JP5198930B2 - Robot movement control device and movement control method for reducing cycle time - Google Patents

Description

  The present invention relates to a movement control device and a movement control method for an industrial robot (hereinafter simply referred to as a robot).

  Various techniques have been proposed for shortening the robot operation time, that is, the cycle time. For example, in Patent Document 1, in a robot acceleration / deceleration time constant control system that controls the operation of a robot while determining an acceleration / deceleration time constant of a servo motor to an optimum value for each block, an arrival speed is obtained from a movement amount of the block, The servo motor output torque is obtained from the reached speed, the static load torque is subtracted from the output torque to obtain the acceleration torque and the deceleration torque, and the load inertia of the acceleration torque, the deceleration torque, and the current position and the target position of the servo motor. Thus, there is disclosed an acceleration / deceleration time constant control system that obtains acceleration during acceleration and deceleration, and individually determines an acceleration time constant and a deceleration time constant from the acceleration during acceleration and deceleration.

  In Patent Document 2, a position of each joint when the hand of an articulated robot is moved to a target position is set as a target value, and each joint is driven so as to be the target value. In the method of controlling the driving of the articulated robot, the operation time of each joint is set for each joint, an operation program is created so that the operation end times of the joints do not overlap, and each joint is assigned based on the operation program. A drive control method for driving is disclosed.

  Further, in Patent Document 3, when the operation time becomes shorter when the maximum speed is lowered, the maximum speed of each axis is adjusted based on the allowable maximum value of the driving torque or the acting torque of each axis, and the operation is performed. A robot control device aimed at reducing time is disclosed.

  FIG. 1 is a block diagram of a robot control apparatus 100 for performing conventional movement control. The control device 100 includes a program storage unit 102 such as a non-volatile memory that stores a start point position, an end point position, a command speed, an interpolation format, and the like of an operation sentence in a taught program, and a mass, a gravity center position, and a gravity center And a parameter storage unit 104 that stores parameters such as surrounding inertia.

  The control device 100 also includes an interpolation unit 106 and a motor control unit 108. The interpolation unit 106 is based on information such as a start point position, an end point position, a moving speed, and an interpolation format of an operation sentence in the program when the program is reproduced. Create a speed command for each interpolation cycle. This is usually a step-like speed command, and if this is used as it is as a command to the motor control unit 108, the robot mechanism unit may vibrate greatly. In order to prevent this, a filter 110 such as a moving average filter is provided between the interpolation unit 106 and the motor control unit 108.

  In addition, the control device 100 includes an inertia calculation unit 112 that calculates the inertia viewed from the motor of each axis of the robot at the current position and orientation of the robot mechanism unit 150, the stored contents of the parameter storage unit 104, and the inertia calculated by the inertia calculation unit 112. And a time constant calculation unit 114 that calculates a time constant based on the time constant. By passing the time constant obtained by the time constant calculation unit 114 through the filter 110, a smooth speed command can be obtained.

FIG. 2 is a diagram for explaining processing by the movement control device having the configuration shown in FIG. First, as shown in FIG. 2A, the moving distance L (square area) is determined from the start position and end position in a certain operation, and the moving time initial value M ₀ is obtained by dividing the moving distance L by the command speed V _0. Desired. However, when a step-like speed command as shown in FIG. 2 (a) is actually given, the robot mechanism part may vibrate greatly, so the processing for setting the acceleration region and the deceleration region as shown in FIG. 2 (b) is performed. . First, the inertia seen from the motor of each axis at the current position and orientation is calculated, and the acceleration a is obtained by dividing the maximum torque that can be output by the motor by the inertia. By dividing the command speed initial value V ₀ by the acceleration a, the time constant initial value F ₀ is obtained. As a tendency, in a position and orientation with a large inertia, the acceleration a becomes small, so the time constant becomes long, and the cycle time T that is the sum of the moving time initial value M ₀ and the time constant F ₀ also becomes long.

Further, even in a position and orientation where the inertia can be increased and the acceleration can be increased, the above acceleration region and deceleration region are set when the moving distance L is relatively short with respect to the command speed V ₀ as shown in FIG. When the process is performed, as shown in FIG. 3B, an operation pattern in which the speed of the robot does not reach the command speed V ₀ is created within the movement time initial value M ₀ . That is, in the case of FIG. 3, acceleration is performed at the acceleration a during the movement time M ₀ , and the operation is decelerated after moving at a constant speed at a speed lower than V ₀ .

