JP4124583B2 - Method and apparatus for creating operation path data of work robot - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method and apparatus for creating motion path data including the movement speed of a work robot with respect to a plurality of work points.
[0002]
[Prior art]
Conventionally, if the work robot installed on the production line is directly operated to teach the work posture, an operator who is familiar with the operation of the work robot must work at the site of the production line. Becomes inefficient. Moreover, since it is necessary to perform such work in a state where the production line is stopped, the operation rate of the production line is also lowered.
[0003]
Therefore, recently, offline teaching has been performed in order to increase the efficiency of the teaching work or to improve the operating rate of the production line. That is, by constructing a model of a work robot and a work and peripheral structures that are work objects on a computer, and creating teaching data using this model, the teaching data is supplied to the work robot on site, Teaching data can be created efficiently without stopping the production line.
[0004]
By the way, in such off-right teaching, for example, when the operator designates a plurality of work points, the computer automatically calculates the operation path data of the work robot in consideration of the specifications of the surrounding structure and the work robot. Is also becoming possible.
[0005]
However, teaching data is not composed of only motion path data, but is data that is completed only when motion specification parameters including the moving speed of the work robot are added to each motion path data. Conventionally, these operation specification parameters are set based on operator experience and trial and error.
[0006]
In this case, the motion specification parameter related to the moving speed is an important factor that determines the cycle time of the work robot. However, even if the moving speed is set to the maximum speed based on the specifications of the work robot, the cycle time is not necessarily shortened.
[0007]
For example, if the moving speed of the end effector is set fast, the time for stopping the end effector at the desired working point becomes long. On the other hand, if it is set too late, the time for reaching the working point becomes long. Also, in a production line where multiple work robots are arranged close to each other, there is a risk of interference between work robots having the same operating range due to the movement speed of the work robot. It may not be selectable as a speed.
[0008]
[Problems to be solved by the invention]
The present invention has been made in order to solve the above-mentioned problems, and the operation of the work robot that can automatically set the optimum moving speed of the work robot and thereby can shorten the cycle time. It is an object of the present invention to provide a route data creation method and apparatus.
[0009]
In order to solve the above-mentioned problem, in the method of the present invention, in the method of creating motion path data including the moving speed of the work robot with respect to a plurality of work points,
Set the allowable range in the relay point for avoiding interference between the work points constituting a plurality of individual operation path constituting the entire operation path, entire operation path including the allowable range of the working robot for said relay point Forming a plurality of
A plurality of movement speeds are set for the work robot moving to the work point, and the movement time to the work point is calculated for each movement speed for each individual movement path of the entire movement paths formed. Steps,
Selecting the movement speed at which the movement time is the shortest for each individual movement path of the entire movement paths formed ;
Determining the presence or absence of interference of the work robot operating at the selected moving speed for each individual movement path of the entire movement path formed ;
Total travel time for the mobile speed to be determined by the result as the shortest selected for each individual path of movement of each entire operation path in which the formed of the presence or absence of interference of the working robot for each whole each operation route of the formed Creating a recording table that records the cycle time of the entire operation path ;
Wherein the record table, the no interference with the work robot, and the cycle time determines the combination of the moving speed of the shortest and the entire name Ru said operating path and the selected shortest, based on the previous SL sets combined Creating motion path data;
With
The step of calculating the movement time is based on the time required for the work robot to reach the work point and the time required for the work robot to stop oscillating after reaching the work point. And calculating the travel time.
[0010]
In this case, the work robot is operated at each moving speed along the searched movement path, and the movement speed data including the movement speed is automatically created by determining the movement speed so that the movement time at that time becomes the shortest. Can do.
[0011]
Note that by determining whether or not there is interference when the work robot is operated at the movement speed selected as described above, an optimum movement speed without interference can be selected.
