system in which a control board for individually controlling multiple drive sources and a drive board for supplying power to the drive sources are located at each joint. Distributed control reduces the concentration of load on a single control device, improving controllability. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-136454 Summary of the Invention [Problem to be solved by the invention]

[0004] In general robots, the output of the drive source tends to be greater for joints closer to the placement side (root side) of the robot, and smaller for joints closer to the tip side (hand side) of the robot. The joints on the placement side (root side) need to support multiple links and operate them collectively, while the joints on the tip side (hand side) are required to perform delicate tasks while reducing the load on the placement side (root side). However, the technology described in Patent Document 1 uses a drive board of the same size for each joint, and no consideration has been given to drive boards that are tailored to the magnitude of output of each joint in the robot. Therefore, it is conceivable that drive boards larger than necessary will be installed in the drive sources installed in the joints, which could lead to an increase in the size of the robot.

[0005] In view of the above problems, the present invention reduces the possibility of an increase in the size of a robot. [Means for solving the problem]

[0006] In order to solve the above problems, the present invention provides a robot having a first joint and a second joint, Inside the housing that makes up The first driving source a first drive board that supplies power for driving the first drive source; and a first control board that controls the power supplied from the first drive board to the first drive source. and the second joint is provided. Inside the housing that makes up The second driving source a second drive board that supplies power for driving the second drive source; and a second control board that controls the power supplied from the second drive board to the second drive source. is provided, an output from the first drive source and an output from the second drive source are different; before Record number 1 drive board The size and before Record number 2 Drive board size teeth Different Crate , The specifications including the size of the first control board and the specifications including the size of the second control board are common specifications. A robot characterized by the following was adopted. [Effects of the Invention]

[0007] According to the present invention, it is possible to reduce the possibility of an increase in the size of the robot. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram of a robot system 1000 according to an embodiment. [Figure 2]FIG. 1 is a control block diagram of a robot system 1000 according to an embodiment. [Figure 3] 2 is a diagram showing details of the control blocks of the motor control board 241 and the motor drive boards 251 to 256. FIG. [Figure 4] 2 is a diagram showing the board configuration of a motor control board 241 and motor drive boards 251 to 256 in the embodiment. FIG. [Figure 5] 3A to 3C are detailed views of the shapes of the links of the robot arm body 200 in the embodiment. [Figure 6] 10 is a diagram showing the arrangement of a motor control board 241 and motor drive boards 251, 252, and 256 in the embodiment. [Figure 7] 2 is a diagram showing the board configuration of a motor control board 241 and motor drive boards 251 to 256 in the embodiment. FIG. [Figure 8] 2 is a diagram showing the board configuration of a motor control board 241 and motor drive boards 251 to 256 in the embodiment. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

[0010] Note that the following embodiments are merely examples, and those skilled in the art can appropriately modify the detailed configurations, for example, without departing from the spirit of the present invention. Furthermore, the numerical values ​​used in the present embodiment are for reference only and do not limit the present invention. In the following drawings, the arrows X, Y, and Z indicate the coordinate system of the entire robot system. Generally, the XYZ three-dimensional coordinate system indicates the world coordinate system of the entire installation environment. Additionally, a local coordinate system may be used appropriately for the robot hand, fingers, joints, etc., depending on the convenience of control.

[0011] (First embodiment) Fig. 1 shows a schematic configuration of a robot system 1000 according to this embodiment. In Fig. 1, the robot system 1000 includes a robot arm body 200 configured as an articulated robot, a control device 300 that controls the robot arm body 200, and an external input device 400. The control device 300 includes a power supply device 350 and a robot controller (host control device) 340.

[0012] The robot arm main body 200 of this embodiment is configured with six articulated axes. The robot arm main body 200 is configured with a base 210 and six links 201 to 206. The links 201 to 206 are rotated by six drive devices 231 to 236 that rotate the respective joint axes A1 to A6 around the arrows shown in the figure. Each of the drive devices 231 to 236 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 motors provided in the drive devices 231 to 236 serve as drive sources that generate drive forces that relatively displace the respective links 201 to 206 connected to each joint. Each motor also has built-in encoders 211 to 216 that detect the rotation angle of the motor itself.