JP-A-6-337708 JP-A-7-295615 JP 11-259108 A

When the moving time initial value M ₀ is shorter than the time constant initial value F _{0 as} shown in FIG. 3B, the command speed output by the moving average filter 110 does not reach the command speed initial value V ₀ . In such a case, the cycle time becomes shorter when only the acceleration / deceleration operation is performed as shown in FIG. In the case of FIG. 3C, the maximum speed Vs that can be reached without changing the acceleration a (= V ₀ / F ₀ ) is expressed by the following equation (1).
Vs = V ₀ · (M ₀ / F ₀ ) ^1/2 (1)

A new movement time Ms is obtained by the following equation (2) using the command speed Vs and the movement distance L. It is obvious that the time constant Fs at this time is equal to Ms.
Ms = L / Vs (2)

As shown in FIG. 3 (c), as a method of determining whether to perform only acceleration / deceleration operations, a teaching worker designates an operation only for acceleration / deceleration as an arbitrary operation when creating a program (hereinafter referred to as a pass command). If the product of the acceleration a and the moving time initial value M ₀ is less than the command speed V ₀ , the pass command is automatically added, or the teaching speed is automatically or manually set by the operator. A method of changing to the speed Vs is conceivable.

  Here, the operation of the robot is generally controlled to perform a series of operations by sequentially performing individual operations as shown in FIG. 2 or FIG. As described above, for each operation, control is performed to minimize the cycle time (specifically, the sum of the travel time and the time constant described above) based on the start position, end position, speed command, and the like in each operation. Is called. However, in order to shorten the operation time of a series of operations or smooth the movement of the robot, each operation often starts the next operation before the previous operation is completely completed. In such a case, the time constant of the next operation is set in order to prevent the next operation from being completed before the previous operation is completed and the robot operation to differ from the operation intended by the operator. A process of setting a lower limit value corresponding to the operation condition of the previous operation as the minimum value (so-called clamping process) may be performed.

  In a specific clamping process, when the time constant in the current operation is shorter than the time constant in the previous operation, the time constant in the previous operation is used in the current operation. That is, the time constant of one operation is set as the lower limit value Ft of the time constant of the next operation. On the other hand, when the current time constant is longer than the previous time constant, the current time constant becomes the lower limit value Ft of the next time constant. In addition, it is not necessary to perform the clamping process in the single operation that is not continuous or the first operation among the continuous operations. The clamping process is also necessary in the case of FIG. 2B or FIG. 3B in which the initial value of the movement time and the time constant are different.

For example, FIG. 4 shows an example in which the clamping process is performed on the operation pattern of FIG. In this case, since the previous time constant Fc is longer than the current time constant F ₀ , the time constant is clamped (the lower limit value of the time constant is set to Fc) as shown in FIG. It is limited to Vs considerably lower than ₀ . As a result, the operation has a long cycle time as a whole. FIG. 5 shows an example in which the clamping process is performed on the operation pattern of FIG. In this case is changed to the constant Fc time time constant Fs is the last, also extend from M ₀ to Mc moving time with it, as shown in FIG. 5 (b), a long operation of the cycle time as a whole.

  In both the cases of FIGS. 4 and 5, the cycle time is increased by the clamping process. In this case, the entire cycle time may be shortened if the above-mentioned pass instruction is not added. In this case, the operator must determine whether or not to add a pass instruction for each operation and create a program. I must. In actual practice, the command speed is often determined by trial and error to shorten the cycle time, but this work is quite troublesome.

  Therefore, an object of the present invention is to provide a robot movement control device and a movement control method capable of efficiently shortening the cycle time of the robot without troublesome trial and error.