[0012]
In the device of the present invention, in the creation device of the operation path data including the moving speed of the work robot with respect to a plurality of work points,
Set the allowable range in the relay point for avoiding interference between the work points constituting a plurality of individual operation path constituting the entire operation path, entire operation path including the allowable range of the working robot relative to the working point A plurality of motion path search units,
A plurality of movement speeds are set for the work robot that moves to the work point, and the movement time to the work point is calculated for each movement speed for each individual movement path of the entire movement path that is formed. Travel time calculator,
A moving speed selecting unit that selects the moving speed at which the moving time is the shortest for each individual operation path of the entire formed operation path ;
An interference determination unit that determines the presence or absence of interference of the work robot that operates at the selected moving speed for each of the formed individual operation paths.
With
The movement time calculation unit is configured to perform the movement based on a time required for the work robot to reach the work point and a time required for the work robot to stop oscillating after the work robot reaches the work point. Calculate the time,
The result of the presence / absence of interference of the work robot determined for each of the formed movement paths and the movement time with respect to the selected minimum moving speed obtained for each individual movement path of the formed movement paths. And a total of the cycle time of the entire operation path is recorded, and from the record table, the entire operation path that has no interference with the work robot and that has the shortest cycle time and the selected one are selected. and determines a combination of the moving speed becomes the shortest, and wherein the creating a motion path data based on the previous SL sets combined.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an off-line teaching apparatus 10 according to an embodiment to which the operation route data creation method and apparatus for a work robot of the present invention is applied, and an articulated robot apparatus to which teaching data created by the off-line teaching apparatus 10 is applied. 12 shows a schematic configuration.
[0015]
The articulated robot apparatus 12 includes an end effector 22 such as a welding gun connected to a base 14 via a plurality of rotatable links 16, 18 and 20, and teaching data set in a robot control unit 24. Works according to. The articulated robot device 12 and the robot control unit 24 are arranged on the production line at the site.
[0016]
The offline teaching device 10 is configured by a computer. As shown in FIG. 2, the control unit 26 includes a CPU 28 that controls the entire offline teaching device 10, a ROM 30 and a RAM 32 that are storage units, and a hard disk. Operation path data of the articulated robot apparatus 12 is created, a hard disk 36 in which data is read and written by the drive 34, a recording medium drive 40 for reading and writing teaching data and the like to an external recording medium 38 such as a flexible disk and a compact disk. And a simulation circuit 44 that performs an operation simulation of the multi-joint robot apparatus 12 based on the generated operation path data. A display 46 for assisting teaching work by an operator, displaying a simulation image, and the like is connected to the control unit 26 via a drawing control circuit 48, and a keyboard 52 and a mouse 54 are connected via an interface 50. Connected.
[0017]
In the hard disk 36, an operation path creation program 56 for creating operation path data of the articulated robot apparatus 12, shape data 58 relating to the articulated robot apparatus 12, work objects and other equipment, and an articulated robot apparatus The robot specification data 60 including the motion specifications of each of the 12 axes, the parameter 62 which is the target data of the motion path data optimization process, the search condition data 64 set in relation to the parameter 62, and the motion path data Processing result data 66 generated at the time of creation is stored.
[0018]
Here, as the parameter 62, a moving speed parameter related to the moving speed of the multi-joint robot apparatus 12, a path parameter related to the operation path of the multi-joint robot apparatus 12 with respect to the relay point set in order to avoid interference, an articulated robot There is a movement reference parameter for selecting whether the movement speed of the end effector 22 of the apparatus 12 is used as a reference for optimization processing or whether the movement speed of each axis between the links 16, 18, and 20 is used as a reference for optimization processing. .
[0019]
The search condition data 64 related to the moving speed parameter sets an adjustment amount of the moving speed to be searched, and the search condition data 64 related to the route parameter is set in advance by an operator for the purpose of avoiding an interference object. The allowable range of the operation path centered on the relay point is set as radius data. The search condition data 64 related to the movement reference parameter is set as data for selecting whether the movement speed is based on the end effector 22 or each axis.
[0020]
As shown in FIG. 3, the operation path data creation circuit 42 includes a parameter combination generation unit 68 that generates a combination of possible parameters 62 based on the robot specification data 60, the parameters 62, and the search condition data 64, and the generated parameters. The motion plan creation unit 70 that creates a motion plan composed of motion commands of the articulated robot device 12 according to each combination of 62, and the motion route of the articulated robot device 12 is searched using the shape data 58 based on the motion plan. A movement path search section 72 that performs movement, a movement time calculation section 74 that calculates a movement time when the articulated robot apparatus 12 is moved according to the searched movement path, and an optimum parameter 62 that sets the movement time as the shortest time. Based on the determined optimum parameter determination unit 76 (movement speed selection unit, interference determination unit) and the determined parameter 62. And a movement path data generating unit 78 for creating route data.
[0021]
The offline teaching apparatus 10 of the present embodiment is basically configured as described above. Next, the operation will be described with reference to the flowcharts shown in FIGS. 4 and 5.
[0022]
Prior to the creation of the operation path data, the operation path creation program 56 is read from the hard disk 36 and loaded into the operation path data creation circuit 42. Next, the maximum speed, maximum acceleration, movable range, robot type, etc. of each axis of the multi-joint robot apparatus 12, which is the shape data 58 relating to the multi-joint robot apparatus 12, work object and other equipment, and robot specification data 60, etc. Data is read from the hard disk 36 (step S1). Also, the parameter 62 for performing the operation path data optimization process and the search condition data 64 set for the parameter 62 are read from the hard disk 36 (step S2).
[0023]
Next, the parameter combination generation unit 68 constituting the operation path data creation circuit 42 generates a combination of possible parameters 62 from the read parameters 62 and search condition data 64 (step S3). For example, a plurality of moving speeds are set according to the moving speed parameter and the search condition data 64, and a plurality of radii that are allowable ranges of the operation route centered on the relay point between the work points are set according to the route parameter and the search condition data 64. In accordance with the movement reference parameter and the search condition data 64, the case where the target of the moving speed is the end effector 22 and the case where each axis is used are set, and combinations of possible parameters 62 are generated from these.
[0024]
For the possible combinations of the parameters 62 generated as described above, the motion plan creation unit 70 creates a motion plan set as a motion command for the articulated robot apparatus 12 (step S4).
[0025]
Next, the motion path search unit 72, based on the motion path creation program 56, the shape data 58 read from the hard disk 36, and the position and orientation of the end effector 22 as work point data for the work object set by the operator. Thus, the operation path of the articulated robot device 12 is searched (step S5). For example, as shown in FIG. 6, the end effector 22 is searched for an operation path P1 for moving the end effector 22 to the set work point D1, and the end effector is moved to the relay point M avoiding the interference 80 generated from the work point D1 by the shape data 58. A search is made for an operation path P2 for moving 22, a search for an operation path P 3 for moving the end effector 22 from the relay point M to the next work point D 2, and a search for an operation path P 4 for extracting the end effector 22 from the work point D 2.
[0026]
After the movement path is searched, the optimum movement speed of the multi-joint robot apparatus 12 capable of performing the work in the shortest movement time is searched according to the movement plan for the combination of the parameters 62 created in the movement plan creation unit 70. (Step S6).
[0027]
In this case, the travel time calculation unit 74 reads the operation route searched by the operation route search unit 72 (step S6a), and first selects the operation route P1 with i = 1 (steps S6b and S6c). Next, the movement speed V of the articulated robot apparatus 12 is set to the maximum movement speed Vmax (step S6d), and the movement time on the operation path P1 is set by operating the articulated robot apparatus 12 on the operation path P1 according to the operation plan. Calculate (step S6e).