[0013] Torque sensors 221-226, which are sensors that detect force information, are provided between the output ends of the drive devices 231-236 and the links 201-206 that rotate together with the output ends. The torque sensors 221-226 each include a structure and an optical encoder that detects the relative movement of the structure. When the joints of the robot arm main body 200 are driven, the optical encoder detects the relative movement of the structures of the torque sensors 221-226 that accompanies the relative displacement of the links of the robot arm main body 200. The robot arm main body 200 also includes motor drive boards 251-256 that drive the motors of the drive devices 231-236, and a motor control board 241 that controls the motors. The motor control board 241 outputs current commands to each motor via the drive boards 251-256 based on an input torque command value, thereby controlling the operation of each motor, so that the torque detected by the torque sensors 221-226 of each joint follows the command value.

[0014] As shown in the figure, link 201 of robot arm main body 200 is connected to base 210 by drive unit 231 in the figure using a bearing (not shown) so that it can rotate together with torque sensor 221. Drive unit 231 has a movable range from the initial posture in the direction of the arrow. Link 202 of robot arm main body 200 is connected to link 201 by drive unit 232 in the figure using a bearing (not shown) so that it can rotate together with torque sensor 222. Drive unit 232 has a movable range from the initial posture in the direction of the arrow.

[0015] Link 203 of robot arm main body 200 is connected to link 202 by drive device 233 in the figure using a bearing (not shown) so that it can rotate together with torque sensor 223. Drive device 233 has a movable range in the direction of the arrow from the initial posture. Link 204 of robot arm main body 200 is connected to link 203 by drive device 234 in the figure using a bearing (not shown) so that it can rotate together with torque sensor 224. Drive device 234 has a movable range in the direction of the arrow from the initial posture.

[0016] Link 205 of robot arm main body 200 is connected to link 204 by drive device 235 in the figure using a bearing (not shown) so that it can rotate together with torque sensor 225. Drive device 235 has a movable range in the direction of the arrow from the initial posture. Link 206 of robot arm main body 200 is connected to link 205 by drive device 236 in the figure using a bearing (not shown) so that it can rotate together with torque sensor 226. Drive device 235 has a movable range in the direction of the arrow from the initial posture.

[0017] An end effector body such as an (electric) hand or a (pneumatically driven) air hand for performing assembly work or moving work on a production line is connected to the tip of the link 206 of the robot arm body 200. This end effector body is attached to the link 206, which is a predetermined part of the robot arm body 200, by (semi-)fixed means (not shown) such as screws. Alternatively, it can be attached by a detachable means (not shown) such as a latch (ratchet) fastening. In particular, if the end effector body is detachable, it is also possible to control the robot arm body 200 and attach, detach, or replace the end effector body arranged at a supply position (not shown) by the movement of the robot arm body 200 itself.

[0018] Here, in this embodiment, the tip of the robot arm main body 200 refers to the link 206 and / or the end effector main body. When the end effector main body is gripping an object, the tip of the robot arm main body 200 includes the end effector main body and the gripped object (for example, a part, tool, etc.). In other words, the link 206 and / or the end effector main body are referred to as the tip of the robot arm main body 200, regardless of whether the end effector main body is gripping an object or not.

[0019] The external input device 400 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 main body 200 or moving the tip of the robot arm main body 200. When some operation is performed on the operation unit of the external input device 400, the control device 300 transmits signals to the drive devices 231 to 236 of each joint in accordance with the operation of the external input device 400, and controls the operation of the robot arm main body 200. At this time, the control device 300 executes a robot control program including a control program described below, thereby controlling each part of the robot arm main body 200.

[0020] With the above configuration, the robot arm body 200 can move the link 206 and / or the end effector body to any position to perform a desired task. For example, by using a predetermined workpiece and another workpiece as materials and performing a process of assembling the predetermined workpiece and the other workpiece, an assembled workpiece can be produced as a final product. In this way, an article can be manufactured by the robot arm body 200.

[0021] Figure 2 is a block diagram showing a schematic configuration of the control system of the robot system 1000 of Figure 1. The control device 300 has a robot controller 340 configured as a computer, and is equipped with a CPU (Central Processing Unit) 301, which is a processor. The control device 300 also has, as storage units, a ROM (Read Only Memory) 302, a RAM (Random Access Memory) 303, an HDD (Hard Disc Drive) 304, and a recording disc drive 305. The control device 300 also has interfaces 306, 307, 308, 309, 310, and 311 for communicating with each device. The CPU 301, ROM 302, RAM 303, and interfaces 306 to 309 are connected by a bus 311 so that they can communicate with each other.