In order to achieve the above object, according to the first aspect of the present invention, a sequence of operation commands for performing an operation from a stationary state of a robot to a next stationary state during execution of the operational program is provided. Read, perform acceleration / deceleration filter processing for each operation command, convert the stepped speed command into a speed command including an acceleration unit and a deceleration unit, and sequentially output the converted speed command, the series of operation commands A movement control method for a robot that executes an operation according to claim 1, wherein the first movement command of the series of movement commands includes a movement distance, a command speed initial value, and a movement time initial value based on the operation program. A step of generating a speed command, and a step of obtaining a time constant initial value as a final time constant for the first operation command based on a predetermined algorithm. And a stepwise speed command including a movement distance, a command speed initial value, and a movement time initial value based on the operation program for the second and subsequent operation commands of the series of operation commands; Obtaining a time constant initial value for the second and subsequent operation commands based on a predetermined algorithm, and when the time constant initial value is shorter than the final time constant in the previous operation command, the previous operation and performing a clamping process a final time constant as the final time constant of this operation in order to compare the cycle time after the clamping process in the cycle time and the present operating instructions in the previous operation instruction, this if: cycle time cycle time after clamping is in the previous operation command in the operation instruction, the current dynamic Time constant initial value in travel time initial value and the command speed initial value of each final time constant, while adopting as a moving time and the command speed, and the lower limit value of the time constant of the final time constant following operations a step of, by comparing the cycle time after the clamping process in the cycle time and the present operating instructions in the previous operation instruction, when the cycle time after the clamping in the current operation command is longer than the cycle time in the previous operation command the front SL travel time initial value, the time to re-compute the final moving time based on the constant initial value and the final time constant, further based on the final moving time and the moving distance Recalculating the final command speed, and the acceleration / deceleration speed based on the final command speed, the final time constant, and the final travel time. There is provided a robot movement control method characterized by comprising a step of executing a filter process and a step of using the output of the filter process for motor control.

  According to a second aspect of the present invention, in the robot movement control method according to the first aspect of the present invention, a step of performing an acceleration / deceleration filter process on the stepped speed command to obtain a time constant initial value, and the previous operation command The moving time initial value is compared with the time constant initial value during the step of setting the final time constant in the operation as the final time constant of this operation, and the moving time initial value is the time constant initial value. In a shorter case, a robot movement control method is provided, which further includes a step of converting a current operation command to perform a movement operation only for acceleration / deceleration.

  According to a third aspect of the present invention, in the robot movement control method according to the first or second aspect, an acceleration / deceleration filter process using a plurality of types of acceleration / deceleration filters is performed for each operation command, and the cycle time is Provided is a robot movement control method further comprising a step of using a processing result that minimizes for motor control.

  The invention according to claim 4 is the robot movement control method according to any one of claims 1 to 3, wherein the acceleration / deceleration filter processing includes a plurality of acceleration / deceleration filter processing connected in series, When the time constant of one acceleration / deceleration filter process is shorter than the final time constant of the previous operation command, the robot movement control further includes a step of adopting the time constant of the previous operation command as the current final time constant Provide a method.

According to the fifth aspect of the present invention, during the execution of the motion program, a series of motion commands for starting the movement from the stationary state of the robot to the next stationary state is read and added to each motion command. Movement of a robot that performs a deceleration filter process, converts a stepped speed command into a speed command including an acceleration unit and a deceleration unit, and sequentially outputs the converted speed command to execute an operation based on the series of operation commands. An interpolation unit for creating a step-like speed command including a moving distance, a command speed initial value and a moving time initial value based on the operation program; and the first operation command based on a predetermined algorithm. The initial value of the time constant is determined as the final time constant, and the second and subsequent operation instructions of the series of operation instructions are assigned to a predetermined algorithm. Accordingly, a time constant calculation unit for obtaining a time constant initial value for the second and subsequent operation instructions, and when the time constant initial value is shorter than a final time constant in the previous operation instruction, When the time constant clamp part that performs clamping processing with the final time constant as the final time constant of the current operation and the cycle time after the clamp processing in the current operation command is longer than the cycle time in the previous operation command, A movement time recalculation unit that recalculates the final movement time based on the movement time initial value, the time constant initial value, and the final time constant, and the cycle time after the clamping process in the current operation command is the previous time When the movement time is longer than the cycle time in the operation command, the final movement time and the movement distance calculated by the movement time recalculation unit And command speed recalculation unit to recalculate the decree speed,
A moving average filter that executes acceleration / deceleration filter processing based on the final command speed, the final time constant, and the final moving time, and an output of acceleration / deceleration filter processing by the moving average filter for motor control There is provided a movement control device for a robot characterized by having a motor control unit to be used.

