JP4750200B2 - Robot movement range setting device - Google Patents

Description

  The present invention relates to a robot operation range setting device for setting an operation range of an industrial robot (hereinafter referred to as “robot”).

  In factories and the like, robots are used to perform various operations with work tools attached to their hands. Alternatively, the robot may perform various operations while holding the workpiece on the robot hand. When performing such work, it is necessary to prevent the work tool and the like from interfering with peripheral devices of the robot. Patent Document 1 discloses a method for setting the operation range of a work tool so that the work tool does not interfere with peripheral devices.

  By the way, normally, a robot control device has an operation range monitoring function. When each axis or tool tip point of the robot moves out of the set operation range, this operation range monitoring function cuts off the power to the robot motor, thereby stopping the robot. Become so. As a result, each axis of the robot or the work tool is prevented from colliding with peripheral devices.

JP 7-12215 A

  However, in actuality, even after the power to the motor of the robot is cut off, each axis of the robot runs slightly. Therefore, the position at which the robot stops deviates from the set operation range of each axis and the like by the coasting distance, so that each axis of the robot collides with the peripheral device.

  Therefore, it is desirable to set the movement range of the robot to be smaller than the actual reach range in consideration of the coasting distance. However, since the coasting distance varies depending on the operation speed of the robot and / or the load weight of the work tool or the like, it is difficult for the operator to set the operation range while assuming the actual reachable range. For this reason, there has been a problem that it takes a considerable time for the operator to set the operation range. Furthermore, in Patent Document 1, such a coasting distance is not considered.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a robot motion range setting device capable of creating a robot reach range that takes into account the coasting distance of the robot.

  In order to achieve the above-described object, according to a first aspect of the present invention, there is provided a setting means for setting an operation range of each axis of a robot and a work tool; Based on the storage means for storing the coasting distance of the robot determined in accordance with the movement range set by the setting means and the coasting distance stored in the storage means, the reach range to be reached by the robot is calculated. A robot operation range setting device comprising a reach range calculation means is provided.

  That is, in the first invention, the reach range of the robot in which the coasting distance is considered can be created by the reach range calculation means. As a result, the operator can adjust the movement range of the robot once set based on the created reach range.

According to a second aspect, in the first aspect, the information processing apparatus further comprises display means for displaying the reach range calculated by the reach range calculation means.
That is, in the second invention, since the operator can refer to the reach range displayed on the display means, the operation range can be easily adjusted.

According to the third invention, in the first or second invention, it is further confirmed whether or not there is interference between the reach range calculated by the reach range calculation means and the peripheral device of the robot. Interference confirmation means is provided.
That is, in the third invention, since the presence or absence of interference can be confirmed before the robot is actually operated, the operation range can be easily adjusted. As a result, it is possible to avoid a robot work tool or the like from actually colliding with a peripheral device.

According to a fourth invention, in the third invention, when it is confirmed by the interference confirmation means that there is interference between the reachable range and the peripheral device, each axis of the robot and the robot Adjusting means for adjusting the operating range of the work tool to eliminate the interference is provided.
That is, in the fourth aspect of the invention, it is possible to create an operating range that does not interfere with peripheral devices. As a result, it is possible to eliminate the necessity for the operator to adjust the once set operation range.

1 is a schematic diagram of a robot system including a robot control device according to the present invention. 2 is a schematic diagram of the robot system shown in FIG. 1. It is a flowchart which shows operation | movement of the robot control apparatus based on this invention. (A) It is a 1st figure for demonstrating the calculation method of the reach from an operation | movement range. (B) It is a 2nd figure for demonstrating the calculation method of the reach from an operation | movement range. (C) It is a 3rd figure for demonstrating the calculation method of the reach from an operation | movement range. It is a figure which shows the map of coasting distance. It is a figure which shows the movement range and reach | attainment range which the robot set. 6 is a schematic diagram of another embodiment of a robot system with a robot controller according to the present invention.