[0022] Of these, RAM 303 is used for temporary storage of data such as teaching points and control commands input by operating external input device 400. ROM 302 stores basic programs 330 such as BIOS for causing CPU 301 to execute various arithmetic processes. CPU 301 executes various arithmetic processes based on control programs recorded (stored) in HDD 304. HDD 304 is a storage unit for storing various data resulting from the arithmetic processes of CPU 301. Recording disk drive 305 can read various data, control programs, etc. recorded on a recording disk 331. Furthermore, interfaces 307 and 308 are connected to a monitor 411 for displaying various images and an external storage device 412 such as a rewritable nonvolatile memory or an external HDD.

[0023] The external input device 400 may be 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 400 can be connected to the control device 300 via wired or wireless communication means and has a user interface function for robot operation and status display. The target joint angles of each joint input by the external input device 400 are output to the CPU 301 via the interface 306 and the bus 311.

[0024] The CPU 301 receives teaching point data input, for example, by the external input device 400, from the interface 306. Furthermore, it can generate trajectories for each axis of the robot arm main body 200 based on the teaching point data input from the external input device 400 and transmit the trajectories to the driving devices 231 to 236 using the arm motor driver 230 via the interface 309. The CPU 301 outputs drive command data indicating the control amount of the rotation angle of the motor of each of the driving devices 231 to 236 to the arm motor driver 230 via the bus 311 and the interface 309 at predetermined intervals.

[0025] The motor control board 241 calculates the amount of current output to the motors of the drive devices 231-236 based on drive commands received from the CPU 301, and supplies current to each motor using the motor drive boards 251-256 to control the joint angle of each joint. The motor control board 241 also outputs detection signals from the encoders 211-216 and torque sensors 221-226 to the CPU 301 via the interface 309 and bus 311. That is, the CPU 301 executes feedback control of the motors of the drive devices 231-236 via the motor control board 241 so that the current joint angle values ​​of the joints detected by the encoders 211-216 become the target joint angles. Similarly, the CPU 301 executes feedback control of the motors so that the current torque values ​​of the joints detected by the torque sensors 221-226 become the target torques.

[0026] Furthermore, by returning the outputs of the torque sensors 221-226 to the control device 300 and feeding them back into the driving of the respective driving devices 231-236, it is possible to control the torque applied to each of the links 201-206 during driving. Furthermore, the force generated in the link 206 of the robot arm main body 200 can be obtained by calculation from the values ​​of the respective torque sensors 221-226, making it possible to feedback control the load applied to the parts to be assembled.

[0027] When a robot hand body is used as the end effector body (not shown), the control device 300 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 drive commands received from CPU 301, supplies current to the hand motor, and controls the speed of the hand motor. The hand motor driver also outputs a pulse signal from the hand motor's encoder to CPU 301 via the interface and bus. That is, CPU 301 performs 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.

[0028] FIG. 3 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. 3, the motor control board 241 and the corresponding motor drive boards 251-256 are collectively shown as a single block, and the components provided on the motor control board 241 and the components provided on each of the motor drive boards 251-256 will be described later using FIG. 4. The ratio of the number of motor control boards 241 to the number of drive boards 251-256 is 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 depending on the electrical output of the motor of each joint. The motor control board 241 is equipped with a communication driver 103 and a control circuit 105. The motor drive boards 251-256 are equipped with a power supply circuit 104, an inverter 106, a power connector 119, and a communication connector 120. The motor drive boards 251 to 256 and the motor control board 241 are electrically connected by, for example, an inter-board connector, a cable, a flexible flat cable, or the like.

[0029] The robot controller 340 is daisy-chained to each motor control board 241 via the serial communication line 130. The robot controller 340 performs distributed control, controlling each motor of each drive device 231 to 236 by sending commands to the motor control board 241. The robot controller 340 calculates the trajectory of the robot arm main body 200 to realize operations taught by the external input device 400. The robot controller 340 sends various commands to each motor control board 241, such as operation commands (specifically, position commands) that instruct the operation of each rotary motor based on the results of the trajectory calculation, operation execution start commands that instruct the start of execution of operations based on the operation commands, and synchronization commands.

[0030] The power supply device 350 supplies power to each motor control board 241 and each motor drive board 251-256 (motor drive boards 253-255 are not shown because they are omitted) via the power cable 140. The motor drive boards 251-256 to which power has been supplied supply power to each motor of the drive devices 231-236 based on instructions from the motor control board 241, thereby driving the motor.