  According to a sixth aspect of the present invention, in the movement control device for a robot according to the fifth aspect, the movement time initial value is compared with the time constant initial value, and the movement time initial value is greater than the time constant initial value. Provided is a robot movement control method that further includes a path command processing unit that converts a current motion command so as to perform a motion motion of only acceleration / deceleration when the operation command is short.

  According to a seventh aspect of the present invention, there is provided the robot movement control device according to the fifth or sixth aspect, wherein the robot has a plurality of types of acceleration / deceleration filters for performing acceleration / deceleration filter processing for each operation command. Provide a control method.

  An eighth aspect of the present invention provides the robot movement control device according to any one of the fifth to seventh aspects, wherein the robot movement control method includes a plurality of acceleration / deceleration filters connected in series.

  According to the robot movement control method or the movement control apparatus of the present invention, it is possible to prevent the cycle time from being prolonged by dragging the acceleration / deceleration time constant of the previous operation in a series of operations of the robot. The cycle time can be shortened without having to do this.

  When the moving time initial value is shorter than the time constant initial value, the cycle time can be further shortened by converting the current operation command so as to perform the moving operation of only acceleration / deceleration.

  By performing acceleration / deceleration filter processing using multiple types of acceleration / deceleration filters for each operation command, the processing result that minimizes the cycle time can be selected from multiple processing results. Can be shortened.

  By performing filter processing using a plurality of acceleration / deceleration filters connected in series, when the time constant of at least one acceleration / deceleration filter processing is shorter than the final time constant of the previous operation command, The constant can be the final time constant of this time, which reliably prevents the next operation from being completed before the one operation is completed.

  FIG. 6 is a block diagram of a movement control device 10 for performing movement control of a robot according to the present invention. During execution of the robot operation program, the control device 10 reads a series of operation commands for starting the movement from the stationary state of the robot to the next stationary state, and performs acceleration / deceleration filtering on each operation command. Processing is performed, the rectangular speed command is converted into a speed command including an acceleration region and a deceleration region, and the converted speed command is sequentially output to cause the robot to execute an operation based on the series of operation commands. . Specifically, the control device 10 includes a program storage unit 12 such as a non-volatile memory that stores a start point position, an end point position, a command speed, an interpolation format, and the like of an action sentence in the taught program, a mass of the robot mechanism unit, And a parameter storage unit 14 for storing parameters such as the gravity center position and inertia around the gravity center.

  The control device 10 also includes an interpolation unit 16 that creates a speed command for each interpolation period based on information such as the start point position, end point position, movement speed, and interpolation format of an operation statement in the program, and a robot. And a motor control unit 18 that sends a movement command to each axis motor of the mechanism unit 50. Furthermore, the control device 10 includes an inertia calculation unit 22 that calculates the inertia viewed from the motor of each axis of the robot at the current position and orientation of the robot mechanism unit 50, and the storage content of the parameter storage unit 14 and the inertia calculated by the inertia calculation unit 22. And a time constant calculator 24 for calculating a time constant initial value based on the above. There are various algorithms for obtaining the initial value of the time constant. Here, the acceleration is obtained by dividing the maximum torque that the motor can output by the inertia, and the time constant is obtained by dividing the initial value of the command speed by this acceleration. Assume that initial values are obtained.

  The above components may be the same as those of the control device 100. The control device 10 according to the present invention further includes a path command processing unit 26, a moving time recalculating unit 28, a command speed recalculating unit 30, a time constant clamping unit 32, a first moving average filter 34, and a second moving average filter 36. Have. Hereinafter, the operation of each element will be described with reference to FIGS.

FIG. 7 is a flowchart illustrating an example of processing of a robot movement control method using the movement control device 10. First, in step S1, the time constant calculation unit 24 reads the parameters of the robot mechanism unit 50 read from the parameter storage unit 14 and the inertia around the motor obtained by the inertia calculation unit 22 from the current position and orientation of the robot mechanism unit 50. A time constant initial value F ₀ suitable for the inertia is calculated.

Next, in step S <b> 2, the path command processing unit 26 reads the movement time initial value M ₀ and the command speed initial value V ₀ from the interpolation unit 16. Here, as described above with reference to FIG. 3, when the movement time initial value M ₀ is less than the time constant F ