Sensor system

Abstract

A sensor system includes a sensor capable of detecting an object contained in a fan-shaped detection region, and comprises: a sensor for outputting the relative position of an object present in the detection region as a polar coordinate value of a polar coordinate system having the sensor as the origin; an input unit with which it is possible to input conditions of a detection range for detecting the object in the detection region; and a setting unit for setting the detection range of the sensor as straight boundary lines on the basis of the input conditions of the detection range.

Description

Sensor System

[0001] A sensor system is disclosed herein.

[0002] Conventionally, radar devices have been known that can set a line-of-sight area in which targets are detected and a non-line-of-sight area in which targets are not detected within a detection area. For example, Patent Document 1 discloses a radar device that sets a sector-shaped line-of-sight area and also sets an arc-shaped non-line-of-sight area (a shape obtained by removing a smaller sector-shaped line-of-sight area from the sector-shaped detection area).

[0003] Japanese Patent Application Laid-Open No. 2017-44567

[0004] However, since the above-mentioned radar device sets an arc-shaped non-line-of-sight area, there is a risk that the non-line-of-sight area will be set excessively if there are linear obstructions to the detection area, such as walls or pillars.

[0005] A main object of the present disclosure is to enable the detection range to be set in an appropriate range.

[0006] The present disclosure has adopted the following means to achieve the above-mentioned main object.

[0007] The sensor system of the present disclosure is a sensor stem including a sensor capable of detecting an object contained in a fan-shaped detection area, the sensor outputting the relative position of the object present in the detection area as a polar coordinate value in a polar coordinate system with the sensor as the origin, an input unit capable of inputting conditions for a detection range for detecting an object in the detection area, and a setting unit that sets the detection range of the sensor as a straight boundary line based on the input conditions for the detection range.

[0008] In the sensor system of the present disclosure, the boundary lines of the detection range can be set as straight lines, so the detection range can be set just right.

[0009] 1 is a schematic configuration diagram of a robot system 1. FIG. 2 is a block diagram showing electrical connection relationships of the robot system 1. FIG. 3 is a flowchart showing an example of a detection range setting process. FIG. 4 is an explanatory diagram showing the relationship between polar coordinate values ​​and Cartesian coordinate values ​​of a detection point. FIG. 5 is an explanatory diagram showing an example of a setting screen Sc before the detection range A is changed. FIG. 6 is an explanatory diagram showing an example of a setting screen Sc after the detection range A is changed. FIG. 7 is a flowchart showing an example of a detection process. FIG. 8 is a flowchart showing a modified example of the detection range setting process. FIG. 9 is an explanatory diagram when converting the boundary line of the Cartesian coordinate system of the detection range A into a polar coordinate system. FIG. 10 is a flowchart showing a modified example of the detection process. FIG. 11 is a schematic configuration diagram showing a modified example of the robot system.

[0010] Next, embodiments of the present disclosure will be described with reference to the drawings.

[0011] Fig. 1 is a schematic configuration diagram of a robot system 1. Fig. 2 is a block diagram showing the electrical connections of the robot system 1. As shown in the figure, the robot system 1 of this embodiment includes a robot main body 10, a robot control device 20 that controls the operation of the robot main body 10, a robot safety device 30 that can detect objects (interfering objects such as a worker) around the robot main body 10, and a setting device 40 (see Fig. 2).

[0012] The robot body 10 is a work robot that performs a specified task, and examples thereof include a processing robot that processes a workpiece with a tool, a transport robot that grasps a workpiece with a chuck and transports it to another position, and an assembly robot that grasps a workpiece with a chuck and assembles it to an object.

[0013] As shown in Fig. 1, the robot main body 10 has a base 11 and an articulated arm 12 mounted on the base 11. The articulated arm 12 has a plurality of arms connected in series to the base 11 via joint axes. As shown in Fig. 2, each joint axis is provided with a servo motor 15 that drives the corresponding joint axis, and an encoder 16 (rotary encoder) that detects the rotation angle of the corresponding servo motor 15. The robot main body 10 also has an amplifier unit 17 that applies a driving current to each servo motor 15.

[0014] The robot control device 20 includes a control unit 21 configured as a microprocessor including a CPU, ROM, and RAM, and an I / O port 22 for exchanging signals with the control unit 31 of the safety device 30. The robot control device 20 also outputs control signals to the amplifier unit 17 of the robot main body 10 and inputs detection signals from the encoder 16.

[0015] The control unit 21 of the robot control device 20 controls the operation of the robot main body 10 as follows. Specifically, the control unit 21 first sets a target angle for each joint axis of the articulated arm 12 using inverse kinematics based on the target position and target posture of the hand. Next, the control unit 21 acquires the current angle of each joint axis from the corresponding encoder 16 and sets a speed command value for each joint axis using feedback calculations (e.g., proportional-integral calculations or proportional-integral-derivative calculations) based on the difference between the target angle and the current angle. Next, the control unit 21 inputs a speed limit value (described later) from the safety device 30. The control unit 21 then multiplies the speed command value according to the speed limit value to set a target speed. The speed limit value is set, for example, so that the robot speed is more significantly limited as the distance of an object detected by the safety device 30 decreases, i.e., as the object approaches the robot main body 10. For example, if the speed limit value is 1, the target speed is the same as the speed command value. In other words, the operation of the robot main body 10 is not limited. Furthermore, if the speed limit value is 0.5, the target speed is half the speed command value. Furthermore, if the speed limit value is 0, the target speed will be 0 regardless of the speed command value. In other words, the operation of the robot body 10 is stopped.