[0031] Each motor control board 241 and motor drive board 251-256 is connected to the robot 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 via the serial communication line 130 using a communication protocol such as CAN. In addition, status notifications and the like are transmitted and received between the robot controller 340 and each motor control board 241 via the serial communication line 130.

[0032] Each motor control board 241 is equipped with a communication driver 103 that receives signals indicating various commands from the robot controller 340, and the motor drive boards 251 to 256 are equipped with a power supply circuit 104 that converts the voltage applied by the power supply device 350 into a predetermined DC voltage. They are connected to the power supply device 350 by a power cable 140 and a power connector 119. The power connector 119 functions as a power supply IF.

[0033] The control circuit 105 of each motor control board 241 is composed of a microcomputer and has multiple switching elements. The control circuit 105 has an arithmetic unit 111, a communication control unit 112, a memory 113, a clock generation unit 114, a timer 115, a PWM waveform generation unit 116, 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.

[0034] The drive device 231 also includes a current detection unit 107 that detects the current flowing from the inverter 106 to the motor (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.

[0035] Furthermore, the counter 118 acquires the detection result of the encoder 211, which detects the rotational position of the motor of the driving device 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 as the rotor rotates. The counter 118 counts the number of pulses output by the encoder 211. The counter 118 then 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. For the sake of simplicity of explanation, it is also assumed that a separate counter is provided to acquire the detection result of the torque sensor 221, although this is not shown in FIG. 3.

[0036] The communication control unit 112 controls the 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.

[0037] 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 robot controller 340, current information indicating the current detection results, and position information indicating the position detection results. As part of its calculation processing, the calculation unit 111 calculates a drive command to be output to the PWM waveform generation unit 116. Then, when the calculation of this drive command is completed, the calculation unit 111 outputs the drive command to the PWM waveform generation unit 116.

[0038] The PWM waveform generation 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 the switching elements using the PWM signal, and outputs the modulated voltage to the motor of the drive device 231. As a result, an AC current, for example, a three-phase AC current, is output to the motor of the drive device 231. Through the above-described operations of the PWM waveform generation unit 116 and the inverter 106, the motor of the drive device 231 is driven in accordance with the received drive command. In other words, the PWM waveform generation unit 116 and the inverter 106 supply a current to the motor of the drive device 231 in accordance with the received drive command.

[0039] 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 a digital signal to the calculation unit 111. The calculation unit 111 monitors the behavior of the robot arm main body 200, that is, the rotational position and current of the motor of the drive device 231, and performs feedback control based on commands received from the robot controller 340 to control the driving of the motor of the drive device 231. Specifically, the calculation unit 111 executes calculation processing to calculate drive commands that control the position, speed, and current (torque) of the motor through position, speed, and current control processing, based on the current information from the current detection unit 107 and position information acquired by the encoder 211.

[0040] FIG. 4 is a diagram showing the board configuration of the motor control board 241 and motor drive boards 251 to 256 in this embodiment. For ease of explanation, FIG. 4 shows the motor drive board 251 as an example. It is assumed that the other motor drive boards are also connected to the motor control board 241 as described below. FIG. 4(a) is a perspective view of the motor drive board 251. FIG. 4(b) is a perspective view of the motor control board 241. FIG. 4(c) is a perspective view of the motor drive board 251 and the control board 241 combined to form a pair of boards, one above the other.

[0041] As shown in FIG. 4(a), the motor drive board 251 includes an inverter 106, a power supply circuit 104, a power connector 119, a communication connector 120, a motor drive power connector 121, and an inter-board connector 122. The power connector 119 and the communication connector 120 are electrically connected to the robot controller (host control device) 340, the power supply device 350, or each board of another joint via a power cable 140 and a serial communication line 130. The motor drive power connector 121 is connected to the motor of the drive device 231 via a cable and supplies the motor drive power output from the inverter 106. Note that, although the power connector 119 and the communication connector 120 are configured as separate bodies in FIG. 4(a) of this embodiment, they may be configured as the same connector.

[0042] As shown in Figure 4(b), the motor control board 241 includes a communication driver 103, a control circuit 105 configured with a microcomputer, a position detection connector 123, and an inter-board connector 122. In Figure 4(b), the inter-board connector 122 is provided on the back side of the motor control board 241. The position detection connector 123 is electrically connected to an encoder 211 arranged on the motor of the drive device 231. In this embodiment, the communication connector 120 may be referred to as the first connector, the power connector 119 as the second connector, the motor drive power connector 121 as the third connector, and the position detection connector 123 as the fourth connector.