Embodiments of the present invention will be described below with reference to the accompanying drawings. In the following drawings, the same members are denoted by the same reference numerals. In order to facilitate understanding, the scales of these drawings are appropriately changed.
FIG. 1 is a schematic diagram of a robot system equipped with a robot control apparatus according to the present invention. The robot 20 shown in FIG. 1 is a six degrees of freedom vertical articulated robot. A work tool 21 is attached to the tip of the arm of the robot 20. Alternatively, instead of the work tool 21, a hand (not shown) for gripping the workpiece may be attached to the tip of the arm.

  A teaching control panel 40 having an LCD 41 and a keyboard 42 is connected to the robot control device 30 that controls the robot 20. The operator can browse information inside the robot control device 30 through the LCD 41. Further, the operator can input and change various programs and various data of the robot control device 30 through the keyboard 42 of the teaching control panel 40.

  Specifically, the operator can input and change the movement range of each axis of the robot 20 and the movement range of the tool tip point of the work tool 21 through the keyboard 42. Hereinafter, the operation range of each axis of the robot 20 and the operation range of the tool tip point of the work tool 21 are collectively referred to simply as “operation range”. Furthermore, the operator can input and change the coasting distance h, the dimension data of the arm of the robot 20, the dimension data of the equipment of the robot 20, and the dimension data of the peripheral device 50 through the keyboard 42. Note that various input data and the like are stored in the storage unit 33 of the robot control device 30.

  FIG. 2 is a schematic diagram of the robot system shown in FIG. As illustrated in FIG. 2, the robot control device 30 includes a control unit 31 including a CPU 32 and a storage unit 33, for example, a digital computer. In the embodiment shown in FIG. 2, the CPU 32 functions as a robot operation range setting device. The CPU 32 calculates the reach range calculation means 36 for calculating the reach range X1 of each axis of the robot 20 and the tool tip of the work tool 21, and whether there is interference between the calculated reach range X1 and the peripheral device 50. Interference confirmation means 37 for confirming the above and automatic adjustment means 38 for eliminating the interference by adjusting the operation range X0. Note that the reach range X1 of each axis of the robot 20 and the tool tip point of the work tool 21 is collectively referred to as an reach range X1 below.

  Various data input by the teaching control panel 40 are stored in the storage unit 33 of the robot control device 30. The storage unit 33 stores a ROM in which various system programs are stored, a RAM that is used by the CPU 32 to temporarily store data, various programs related to robot operation contents, related setting values, and a map that will be described later. Non-volatile memory.

  The servo motor 25 provided in the arm of the robot 20 includes a position detector 26, for example, an encoder. The position detector 26 detects the position of the rotating shaft of the servo motor 25 and transmits the position information to the control unit 31 through the servo amplifier 35. The servo amplifier 35 supplies power to the servo motor 25 of the robot 20. Furthermore, as shown in FIG. 2, the robot control device 30 includes an emergency stop means 34 that cuts off the power supply to the servo amplifier 35 in response to a command from the control unit 31 as an operation monitoring function.

  FIG. 3 is a flowchart showing the operation of the robot control apparatus according to the present invention. FIG. 4A to FIG. 4C are diagrams for explaining a calculation method of the reachable range from the operating range. Hereinafter, the operation of the robot control apparatus 30 according to the present invention will be described with reference to FIGS. 3 and 4. It is assumed that the operator has already set the operation range X0 of the robot 20 through the teaching control panel 40 before the flowchart shown in FIG.

  In step 101 of FIG. 3, first, the operation range X0 is displayed on the LCD 41 of the teaching control panel 40. Next, as shown in FIG. 4A, on the LCD 41, a three-dimensional lattice 61 having a predetermined size is arranged in the operation range X0. The three-dimensional lattice 61 is arranged so as to be inscribed in the operation range X0.

  Next, in step 102, the coasting distance h is added at each vertex of the three-dimensional lattice 61. Specifically, as shown in FIG. 4B, a sphere 62 having a radius corresponding to the coasting distance h is arranged at each vertex of the three-dimensional lattice 61. For the sake of brevity, the sphere 62 is arranged only at the apex of the entire three-dimensional lattice 61 in FIG.

  Here, FIG. 5 is a diagram showing a map of the coasting distance. As shown in FIG. 5, the coasting distance h is obtained in advance in the form of a map as a function of the moving speed V of the robot 20 and the weight W of the work tool 21. The weight W of the work tool 21 is determined according to the work content of the robot 20. The moving speed V of the robot 20 is calculated based on the position of the robot 20 periodically detected by the position detector 26. The coasting distance h is obtained from a map as shown in FIG.

  Alternatively, when a hand (not shown) is attached instead of the work tool 21, the coasting distance h is the total weight of the moving speed V of the robot 20 and the work (not shown) gripped by the hand and the hand. It is assumed that it is obtained as a function of The coasting distance h input from the teaching control panel 40 by the operator may be used.

  Next, in step 103, the reachable range X1 to which the coasting distance h is added is calculated. Specifically, the reachable range X1 is calculated so as to circumscribe all of the plurality of spheres 62 shown in FIG. 4C, and is displayed on the LCD 41. As shown in the figure, the calculated reachable range X1 is slightly larger than the operating range X0. The arrangement of the three-dimensional lattice 61 and the sphere 62 and the calculation of the reach range X1 are performed by the reach range calculation means 36 of the robot control device 30. Next, in step 104, the three-dimensional lattice 61 and the sphere 62 are deleted, and the reachable range X1 and the operating range X0 are displayed on the LCD 41.

  FIG. 6 is a diagram showing the set motion range and reach range of the robot. In FIG. 6, in addition to the reachable range X1 and the motion range X0, the robot 20 and peripheral devices 50 arranged on the left and right of the robot 20 are also displayed on the LCD 41.

  In step 105, the interference confirmation unit 37 confirms whether or not the reachable range X1 interferes with the peripheral device 50. In FIG. 6, since a part X11 of the reachable range X1 is drawn on the right peripheral device 50, the robot 20 may interfere with the right peripheral device 50 in this part X11. Hereinafter, a part X11 of the reachable range X1 is referred to as an interference part X11.

  In such a case, the operator adjusts the once set motion range X0 based on the reach range X1. Since the reachable range X1 and the motion range X0 are displayed on the LCD 41, the operator can easily adjust the motion range X0 while referring to the reachable range X1. Therefore, the operator can easily eliminate interference between the robot 20 and the peripheral device 50.

  Further, the adjustment of the operation range X0 may be automatically performed by the automatic adjustment unit 38 of the robot control device 30. In such a case, the process proceeds to step 106. In step 106, the automatic adjustment means 38 automatically changes the operating range X0 according to the interference portion X11.

  Specifically, a part X00 of the operation range X0 corresponding to the interference part X11 is extracted. Next, the portion X00 is moved toward the robot 20 by a predetermined minute distance Δh. As a result, a new operation range X0 ′ is created. Then, it returns to step 101 and repeats the operation mentioned above.

  If it is determined in step 105 that there is interference in the new arrival range X1 ′, the process proceeds to step 106, where the robot 20 moves a portion X00 ′ corresponding to the interference portion X11 ′ of the arrival range X1 ′ by a minute distance Δh. Move further towards. In this way, the process is repeated until no new interference portion occurs. This eliminates the need for the operator to adjust the movement range X0 to the movement range X0 ′.

  Thus, in the present invention, the reach range calculating means 36 calculates the reach range X1 in which the coasting distance h is considered, and when there is interference with the peripheral device 50, the motion range X0 is set as the reach range. Adjustment is made based on X1. Therefore, in the present invention, it is possible to avoid beforehand that the work tool 21 of the robot 20 collides with the peripheral device 50.

  In the embodiment described with reference to the drawings, the reach range calculation means 36 calculates the reach range X 1 by arranging the sphere 62 at the apex of the three-dimensional lattice 61. However, the reachable range X1 in which the coasting distance h is considered may be calculated by other methods.

  2 is activated when each axis of the robot 20 and the work tool 21 deviate from the operation range X0 when the robot 20 is actually operated. Thereby, the power supply to the servo amplifier 35 is cut off. As a result, the servo motor 25 does not receive power, and the robot 20 stops. Therefore, the emergency stop means 34 can also prevent the work tool 21 of the robot 20 and the like from actually colliding with the peripheral device 50.

  FIG. 7 is a schematic diagram of another embodiment of a robot system with a robot controller according to the present invention. In this embodiment, the robot control device 30 and the robot motion range setting device 302 are separate devices, and the robot motion range setting device 302 is connected to the robot control device 30.

  As illustrated, the robot motion range setting device 302 includes a CPU 320, a storage unit 303, a display unit 304, and a keyboard 305. Further, the CPU 320 includes a reach range calculation unit 306, an interference confirmation unit 307, and an automatic adjustment unit 308.

  The operator can set the operation range through the keyboard 305. Furthermore, the operator can input and change the coasting distance h, the dimension data of the arm of the robot 20, the dimension data of the equipment of the robot 20, and the dimension data of the peripheral device 50 through the keyboard 305. In addition, various input data and the like are stored in the storage unit 303 of the robot operation range setting device 302.

  The reach range calculation means 306, the interference confirmation means 307, and the automatic adjustment means 308 shown in FIG. 7 are the same as the reach range calculation means 36, the interference check means 37, and the automatic adjustment means 38 shown in FIG. That is, the reach range calculation unit 306 calculates the reach range from the data stored in the storage unit 303. Then, the reachable range X1 and the operating range X0 are displayed on the display unit 304. In addition, the interference confirmation unit 307 confirms whether or not the reachable range X1 interferes with the peripheral device 50. Further, the automatic adjustment means 308 automatically changes the operating range X0 according to the interference portion X11.

  The robot operation range setting device 302 can save the data stored in the storage unit 303 in the memory card 301. The robot control device 30 can read data stored in the memory card 301 and store it in the storage unit 33.

  When the position of each axis of the robot 20 and the work tool 21 deviates from the operation range stored in the storage unit 33 when actually operating the robot 20, the CPU 32 of the robot control device 30 causes the emergency stop means 34. Start up. Thereby, the power supply to the servo amplifier 35 is cut off. As a result, the servo motor 25 does not receive power, and the robot 20 stops. Therefore, the emergency stop means 34 can also prevent the work tool 21 of the robot 20 and the like from actually colliding with the peripheral device 50.

DESCRIPTION OF SYMBOLS 20 Robot 21 Work tool 25 Servo motor 26 Position detector 30 Robot control apparatus 31 Control part 33 Memory | storage part 34 Emergency stop means 35 Servo amplifier 36,306 Arrival range calculation means 37,307 Interference confirmation means 38,308 Automatic adjustment means 40 Teaching Control panel (setting method)
41 LCD
42 Keyboard 50 Peripheral device 61 Three-dimensional lattice 62 Sphere 302 Robot motion range setting device X0 motion range X1 reach

Claims (4)

Setting means for setting the movement range of each axis and work tool of the robot,
Storage means for storing a coasting distance of the robot determined according to at least one of an operation speed of the robot and a weight of the work tool;
A reach range calculating means for calculating a reach range reached by each axis of the robot and the work tool based on the motion range set by the setting means and the coasting distance stored in the storage means;
Interference confirmation means for confirming whether or not the reach range calculated by the reach range calculation means includes an interference portion that interferes with peripheral devices of the robot;
An adjustment unit that adjusts each axis of the robot and the operation range of the work tool when the interference confirmation unit confirms that the reach includes the interference part;
The adjustment means extracts a part of the movement range corresponding to the interference part and creates a new movement range by moving the part by a predetermined distance toward the robot, thereby moving the movement range of the work tool. Robot movement range setting device that adjusts   The adjustment means repeatedly creates a new motion range until the new reach range calculated by the reach range calculation means does not include the interference portion using the new motion range. The robot operation range setting device described in 1.   The robot operation range setting device according to claim 1, further comprising display means for displaying the reach range calculated by the reach range calculation means.   The reach range calculation means arranges a three-dimensional grid having a predetermined size so as to be inscribed in the operation range on the display means, and a sphere having a radius corresponding to the coasting distance is set at each vertex of the three-dimensional grid. The robot motion range setting device according to claim 1, wherein the robot motion range setting device is arranged to calculate a reach range so as to circumscribe all the spheres.

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