[0016] Once the target speed is set, the control unit 21 calculates the current speed from the current angle of the joint axis obtained from the encoder 16, and sets a torque command value to be output from the servo motor 15 by feedback calculation (for example, proportional-integral calculation or proportional-integral-derivative calculation) based on the difference between the calculated current speed and the target speed. Then, the control unit 21 outputs a control signal to the corresponding amplifier unit 17 so that the servo motor 15 outputs a torque corresponding to the set torque command.

[0017] In this embodiment, the robot safety device 30 is attached to the hand of the articulated arm 12. The safety device 30 includes a control unit 31 configured as a microprocessor including a CPU, ROM, and RAM, a sensor unit 32 that monitors the surroundings, and an I / O port 33 for exchanging signals with the control unit 21 of the robot control device 20. Note that the signals exchanged with the control unit 21 of the robot control device 20 may be duplicated.

[0018] In this embodiment, the sensor unit 32 is configured as an FMCW (Frequency Modulation Continuous Wave) radar sensor. The sensor unit 32 has, for example, a fan-shaped detection area in three-dimensional space. The sensor unit 32 includes a transmitting antenna that transmits a transmitted chirp, a receiving antenna that receives a reflected wave from an object as a received chirp, a mixer that mixes the transmitted chirp and the received chirp to generate an intermediate frequency signal (IF signal), and a processing unit that processes the IF signal to detect the relative distance to the object, the relative velocity to the object, and the angle of the object. The transmitting antenna transmits multiple transmitted chirps, each spaced at a fixed interval, as one frame. The processing unit includes an A / D converter that performs A / D conversion on the IF signal generated by the mixer, a DSP that performs Fourier transform processing (FFT processing) on ​​the A / D converted IF signal, and the like. The DSP performs FFT processing (distance FFT processing) on ​​the IF signal in chirp units to obtain a frequency spectrum, and calculates the relative distance between the sensor unit 32 and an object based on the peak frequency.The DSP also performs further FFT processing (velocity FFT processing) on ​​the data after the distance FFT processing in frame units to obtain a frequency spectrum, and calculates the relative velocity between the sensor unit 32 and an object based on the peak frequency.The DSP also performs FFT processing (angle FFT processing) on ​​the data after the velocity FFT processing in receiving antenna units to obtain a frequency spectrum, and calculates the angle of the object relative to the sensor unit 32 based on the peak frequency.

[0019] The setting device 40 is a device that pre-sets the boundaries of a detection range A, which is a range within the detection area of ​​the sensor unit 32 of the safety device 30 within which the detection results are effectively handled. The setting device 40 is not normally connected to the safety device 30, but is connected to the safety device 30 via a cable when setting the detection range A. The setting device 40 is configured as a computer including a CPU 41, a ROM 42, a RAM 43, a storage (e.g., an SSD or HDD) 44, and an I / O port 45 for exchanging signals with the control unit 31 of the safety device 30. A dedicated application used to set the detection range A is installed in the storage 44. An input device 46 such as a mouse or keyboard and a display device 47 such as a liquid crystal display or an organic EL display are connected to the setting device 40. The setting device 40 inputs operation signals from the input device 46 and outputs image signals to the display device 47.

[0020] Next, the operation of the robot system 1 will be described. First, the operation of the setting device 40 will be described. Fig. 3 is a flowchart showing an example of a detection range setting process executed by the CPU 41 of the setting device 40. The detection range setting process is a process for setting the boundary line of the detection range A within the detection range of the sensor unit 32 prior to the operation of the robot control device 20. The detection range setting process is started when an application for setting the detection range is launched while the setting device 40 is connected to the safety device 30.

[0021] When the detection range setting process begins, the CPU 41 first displays a setting screen Sc on the display device 47 (S100). The setting screen Sc includes a setting condition input field C1 for inputting setting conditions for the detection range A and a detection range display field C2 for displaying the detection range A and its boundary line. The boundary line in the detection range display field C2 is displayed in a Cartesian coordinate system. Here, the Cartesian coordinate system is a three-dimensional coordinate system with a predetermined point on the safety device 30 as the origin, the left-right direction as the X-axis, the front-rear (back) direction as the Y-axis, and the up-down direction as the Z-axis. In the initial state, the detection range A coincides with the detection area (the range in which radio waves can be transmitted and received) of the sensor unit 32. The operator can arbitrarily set the detection range A by specifying a boundary line on the setting screen Sc with a straight line. The boundary lines of the Cartesian coordinate system include a front boundary line D1 and a back boundary line D2 parallel to the X-axis. The boundary lines of the Cartesian coordinate system also include a left boundary line E1 and a right boundary line E2 parallel to the Y-axis. The front boundary line D1 and the back boundary line D2 are given as Y-axis coordinate values ​​as shown in the following equations (1) and (2), and the left boundary line E1 and the right boundary line E2 are given as X-axis coordinate values ​​as shown in the following equations (3) and (4).

[0022] Y=D1...(1) Y=D2...(2) X=E1...(3) X=E2...(4)

[0023] The operator can set the detection range A by specifying the boundary lines using values ​​in a polar coordinate system on the setting screen Sc. The polar coordinate system is a three-dimensional coordinate system with a predetermined point on the safety device 30 as its origin. The values ​​in the polar coordinate system include a left angle boundary α1 and a right angle boundary α2 in the horizontal direction, a lower angle boundary β1 and an upper angle boundary β2 in the vertical direction, and a near distance boundary R1 and a far distance boundary R2 in the front-to-rear (rear) direction. The left angle boundary α1 and the right angle boundary α2 in the horizontal direction are angles between the Y axis and the boundary lines determined based on the left angle boundary α1 and the right angle boundary α2, respectively, when the detection range A is viewed in the XY plane. The lower angle boundary β1 and the upper angle boundary β2 are angles between the Y axis and the boundary lines determined based on the lower angle boundary β1 and the upper angle boundary β2, respectively, when the detection range A is viewed in the YZ plane. The near distance boundary R1 and the far distance boundary R2 are the shortest and longest distances that can be detected in the detection range A. The boundaries of the polar coordinate system are converted into an orthogonal coordinate system and displayed on the XY planar image Im1 and the YZ planar image Im2. The boundaries of the polar coordinate system include a left angle boundary line F1 and a right angle boundary line F2 expressed by the following equations (5) and (6). The boundaries of the polar coordinate system also include a lower angle boundary line G1 and an upper angle boundary line G2 expressed by the following equations (7) and (8). The boundaries of the polar coordinate system also include a near distance boundary line H1 and a far distance boundary line H2 expressed by the following equations (9) and (10).

[0024] Y=tan(π / 2-α1)・X...(5) Y=tan(π / 2-α2)・X...(6) Z=tan(β1)・Y...(7) Z=tan(β2)・Y...(8) √(X^2+Y^2+Z^2)=R1...(9) √(X^2+Y^2+Z^2)=R2...(10)

[0025] The setting condition input field C1 includes a front / rear (back) boundary line input section 50, a left / right boundary line input section 60, a distance boundary line input section 70, a horizontal angle boundary line input section 80, and a vertical angle boundary line input section 90. Each input section is provided with a slide bar B and sliders S1 and S2 that can be moved left and right by an operator's operation. Furthermore, by moving the corresponding slider S1 on the slide bar B, the position of the front boundary line D1, the position of the left boundary line E1, the close distance boundary R1, the left angle boundary α1, and the lower angle boundary β1 are specified. Furthermore, by moving the corresponding slider S2 on the slide bar B, the position of the back boundary line D2, the position of the right boundary line E2, the far distance boundary R2, the right angle boundary α2, and the upper angle boundary β2 are specified. Each input section includes a display input field Q1 that displays the position of the slider S1 as a numerical value and allows the numerical value to be input by operating the input device 46 such as a keyboard, and a display input field Q2 that displays the position of the slider S2 as a numerical value and allows the numerical value to be input by operating the input device 46 such as a keyboard. In addition, the input screen Sc2 also includes a save button that is selected when the operator has completed setting the detection range A, and a cancel change button that is selected when the operator cancels the changes to the detection range A and returns the detection range A to its initial state.

[0026] The detection range display field C2 also includes an XY planar view image Im1 that displays the detection range A when viewed in the XY plane, and a YZ planar view image Im2 that displays the detection range A when viewed in the YZ plane. Here, the detection range A when viewed in the XY plane is the range where the detection region of the sensor unit 32 overlaps with the range surrounded by the front boundary line D1, the rear boundary line D2, the left boundary line E1, the right boundary line E2, the left angle boundary line F1, the right angle boundary line F2, the short distance boundary line H1, and the long distance boundary line H2, as shown in the XY planar view image Im1 of FIG. 6. The detection range A when viewed in the YZ plane is the range where the detection region of the sensor unit 32 overlaps with the range surrounded by the front boundary line D1, the rear boundary line D2, the lower angle boundary line G1, the upper angle boundary line G2, the short distance boundary line H1, and the long distance boundary line H2, as shown in the YZ planar view image Im2 of FIG.

[0027] Next, the CPU 41 determines whether an operation input has been made to the front / rear (rear) boundary line input unit 50 (S102). Specifically, the CPU 41 determines whether either the slider S1 or the slider S2 has been moved relative to the slide bar B in the front / rear (rear) boundary line input unit 50, and whether either the numerical values ​​displayed in the display input field Q1 or the display input field Q2 have been changed based on an operator's operation. If it determines that an operation input has been made to the front / rear (rear) boundary line input unit 50, the CPU 41 changes the display of the front / rear (rear) boundary line input unit 50 while changing the display of either the rear boundary line D2 or the front boundary line D1, whichever has been operated and input, in the XY planar view image Im1 and the YZ planar view image Im2 displayed in the detection range display field C2, thereby changing the display of the detection range A defined by the front boundary line D1 and the rear boundary line D2 (S104). The display of the front / rear (rear) boundary line input section 50 is changed by updating the display of the corresponding numerical value in the display input field Q1 or Q2 when the sliders S1 or S2 are moved, and by moving the corresponding one of the sliders S1 or S2 to the position corresponding to the numerical value in the display input field Q1 or Q2 when the numerical value in the display input field Q1 or Q2 is changed.

[0028] If it is determined that the front / rear (rear) boundary line input unit 50 has not been operated, the CPU 41 determines whether the left / right boundary line input unit 60 has been operated (S106). Specifically, the CPU 41 determines whether either the slider S1 or the slider S2 has been moved relative to the slide bar B in the left / right boundary line input unit 60, or whether either the numerical value displayed in the display input field Q1 or the display input field Q2 in the left / right boundary line input unit 60 has been changed based on an operator's operation. If it is determined that the left / right boundary line input unit 60 has been operated, the CPU 41 changes the display of the left / right boundary line input unit 60 while changing the display of either the left boundary line E1 or the right boundary line E2, whichever has been operated and input, in the XY planar view image Im1 displayed in the detection range display field C2, thereby changing the display of the detection range A defined by the left boundary line E1 and the right boundary line E2 (S108). The display of the left and right boundary line input section 60 is changed by updating the display of the numerical value of the corresponding one of the display input fields Q1 and Q2 when the sliders S1 and S2 are moved, and by moving the corresponding one of the sliders S1 and S2 to the position corresponding to the numerical value of the display input fields Q1 and Q2 when the numerical value of the display input fields Q1 and Q2 is changed.

[0029] In this way, in the detection range setting process, the boundary line of the detection range A can be specified as a straight line. Therefore, even if there is a linear obstacle such as a wall or pillar within the detection range of the sensor unit 32, the detection range A can be set just right.

[0030] If it is determined that the left / right boundary line input unit 60 has not been operated, the CPU 41 determines whether the horizontal angle boundary line input unit 80 has been operated (S110). Specifically, the CPU 41 determines whether either the slider S1 or the slider S2 has been moved relative to the slide bar B in the horizontal angle boundary line input unit 80, or whether either the numerical values ​​displayed in the display input field Q1 or the display input field Q2 have been changed based on an operator's operation. If it is determined that the horizontal angle boundary line input unit 80 has been operated, the CPU 41 changes the display of the horizontal angle boundary line input unit 80, while changing the display of either the left angle boundary line F1 or the right angle boundary line F2, whichever has been operated and input, in the XY planar view image Im1 displayed in the detection range display field C2, thereby changing the display of the detection range A defined by the left angle boundary line F1 or the right angle boundary line F2 (S112). The display of the horizontal angle boundary line input section 80 is changed by updating the display of the numerical value of the corresponding one of the display input fields Q1 and Q2 when the sliders S1 and S2 are moved, and by moving the corresponding one of the sliders S1 and S2 to the position corresponding to the numerical value of the display input fields Q1 and Q2 when the numerical value of the display input fields Q1 and Q2 is changed.

[0031] If it is determined that the horizontal angle boundary line input unit 80 has not been operated, the CPU 41 determines whether the vertical angle boundary line input unit 90 has been operated (S114). Specifically, the CPU 41 determines whether either the slider S1 or the slider S2 has been moved relative to the slide bar B in the vertical angle boundary line input unit 90, or whether either the numerical values ​​displayed in the display input field Q1 or the display input field Q2 have been changed based on an operator's operation. If it is determined that the vertical angle boundary line input unit 90 has been operated, the CPU 41 changes the display of the vertical angle boundary line input unit 90 while changing the display of either the lower angle boundary line G1 or the upper angle boundary line G2, whichever has been operated and input, in the YZ planar view image Im2 displayed in the detection range display field C2, thereby changing the display of the detection range A defined by the lower angle boundary line G1 or the upper angle boundary line G2 (S116). The display of the vertical angle boundary line input section 90 is changed by updating the display of the corresponding numerical value in the display input field Q1 or Q2 when the sliders S1 or S2 are moved, and by moving the corresponding one of the sliders S1 or S2 to the position corresponding to the numerical value in the display input field Q1 or Q2 when the numerical value in the display input field Q1 or Q2 is changed.

[0032] If it is determined that the vertical angle boundary line input unit 90 has not received an input, the CPU 41 determines whether the distance boundary line input unit 70 has received an input (S118). Specifically, the CPU 41 determines whether either the slider S1 or the slider S2 has been moved relative to the distance boundary line input unit 70, and whether either the numerical values ​​displayed in the display input field Q1 or the display input field Q2 in the distance boundary line input unit 70 have been changed based on an operator's operation. If it is determined that the distance boundary line input unit 70 has received an input, the CPU 41 changes the display of the distance boundary line input unit 70, and also changes the display of either the short distance boundary R1 or the long distance boundary R2, whichever has been input, in the XY planar view image Im1 or the YZ planar view image Im2 displayed in the detection range display field C2, thereby changing the display of the detection range A defined by the short distance boundary R1 or the long distance boundary R2 (S120). The display of the distance boundary line input section 70 is changed by updating the display of the corresponding numerical value in the display input field Q1 or Q2 when the sliders S1 or S2 are moved, and by moving the corresponding one of the sliders S1 or S2 to the position corresponding to the numerical value in the display input field Q1 or Q2 when the numerical value in the display input field Q1 or Q2 is changed.

[0033] In this way, in the detection range setting process, the boundary lines of the detection range can also be set as distance and angle ranges in a polar coordinate system, allowing the operator to set the detection range A as desired by combining it with the boundary lines in a Cartesian coordinate system.

[0034] After S104, S108, S112, S116, S120, or after determining in S118 that no operation input has been made to the distance boundary line input unit 70, the CPU 41 determines whether the setting of the detection range A has been completed (S122). Specifically, the CPU 41 determines whether the save button on the setting screen Sc has been selected. If it is determined that the setting of the detection range A has not been completed, the CPU 41 returns to S102. If it is determined that the setting of the detection range A has been completed, the CPU 41 registers the area surrounded by the boundary lines as the detection range A (S124). An example of the detection range A set in this manner is shown in FIG. 6. Then, the CPU 41 outputs the Cartesian coordinate system boundary lines and polar coordinate system boundary lines of the set detection range A to the safety device 30 (S126), and ends this process.

[0035] Next, the operation of the safety device 30 when the robot main body 10 (articulated arm 12) is operating will be described. The robot main body 10 operates with the setting device 40 and the safety device 30 separated. In this embodiment, a detection process executed by the control unit (CPU) of the safety device 30 will be described. FIG. 7 is a flowchart showing an example of the detection process. This process detects an object included in a detection range A of the detection area of ​​the sensor unit 32, and is executed at predetermined time intervals (for example, every few ms).

[0036] In the detection process, the control unit 31 acquires the detection value of an object detected within the detection area by the sensor unit 32 as three-dimensional polar coordinate values ​​(distance L, horizontal angle θ, vertical angle φ) (S200). The vertical angle φ is the angle between the XY plane and a line segment connecting the origin and the detection point in the above-described three-dimensional Cartesian coordinate system, as shown in FIG. 4 . The horizontal angle θ is the angle between the Y axis and a line segment passing through the origin and the intersection of a perpendicular line drawn from the detection point onto the XY plane with the XY plane in the Cartesian coordinate system.

[0037] Next, the control unit 31 determines whether the distance L is equal to or greater than the short distance boundary R1 and equal to or less than the long distance boundary R2 (S202). The short distance boundary R1 and the long distance boundary R2 are set in the detection range setting process described above. If the control unit 31 determines that the distance L is less than the short distance boundary R1 or greater than the long distance boundary R2, the control unit 31 determines that the detected value is not within the detection range A and ends this process.

[0038] If the control unit 31 determines that the distance L is equal to or greater than the short distance boundary R1 and equal to or less than the long distance boundary R2, the control unit 31 determines whether the horizontal angle θ is equal to or greater than the left angle boundary α1 and equal to or less than the right angle boundary α2 (S204). If the control unit 31 determines that the horizontal angle θ is less than the left angle boundary α1 or greater than the right angle boundary α2, the control unit 31 determines that the detected value is not within the detection range A and ends this process.

[0039] If the control unit 31 determines that the horizontal angle θ is equal to or greater than the left angle boundary α1 and equal to or less than the right angle boundary α2, the control unit 31 determines whether the vertical angle φ is equal to or greater than the lower angle boundary β1 and equal to or less than the upper angle boundary β2 (S206). If the control unit 31 determines that the vertical angle φ is less than the lower angle boundary β1 or greater than the upper angle boundary β2, the control unit 31 determines that the detected value is not within the detection range A and ends this process.

[0040] If it is determined that the vertical angle φ is equal to or greater than the lower angle boundary β1 and equal to the upper angle boundary β2, the control unit 31 converts the polar coordinate values ​​of the detected values ​​into Cartesian coordinate values ​​in a three-dimensional Cartesian coordinate system (S208). Specifically, the control unit 31 converts the polar coordinate values ​​of the detected values ​​into Cartesian coordinate values ​​using the following equations (11) to (13).

[0041] X=L・cos(φ)・sin(θ)…(11) Y=L・cos(φ)・cos(θ)…(12) Z=L・sin(θ)…(13)

[0042] Next, the control unit 31 determines whether the X-axis coordinate value of the detected value is equal to or greater than the X-axis coordinate value (E1) of the left boundary line E1 and equal to or less than the X-axis coordinate value (E2) of the right boundary line E2 (S210). If the control unit 31 determines that the X-axis coordinate value of the detected value is less than the X-axis coordinate value of the left boundary line E1 or greater than the X-axis coordinate value of the right boundary line E2, the control unit 31 determines that the detected value is not within the detection range A and ends this process.

[0043] If the control unit 31 determines that the X-axis coordinate value of the detected value is equal to or greater than the X-axis coordinate value of the left boundary line E1 and equal to or less than the X-axis coordinate value of the right boundary line E2, the control unit 31 determines whether the Y-axis coordinate value of the detected value is equal to or greater than the Y-axis coordinate value (D1) of the back boundary line D2 and equal to or less than the Y-axis coordinate value (D2) of the front boundary line D1 (S212). If the control unit 31 determines that the Y-axis coordinate value of the detected value is less than the Y-axis coordinate value of the back boundary line D2 or greater than the Y-axis coordinate value of the front boundary line D1, the control unit 31 determines that the detected value is not within the detection range A and terminates this process.

[0044] If the control unit 31 determines that the Y-axis coordinate value of the detected value is equal to or greater than the Y-axis coordinate value of the back boundary line D2 and equal to or less than the Y-axis coordinate value of the front boundary line D1, the control unit 31 determines that the detected value is within the detection range A and sets a speed limit value according to the distance L to the object acquired in S200 (S214).The control unit 31 then outputs the generated speed limit value to the robot control device 20 (S216) and ends this process.The speed limit value is the ratio of the target speed to the speed command value.The speed limit value is set in the range from 0 to 1, and is set to, for example, 0, 0.25, 0.5, 0.75, or 1. For example, the control unit 31 sets the speed limit value to 0 when the distance L is 0 to 500 mm, sets the speed limit value to 0.25 when the distance L is 500 to 1000 mm, sets the speed limit value to 0.5 when the distance L is 1000 to 1500 mm, sets the speed limit value to 0.75 when the distance L is 1500 to 2000 mm or more, and sets the speed limit value to 1 when the distance L is 2000 mm or more. The control unit 21 of the robot control device 20 multiplies the speed command value by the speed limit value to set the target speed.

[0045] In this way, in the robot system 1, a control command value is generated based on the distance L from the safety device 30, and a target speed is set based on the command value. Therefore, the target speed can be set according to the distance L from the safety device 30.

[0046] Here, the correspondence between the main elements of the embodiment and the main elements of the present disclosure described in the claims will be described. That is, the setting device 40 and the safety device 30 of the embodiment correspond to the sensor system of the present disclosure, the CPU 41 that executes the processes of S102, S106, S110, S114, and S118 of the detection range setting process corresponds to the input unit, the CPU 41 that executes the process of S124 of the effective range setting process corresponds to the range setting unit, and the control unit 31 that executes the detection process corresponds to the detection unit.

[0047] It goes without saying that the present disclosure is not limited to the above-described embodiments, and can be embodied in various forms as long as they fall within the technical scope of the present disclosure.

[0048] In the above-described embodiment, the control unit 31 of the safety device 30 converts the detection value of the sensor unit 32 into a Cartesian coordinate system and determines whether the Cartesian coordinate value of the detection value falls within the detection range A of the Cartesian coordinate system. However, the boundary of the detection range A in the Cartesian coordinate system may be converted into a polar coordinate system and whether the detection value in the polar coordinate system falls within the detection range A of the polar coordinate system may be determined. The detection range setting process in this case is shown in FIG. 8 . Note that in FIG. 8 , the same steps as those in FIG. 3 are assigned the same step numbers and will not be described again to avoid duplication. After S120, the CPU 41 of the setting device 40 converts the boundary of the detection range A in the Cartesian coordinate system into a polar coordinate system (S300) using the following equations (14) to (17) and outputs the converted value (S126). Equation (14) represents a point on the left boundary line E1 as a combination of a length M1 and a horizontal angle γ1. Note that, as shown in FIG. 9 , length M1 is the length of the line segment connecting a point on the left boundary line E1 shown in the above-described equation (3) to the origin O. As shown in FIG. 9 , the horizontal angle γ1 is the angle between the line segment and the Y-axis. Equation (15) is an equation that expresses a point on the right boundary line E2 as a combination of the length M2 and the horizontal angle γ2. As shown in FIG. 9 , the length M2 is the length of the line segment connecting the point on the right boundary line E2, expressed by the above-mentioned equation (4), to the origin O. As shown in FIG. 9 , the horizontal angle γ2 is the angle between the line segment and the Y-axis. Furthermore, equation (16) is an equation that expresses a point on the front boundary line D1 as a combination of the length N1 and the horizontal angle γ1. As shown in FIG. 9 , the length N1 is the length of the line segment connecting the point on the front boundary line D1, expressed by the above-mentioned equation (1), to the origin O. As shown in FIG. 9 , the horizontal angle δ1 is the angle between the line segment and the Y-axis. Finally, equation (17) is an equation that expresses a point on the back boundary line D2 as a combination of the length N2 and the horizontal angle γ2. 9, the length N2 is the length of the line segment connecting a point on the rear boundary line D2 expressed by the above-mentioned formula (2) with the origin O. The horizontal angle δ2 is the angle between the line segment and the Y axis, as shown in FIG.

[0049] (M1 / E1)・sin(γ1)=1...(14) (M2 / E2)・sin(γ2)=1...(15) (N1 / D1)・cos(δ1)=1...(16) (N2 / D2)・cos(δ2)=1...(17)

[0050] Then, the control unit 31 of the safety device 30 executes the detection process shown in Fig. 10. That is, after S206, the CPU 41 determines whether the distance L and the horizontal angle θ are within the range of the combination of the distances M1, M2, N1, and N2 and the horizontal angles γ1, γ2, δ1, and δ2 determined by equations (14) to (17) (S400). If it is determined that the distance L and the horizontal angle θ are not within the range of the combination of the distances M1, M2, N1, and N2 and the horizontal angles γ1, γ2, δ1, and δ2 determined by equations (14) to (17), the control unit 31 determines that the detected value is not within the detection range A, and ends the detection process.

[0051] If it is determined that the distance L and the horizontal angle θ are within the range of the combination of distances M1, M2, N1, N2 and horizontal angles γ1, γ2, δ1, δ2 determined by equations (14) to (17), the control unit 31 sets a speed limit value according to the distance L (S218), outputs the speed limit value to the robot control device 20 (S220), and terminates the detection process.

[0052] In the above-described embodiment, in the detection range setting process, a line parallel to the X axis and a line parallel to the Y axis on the XY planar image Im1 can be set as the boundary line of the detection range A. However, a line parallel to the Y axis on the YZ planar image Im2 may also be set as the boundary line.

[0053] In the above-described embodiment, the safety device 30 is attached to the hand (tip) of the articulated arm 12 of the robot main body 10. However, it may also be attached to the base 11 of the robot main body 10. Furthermore, while the safety device 30 is provided on a stationary robot, it may also be provided on a self-propelled robot. The self-propelled robot may be an arm robot with the above-described articulated arm, or a transport robot. For example, as shown in FIG. 11 , in a mounting line 100 having feeder tables arranged in the transport direction of a board and each having a detachable feeder 102, and including multiple component mounters 101 that pick up components from the feeders 102 and mount them on the board, an automatic exchange robot 110 may move along the mounting line 100 to exchange the feeders 102 for each component mounter 101. The safety device 30 is provided on the automatic exchange robot 110, and when an interfering object is detected within the detection range, it outputs a command value to the automatic exchange robot 110 according to the distance to the object. The automatic exchange robot 110 sets a target speed by limiting a speed command value using an input speed limit value.

[0054] In the above-described embodiment, the processes of S200 to S216 of the detection process are executed by the control unit 31 of the safety device 30. However, at least a part of the processes of S200 to S214 may be executed by the control unit 21 of the robot control device 20.

[0055] In the above-described embodiment, the sensor unit 32 has a three-dimensional detection area. However, the sensor unit 32 may have a two-dimensional detection area. In this case, the sensor unit 32 may have, for example, a fan-shaped detection area in the horizontal direction.

[0056] In the above-described embodiment, the control unit 31 of the safety device 30 sets the speed limit value based on the distance L. However, the control unit 31 may set the speed limit value based on the distance L and the speed of the object. In this case, the control unit 31 may set the speed limit value based on the distance L and the speed of the object so that the robot speed is more greatly limited as the time it takes for the object to reach the robot main body 10 (articulated arm 12) becomes shorter.

[0057] In the above-described embodiment, the setting conditions for the boundary lines of the detection range A are input by changing the input values ​​in the display input fields Q1 and Q2 in the setting condition input field C1 or by moving the sliders S1 and S2 relative to the slide bar B. However, the setting conditions for the boundary lines of the detection range A may also be input by the operator moving the boundary lines in the detection range display field C2 using a mouse or the like. In this case, for example, the setting conditions for each boundary line in the image displayed in the detection range display field C2 may be input by dragging and dropping the boundary lines.

[0058] As described above, in the sensor system of the present disclosure, the boundary lines of the detection range can be set as straight lines, so that the detection range can be set just right.

[0059] The sensor system of the present disclosure may further include a detection unit that detects the object present in the detection range when the output value of the sensor is within the detection range. In this way, the object present in the detection range can be detected.

[0060] In the sensor system of the present disclosure, the straight boundary line set by the setting unit may be a straight line in a Cartesian coordinate system based on a predetermined point on the sensor, which makes it possible to set the straight boundary line relatively easily.

[0061] In the sensor system of the present disclosure, the input unit may be capable of inputting, as the detection range condition, a condition for defining a straight line in a Cartesian coordinate system based on a predetermined point of the sensor, the setting unit may set the detection range in a polar coordinate system using a conversion parameter, and the detection unit may detect the object present in the detection range based on the output value in the polar coordinate system of the sensor and the detection range in the polar coordinate system. In this way, it is possible to determine whether the output value is included in the detection range using the output value in the polar coordinate system of the sensor as is.

[0062] In the sensor system of the present disclosure, the input unit may be capable of inputting, as the detection range condition, a condition for defining a straight line in a Cartesian coordinate system based on a predetermined point of the sensor, the setting unit may set the detection range in the Cartesian coordinate system, and the detection unit may convert the polar coordinate values ​​of the output value into Cartesian coordinate values ​​in the Cartesian coordinate system using a conversion parameter, and detect the object present in the detection range based on the detection value in the Cartesian coordinate system and the detection range in the Cartesian coordinate system. In this way, it is possible to determine whether the detection value is included in the detection range with a relatively simple process.

[0063] In the sensor system of the present disclosure, the input unit may be capable of inputting the boundary line of the detection range as an angle and distance in a polar coordinate system within a predetermined distance range and a predetermined angle range that define the detection range, and the range setting unit may set the detection range based on the input angle and distance. In this way, the detection range can be set to a more desired range.

[0064] In the sensor system of the present disclosure, the input unit may be capable of inputting a line parallel to a first axis in a three-dimensional Cartesian coordinate system and a line parallel to a second axis orthogonal to the first axis, and the setting unit may set the three-dimensional detection range. In this way, the boundary line of the detection range in three-dimensional space can be input as a line.

[0065] The sensor system of the present disclosure may also include a display unit and a display control unit that displays the detection range on the display unit and updates the display when the boundary line is input and the detection range is set. This allows the operator to check the changed detection range each time the detection range is changed, making it easier to set the detection range. In this case, the display control unit may control the display unit to display the position of the boundary line that is set in accordance with an input value input to the input unit. This allows the boundary line to be displayed based on a direct input. In these cases, the input unit may be capable of inputting conditions for the detection range based on movement of an operation object displayed on the display unit, and the display control unit may control the display unit to display the position of the boundary line that is set based on operation of the operation object. This allows the boundary line to be set by intuitive operation.

[0066] The sensor system of the present disclosure may also include an output unit that generates a command value capable of restricting the robot's operation based on the detection result of an object present within the detection range and outputs the command value to the robot. In this way, obstacles can be detected within an appropriate detection range, allowing the robot to operate safely.

[0067] The specification also discloses the technical idea of ​​changing "the sensor system according to claim 1 or 2" in claim 6 at the time of filing to "the sensor system according to any one of claims 1 to 5," the technical idea of ​​changing "the sensor system according to claim 1 or 2" in claim 7 at the time of filing to "the sensor system according to any one of claims 1 to 6," the technical idea of ​​changing "the sensor system according to claim 1" in claim 8 at the time of filing to "the robot system according to any one of claims 1 to 7," and the technical idea of ​​changing "the sensor system according to claim 1 or 2" in claim 11 at the time of filing to "the sensor system according to any one of claims 1 to 10."

[0068] The present disclosure is applicable to the robot manufacturing industry and the like.

[0069] 1 Robot system, 10 Robot body, 11 Base, 12 Articulated arm, 15 Servo motor, 16 Encoder, 17 Amplifier unit, 20 Robot control device, 21 Control unit, 22 I / O port, 30 Safety device, 31 Control unit, 32 Sensor unit, 33 I / O port, 40 Setting device, 41 CPU, 42 ROM, 43 RAM, 44 Storage, 45 I / O port, 46 Input device, 47 Display device, 50 Forward / backward slide bar, 51, 52 Slider, 53, 54 Display column, 60 Left / right slide bar, 61, 62 Slider, 63, 64 Display column, 70 Horizontal slide bar, 71, 72 Slider, 73, 74 Display column, 80 Vertical slide bar, 81, 82 Slider, 83, 84 Display column, 90 Arc slide bar, 91, 92 sliders, 93, 94 display field, 100 mounting line, 101 component mounter, 102 feeder, 110 automatic exchange robot, A detection range, C1 setting condition input field, C2 detection range display field, Im1 XY planar image, Im2 YZ planar image, L distance, L1 distance, L2 distance, M1 distance, M2 distance, O origin, R1 near distance boundary, R2 far distance boundary, Sc setting screen, α1 left angle boundary, α2 right angle boundary, β1 lower angle boundary, β2 upper angle boundary, γ1 horizontal angle, γ2 horizontal angle, δ1 horizontal angle, δ2 horizontal angle, θ horizontal angle, φ vertical angle.

Claims

1. A sensor system including a sensor capable of detecting an object contained in a sector-shaped detection area, the sensor outputting the relative position of the object present in the detection area as a polar coordinate value in a polar coordinate system with the sensor as the origin; an input unit capable of inputting detection range conditions for detecting objects in the detection area; and a setting unit that sets the detection range of the sensor as a straight line boundary line based on the input detection range conditions.

2. A sensor system according to claim 1, comprising a detection unit that detects the object present within the detection range when an output value of the sensor is within the detection range.

3. A sensor system according to claim 1 or 2, wherein the boundary line of the straight line set by the setting unit is a straight line in an orthogonal coordinate system based on a predetermined point of the sensor.

4. A sensor system as described in claim 2, wherein the input unit is capable of inputting conditions for determining a straight line in a Cartesian coordinate system based on a predetermined point of the sensor as conditions for the detection range, the setting unit sets the detection range in the polar coordinate system using conversion parameters, and the detection unit detects the object present in the detection range based on the output value of the polar coordinate system of the sensor and the detection range in the polar coordinate system.

5. A sensor system as described in claim 2, wherein the input unit is capable of inputting conditions for determining a straight line in a Cartesian coordinate system based on a predetermined point of the sensor as conditions for the detection range, the setting unit sets the detection range in the Cartesian coordinate system, and the detection unit converts the polar coordinate values ​​of the output values ​​into Cartesian coordinate values ​​in the Cartesian coordinate system using conversion parameters, and detects the object present in the detection range based on the output value in the Cartesian coordinate system and the detection range in the Cartesian coordinate system.

6. A sensor system as claimed in claim 1 or 2, wherein the input unit is capable of inputting the detection range conditions as angles and distances in a polar coordinate system within a predetermined distance range and a predetermined angle range that define the detection area, and the setting unit sets the detection range based on the inputted angle and distance.

7. A sensor system as claimed in claim 1 or 2, wherein the input unit is capable of inputting a straight line parallel to a first axis in a three-dimensional Cartesian coordinate system and a straight line parallel to a second axis perpendicular to the first axis, and the setting unit sets the three-dimensional detection range.

8. A sensor system as described in claim 1, comprising: a display unit; and a display control unit that displays the detection range on the display unit, and updates the display when conditions for the detection range are input and the detection range is set.

9. A sensor system according to claim 8, wherein the display control unit controls the display unit to display the position of the boundary line that is set according to an input value input to the input unit.

10. A sensor system as described in claim 8 or 9, wherein the input unit is capable of inputting conditions for the detection range based on the movement of an object to be operated displayed on the display unit, and the display control unit controls the display unit to display the position of the boundary line that is set based on the operation of the object to be operated.

11. A sensor system as claimed in claim 1 or 2, comprising an output section which generates a command value capable of restricting the movement of the robot based on the detection result of an object present within the detection range, and outputs the command value to the robot.

Images