[0043] As shown in FIG. 4(c), the motor drive board 251 and the motor control board 241 are electrically connected via the board-to-board connector 122, and the motor drive board 251 and the motor control board 241 are connected to supply drive power to each electronic component and to communicate various commands (control signals). Four metal spacers (supports) 124 are placed between the motor drive board 251 and the motor control board 241. partThis increases the contact area between the GNDs of both boards and reduces impedance, thereby achieving the effect of strengthening noise resistance. In addition, the use of metal spacers 124 (with high thermal conductivity) makes it possible to dissipate heat generated in the motor drive board 251 when the motor of the drive device 231 is driven. This makes it possible to reduce the heat dissipation pattern (solid GND) on the motor drive board 251, thereby enabling the motor drive board 251 to be made more compact.

[0044] 4(c), the motor control board 241 is arranged on the motor drive board 251 so as to cover the power supply circuit 104 and inverter 106 of the motor drive board 251 and to allow access to each connector of the motor drive board. As a result, when the motor control board 241 and the motor drive board 251 are provided in the robot arm main body 200, if the user is required to access each board for maintenance or the like, parts that pose a risk of electric shock, such as the power supply circuit 104 and inverter 106, can be made difficult to access. Also, each connector on the motor drive board 251 that requires the user to plug and unplug cables can be made easily accessible. As a result, user safety can be ensured during maintenance, while convenience during maintenance can also be ensured.

[0045] 4, the position detection connector 123 is provided on the motor control board 241, but there is no problem if it is provided on the motor drive board 251. By providing it on the motor drive board 251, it becomes possible to change the arrangement of each connector for each joint, and it becomes possible to wire each cable via the shortest route and to design an optimal wiring route at each joint of the robot arm main body 200. This makes it possible to reduce the overall size of the robot arm main body 200. Furthermore, the motor drive board may be mounted with electrical components that are individually optimized according to the motor specifications and operating current, or conversely, all of the joints may be configured with the same electrical components.

[0046] Next, the board design of the motor drive board is changed in accordance with the operating current of each motor arranged in each of the drive devices 231 to 236 of the robot arm main body 200, and the arrangement of the motor drive board on the robot arm main body 200 will be described in detail. FIG. 5 is a detailed diagram of the shape of each link of the robot arm main body 200 in this embodiment. As shown in the figure, link 201 of the robot arm main body 200 rotates relative to the base 210 around axis A1 as a rotation axis. Link 202 of the robot arm main body 200 rotates relative to link 201 around axis A2 as a rotation axis. Link 203 of the robot arm main body 200 rotates relative to link 202 around axis A3 as a rotation axis. The drive device 233 has a movable range in the direction of the arrow from the initial posture. Link 204 of the robot arm main body 200 rotates relative to link 203 around axis A4 as a rotation axis. Link 205 of the robot arm main body 200 rotates relative to link 204 around axis A5 as a rotation axis. The link 206 of the robot arm body 200 rotates relative to the link 205 about an axis A6.

[0047] The drive device, motor drive board, motor control board, etc. provided inside the robot arm main body 200 are the same as those described above. In this embodiment, the joint that enables the base 210 and link 201 to rotate, and the motor may be referred to as a first joint and a first drive source. The joint that enables the links 205 and 206 to rotate, and the motor may be referred to as a second joint and a second drive source. The joint that enables the links 201 and 202 to rotate, and the motor may be referred to as a third joint and a third drive source.

[0048] Figure 6 is a diagram showing the arrangement of motor control board 241 and motor drive boards 251, 252, and 256 in this embodiment. Figure 6(a) is a diagram showing the arrangement of motor control board 241 and motor drive board 251 on base 210. Figure 6(b) is a diagram showing the arrangement of motor control board 241 and motor drive board 252 on link 202. Figure 6(c) is a diagram showing the arrangement of motor control board 241 and motor drive board 256 on link 205. Note that, for simplicity of explanation, motor drive boards 251, 252, and 256 will be used as examples for explanation, and motor drive boards 253, 254, and 255 will be assumed to be designed to have the same size as motor drive board 252.