[0028]
Here, even if the movement speed V is set to the maximum movement speed Vmax, the articulated robot device 12 does not necessarily move to a desired work point in the shortest time. That is, as shown in FIG. 7, when the articulated robot apparatus 12 is set to the maximum movement speed Vmax, the movement time Tx at the movement speed Vx (<Vmax) is affected because of the influence of the vibration of the end effector 22 when stopped. Longer travel time Tmax may be required.
[0029]
Therefore, the moving speed V is decelerated by a predetermined amount using a predetermined adjustment amount Vc set as the search condition data 64 (V = V−Vc), and the moving time is calculated until the moving speed V reaches the lower limit value Vlow. Perform (Steps S6e, S6f, S6g).
[0030]
As described above, after calculating the movement time for each movement speed, the movement speed at which the shortest movement time is obtained is selected as the movement speed for the operation path P1 (step S6h).
[0031]
Similarly, i = i + 1 is set (step S6i), and the moving speed is selected for all the operation paths Pi (step S6j).
[0032]
Next, the presence or absence of interference at the selected moving speed is checked for each operation path (step S7). That is, for example, if another articulated robot 12 for abutment against the articulated robot 12, such as are provided, depending on the moving speed that has been selected, there is a case where the interference in the common operating region occurs . Therefore, as shown in FIG. 8, the parameter combination number related to the operation plan, the result of the interference check for the corresponding operation plan, and whether or not the operation plan is valid are set based on the result of the interference check. A recording table including the flag and the cycle time when moving between the respective work points is created (step S8). The cycle time is obtained by adding the movement time obtained in each operation path in step S6j.
[0033]
Similarly, the movement speed is searched for each operation plan until the movement speed search for all combinations of the parameters 62 is completed (step S9).
[0034]
The moving time is set according to the search condition data 64 of the movement reference parameter, which is the parameter 62, when the moving speed V is set for the end effector 22 of the articulated robot apparatus 12, and when the moving speed V is set for each axis. Can be calculated respectively.
[0035]
Further, as shown in FIG. 6, the parameter 62 includes a route parameter for setting an allowable range including a radius r indicated by a dotted line at the relay point M for avoiding the interference 80. By setting the route parameter, for example, after the end effector 22 reaches the allowable range from the operation route P2, it can be set to move to the operation route P3 without passing through the relay point M. In this case, as indicated by the alternate long and short dash line, it is not necessary for the end effector 22 to accurately reach the relay point M, and the moving speed can be set higher accordingly. Therefore, the travel time varies depending on the route parameter.
[0036]
As described above, after the movement speed for each combination of the parameters 62 is searched and the recording table shown in FIG. 8 is created, the combination of the parameters 62 that has no interference in the operation path and has the shortest cycle time is obtained. Determine (step S10). In FIG. 8, parameter combination number 2 is selected.
[0037]
Finally, motion path data is created based on the optimum combination of parameters including the optimum movement speed in each motion path determined in step S10 (step S11).
[0038]
After the motion path data is set in the hard disk 36 as the processing result data 66, the simulation circuit 44 performs a motion simulation of the articulated robot apparatus 12 using the motion path data. The motion path data whose motion has been confirmed by the simulation is recorded on the external recording medium 38 via the recording medium drive 40, and then downloaded to the robot control unit 24 as teaching data and used for controlling the articulated robot device 12. The
[0039]
【The invention's effect】
As described above, according to the present invention, it is possible to automatically set an optimum movement speed that can minimize the movement time of the work robot with respect to the work point, regardless of the operator's work, thereby shortening the cycle time. be able to.
[0040]
Further, when searching for the moving speed, it is possible to determine an effective moving speed that can minimize the moving time by checking the presence or absence of interference due to the difference in moving speed. Therefore, highly reliable operation path data can be obtained.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an off-line teaching device and an articulated robot device according to an embodiment.
FIG. 2 is a circuit configuration diagram of the off-line teaching apparatus of the present embodiment.
FIG. 3 is a block diagram of an operation path data creation circuit in the off-line teaching device of the present embodiment.
FIG. 4 is a flowchart of an operation path data creation method in the offline teaching apparatus of the present embodiment.
FIG. 5 is a flowchart of an operation path data creation method in the offline teaching apparatus of the present embodiment.
FIG. 6 is an explanatory diagram of an operation path in the offline teaching apparatus according to the embodiment.
FIG. 7 is an explanatory diagram of a relationship between a moving speed and a moving time in the offline teaching apparatus of the present embodiment.
FIG. 8 is an explanatory diagram of a recording table created in the offline teaching apparatus of the present embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Offline teaching apparatus 12 ... Articulated robot apparatus 24 ... Robot control part 26 ... Control part 36 ... Hard disk 42 ... Motion path data creation circuit 44 ... Simulation circuit 56 ... Motion path creation program 58 ... Shape data 60 ... Robot specification data 62 ... parameter 64 ... search condition data 66 ... processing result data 68 ... parameter combination generation unit 70 ... action plan creation part 72 ... action route search part 74 ... travel time calculation part 76 ... optimum parameter determination part 78 ... action path data creation part 80 ... interference

Claims (2)

In a method for creating motion path data including the movement speed of a work robot with respect to a plurality of work points,
Set the allowable range in the relay point for avoiding interference between the work points constituting a plurality of individual operation path constituting the entire operation path, entire operation path including the allowable range of the working robot for said relay point Forming a plurality of
A plurality of movement speeds are set for the work robot moving to the work point, and the movement time to the work point is calculated for each movement speed for each individual movement path of the entire movement paths formed. Steps,
Selecting the movement speed at which the movement time is the shortest for each individual movement path of the entire movement paths formed ;
Determining the presence or absence of interference of the work robot operating at the selected moving speed for each individual movement path of the entire movement path formed ;
Total travel time for the mobile speed to be determined by the result as the shortest selected for each individual path of movement of each entire operation path in which the formed of the presence or absence of interference of the working robot for each whole each operation route of the formed Creating a recording table that records the cycle time of the entire operation path ;
Wherein the record table, the work interference with the robot without and the cycle time determines the motion path and the entire combination of the moving speed to be the selected shortest shortest, operation based on the previous SL sets combined Creating route data;
With
The step of calculating the movement time is based on the time required for the work robot to reach the work point and the time required for the work robot to stop oscillating after reaching the work point. And calculating the travel time of the work robot. In an apparatus for creating motion path data including the movement speed of a work robot with respect to a plurality of work points,
Set the allowable range in the relay point for avoiding interference between the work points constituting a plurality of individual operation path constituting the entire operation path, entire operation path including the allowable range of the working robot relative to the working point A plurality of motion path search units,
A plurality of movement speeds are set for the work robot that moves to the work point, and the movement time to the work point is calculated for each movement speed for each individual movement path of the entire movement path that is formed. Travel time calculator,
A moving speed selecting unit that selects the moving speed at which the moving time is the shortest for each individual operation path of the entire formed operation path ;
An interference determination unit that determines the presence or absence of interference of the work robot that operates at the selected moving speed for each of the formed individual operation paths.
With
The movement time calculation unit is configured to perform the movement based on a time required for the work robot to reach the work point and a time required for the work robot to stop oscillating after the work robot reaches the work point. Calculate the time,
The result of the presence / absence of interference of the work robot determined for each of the formed movement paths and the movement time with respect to the selected minimum moving speed obtained for each individual movement path of the formed movement paths. Make a record table for recording with said motion path overall cycle time which is the sum of the the recording table, wherein there is no interference with the work robot, and the cycle time is entire operating path shortest and ing and the selection It was to determine the combination of the moving speed of the shortest, movement path data generating device for a working robot, characterized in that to create a motion path data based on the previous SL sets combined.

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