[0049] As shown in FIG. 6( a), the motor drive board 251 provided on the base 210 drives the motor of the drive device 231 that operates the link 201 on the base side of the robot arm main body 200, and therefore requires a large operating current. Therefore, the motor drive board 251 is the largest in size compared to the other motor drive boards. As shown in FIG. 6( b), the motor drive board 252 provided on the link 202 drives the motor of the drive device 232 that operates the link 202, which is the intermediate part of the robot arm main body 200. Therefore, the size of the motor drive board 252 is slightly smaller than that of the motor drive board 251. As shown in FIG. 6( c), the motor drive board 256 provided on the link 205 drives the motor of the drive device 236 that operates the link 206 on the tip side of the robot arm main body 200, and therefore requires a small operating current. Therefore, the motor drive board 256 is the smallest in size compared to the other motor drive boards.

[0050] According to the present embodiment, the motor drive boards 251-256 can be designed with board sizes optimal for each joint depending on the operating current of each motor of each drive device 231-236. Because such motor drive boards are arranged near the motors that move each joint, taking into account the effects of noise, the arrangement space may be narrow due to the configuration of the robot arm, and the board size (area) may be severely limited. However, by designing boards with board sizes optimal for each joint depending on the operating current of each motor, as in the present embodiment, it is possible to overcome the limitations imposed by the configuration of the robot arm and also reduce the board size. This reduces the possibility of an increase in the size of the robot.

[0051] In this embodiment, the motor control board that controls the motor and the drive board that drives the motor are separate. In a distributed control type, the board for each joint is equipped with a motor drive unit, a control unit that controls the motor drive unit, a power supply circuit, a robot controller (host control device), and a communication interface with the boards for each joint, and so on, and the boards have many electrical components, which increases the board's footprint. However, by separating the motor control board that controls the motor and the drive board that drives the motor as in this embodiment, it is possible to arrange the boards above and below each other as shown in Figure 4(c), thereby reducing the board's footprint.

[0052] Furthermore, by mounting the power supply circuit 104 on the motor drive boards 251-256, they can be individually optimized to the specifications of the motors and inverters 106 of the drive units 231-236, making it possible to standardize the motor control board 241 for all joints. By standardizing the motor control board 241, the cost of manufacturing the motor control board 241 decreases, thereby reducing the cost of the robot arm main body 200. Furthermore, even when developing robot arms with different uses (for example, different work targets or weights of transported items, or a need for faster production speed), it is possible to reuse the motor control board simply by revising the motor drive board to suit the use. This also reduces development time and costs.

[0053] Generally, when the motor load decreases, the operating current also decreases, allowing the width of the power supply pattern to be designed narrower. Furthermore, the amount of heat dissipated from the electronic components of the power supply circuit and inverter also decreases, allowing the heat dissipation pattern to be smaller, and when the motor load decreases, the area of ​​the motor drive board can be made smaller. Furthermore, by mounting the inverter on the motor drive board, noise generated during motor operation can be reduced. Furthermore, by separating the heat generated by the operating current from the motor control board, it is possible to reduce the number of noise filters in the signal system and reduce the area of ​​the heat dissipation pattern of the motor control board 241, thereby making it possible to miniaturize the motor control board.

[0054] In a vertically articulated robot such as the robot arm main body 200 of this embodiment, the force of bending and extending in a direction perpendicular to the arm placement surface is affected by gravitational acceleration during an arm lifting operation, and is therefore greater than the load of rotating in a horizontal direction. For this reason, drive boards may be designed in two sizes, one for joints that rotate in the horizontal direction and one for joints that bend and extend in the vertical direction. This can be achieved by using a larger drive board for the joint that bends and extends in the vertical direction and a smaller drive board for the joint that rotates in the horizontal direction.

[0055] Furthermore, the size of the motor drive board may be gradually reduced toward the hand end, with the board area being divided into different sizes for each joint of the robot arm main body. In this case, the size of the motor drive board at the hand end (tip) of the robot arm main body 200 will be smaller than the sizes of all the motor drive boards at the other joints. In particular, in the case of a horizontal articulated robot (SCARA robot), the weight (= motor load) decreases toward the hand end, so it is effective to design the area of ​​the drive board located on the hand end to be gradually smaller.

[0056] In this embodiment, the size of the motor drive board is considered based on the area, but it may also be considered based on the volume, weight, or mass. At least one of the area, volume, weight, and mass of the motor drive board may be changed depending on the electrical output of the motor to be controlled.

[0057] (Second embodiment) Next, the second embodiment will be described in detail. Below, the hardware and control system configurations that are different from those of the first embodiment will be illustrated and described. Furthermore, it is assumed that the same configurations and operations as those of the first embodiment can be achieved, and detailed descriptions thereof will be omitted.

[0058] 7 is a diagram showing details of the control blocks of the motor control board 241 and motor drive boards 251-256 in this embodiment. In this embodiment, the robot controller (host control device) 340 and the motor drive boards 251-256 are electrically connected via a serial communication line 130. The power supply device 350 and the motor drive boards 251-256 are also connected so that power is supplied via a power cable 140. Furthermore, the encoders 211-216 are electrically connected to the motor drive boards 251-256, respectively, and then communicate with the control circuit 105 of each motor control board 241 via a position detection connector 123.

[0059] According to the present embodiment, the power cable 140, the serial communication line 130, and the position detection connectors 123 of the encoders 211-216 are mounted on the drive boards 251-256. This allows board design and component mounting to be optimized individually for each joint, making it possible to advantageously design the wiring inside the housing of the robot arm main body 200. Furthermore, the power lines, communication lines, and encoder interfaces of the motor control board 241 and the motor drive boards 251-256 can be aggregated in one location, which is expected to have the effect of reducing the size of the motor control board 241. Note that this embodiment and its modified examples may be combined with the above-mentioned embodiments and modified examples in a given robot.

[0060] (Third embodiment) Next, the third embodiment will be described in detail. Below, the hardware and control system configurations that are different from those of the first and second embodiments will be illustrated and described. Furthermore, it is assumed that the same configurations and operations as those of the first and second embodiments can be achieved, and detailed descriptions thereof will be omitted.

[0061] 8 is a diagram showing details of the control blocks of the motor control board 241 and the motor drive boards 251 to 255 in this embodiment. In this embodiment, the control device 300 and each motor control board 241 are electrically connected via the power cable 140 and the serial communication line 130. Also, the motor drive board 251 is mounted with inverters 106 and current detection units 107 for two axes, and the major difference is that only the motor drive board 251 controls the motors for two axes of the drive devices 231 and 232.

[0062] Generally, due to the design characteristics of a robot arm, there is more space for arranging boards on the base side than on the hand side, so board sizes can be made larger. By configuring the ratio of the number of motor control boards to motor drive boards on the base side at 2:1, the entire robot arm main body 200 can be made even smaller. While this embodiment uses the drive devices 231 and 232 on the base side as an example, this configuration is not limited to this. That is, a configuration in which the number of motor control boards to motor drive boards is arranged at a ratio of 2:1 at any location of each joint is also acceptable. This embodiment and its modifications may be implemented in combination with the above-described embodiments and modifications in a given robot.

[0063] (Other embodiments) The processing procedures of the above-described embodiments are specifically executed by the CPU 301 of the control device 300. Therefore, it is also possible to configure the system to read and execute a software program capable of executing the above-described functions from a recording medium. In this case, the program read from the recording medium itself will realize 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.

[0064] In each embodiment, the computer-readable recording medium is a ROM, a RAM, or a flash ROM, and the program is stored in the ROM, RAM, or flash ROM. However, the present invention is not limited to this configuration. The program for implementing the present invention may be recorded on any computer-readable recording medium. For example, a hard disk drive (HDD), an external storage device, a recording disk, etc. may be used as a recording medium for supplying the control program.

[0065] In addition, in the various embodiments described above, the robot arm main body 200 has been described as using a multi-joint robot arm having multiple joints, but the number of joints is not limited to this. While a vertical multi-axis configuration has been shown as the type of robot arm, the same configuration as above can also be implemented with different types of joints, such as a horizontal multi-joint type, a parallel link type, or an orthogonal robot. Furthermore, the present invention may be applied to prosthetic limbs and powered suits (power-assisted suits) equipped with sensors that detect force, such as torque sensors.

[0066] Furthermore, the various embodiments described above can be applied to machines that can automatically perform movements such as extension and contraction, bending and stretching, up and down movement, left and right movement, or rotation, or a combination of these movements, based on information stored in a memory device provided in the control device.

[0067] The present invention is not limited to the above-described embodiments, and many modifications are possible within the technical concept of the present invention. Furthermore, 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. [Explanation of symbols]

[0068] 103 Communication Driver 104 Power supply circuit 105 Control circuit 106 Inverter 119 Power Connector 120 Communication Connector 121 Motor drive power connector 122 Board-to-board connector 123 Position detection connector 124 Spacer (support) 130 serial communication line 140 Power Cable 200 Robot arm body 201, 202, 203, 204, 205, 206 Links 210 Foundation 211, 212, 213, 214, 215, 216 Encoders 221, 222, 223, 224, 225, 226 Torque sensors 231, 232, 233, 234, 235, 236 Drive unit 241 Motor control board 251, 252, 253, 254, 255, 256 Motor drive board 300 control device 340 Robot Controller 350 power supply 400 External Input Device

Claims

1. A robot having a first joint and a second joint, a first drive source, a first drive board that supplies power for driving the first drive source, and a first control board that controls the power supplied from the first drive board to the first drive source are provided inside a housing that configures the first joint; a second drive source, a second drive board that supplies power for driving the second drive source, and a second control board that controls the power supplied from the second drive board to the second drive source are provided inside a housing that configures the second joint; an output from the first drive source and an output from the second drive source are different from each other; The first drive substrate and the second drive substrate have different sizes, The specifications including the size of the first control board and the specifications including the size of the second control board are common specifications. A robot characterized by:

2. The robot according to claim 1, The first drive substrate and the second drive substrate have different sizes corresponding to the outputs of the first drive source and the second drive source, respectively. A robot characterized by:

3. 3. The robot according to claim 1, When the output from the first drive source is larger than the output from the second drive source, the first drive substrate is larger than the second drive substrate. A robot characterized by:

4. The robot according to any one of claims 1 to 3, When the electrical output of the first driving source is the largest and the output of the second driving source is the smallest, the first driving substrate is the largest and the second driving substrate is the smallest. A robot characterized by:

5. The robot according to claim 1, It has a third joint, a third drive source and a third drive substrate that drives the third drive source are provided inside a housing of the third joint, When the output of the third driving source is smaller than the output of the first driving source and larger than the output of the second driving source, the third driving substrate is smaller than the first driving substrate and larger than the second driving substrate. A robot characterized by:

6. The robot according to claim 1, It has a third joint, a third drive source is provided inside a housing of the third joint, The first drive substrate also drives the third drive source. A robot characterized by:

7. The robot according to claim 5, a plurality of other joints different from the first joint, the second joint, the third joint, the first joint, the second joint, and the third joint; a drive source is provided inside each of the housings of the other joints, The drive sources inside the housings of the other joints are each driven by the third drive board. A robot characterized by:

8. The robot according to claim 5, a plurality of other joints different from the first joint, the second joint, the third joint, the first joint, the second joint, and the third joint; a drive source and a drive circuit board are provided inside the housing of each of the other joints, The first drive substrate, the second drive substrate, the third drive substrate, and the respective drive substrates that drive the drive sources of the other joints are changed in size. A robot characterized by:

9. The robot according to claim 8, a base that is the base of the robot and a predetermined portion that is the tip of the robot; The sizes of the first drive substrate, the second drive substrate, the third drive substrate, and the respective drive substrates that drive the drive sources of the other joints become smaller as the locations where they are arranged move from the base toward the predetermined portion. A robot characterized by:

10. The robot according to any one of claims 1 to 9, The first drive board and the first control board are arranged vertically to form a pair, The second drive board and the second control board are arranged vertically to form a pair. A robot characterized by:

11. The robot according to claim 10, The first drive board and the first control board are arranged vertically by metal supports, The second drive board and the second control board are arranged vertically by metal supports. A robot characterized by:

12. The robot according to claim 11, The support pillars are arranged at four locations on the first drive board, the second drive board, the first control board, and the second control board. A robot characterized by:

13. The robot according to any one of claims 1 to 12, Each drive board is equipped with a power supply circuit and an inverter. A robot characterized by:

14. The robot according to any one of claims 1 to 13, Each drive board is provided with a first connector for communication, a second connector for connection to a power source, and a third connector for supplying power to the target. A robot characterized by:

15. The robot according to any one of claims 1 to 14, The control board provided on each drive board is provided on the drive board so as to cover the power supply circuit and the inverter. A robot characterized by:

16. The robot according to claim 14, The control boards provided on the respective drive boards are provided on the drive boards so as not to cover the first connector, the second connector, and the third connector. A robot characterized by:

17. The robot according to any one of claims 1 to 16 is a vertical articulated robot or a horizontal articulated robot. A robot characterized by:

18. 18. The robot according to claim 1, The size of the first drive substrate and the size of the second drive substrate are made different based on at least one of the area, volume, weight, or mass of the first drive substrate and the second drive substrate. A robot characterized by:

19. 19. The robot according to claim 1, The first control board and the second control board are mutually interchangeable. A robot characterized by:

20. 20. A method of using the robot according to any one of claims 1 to 19, characterized in that the robot is used to manufacture an article.

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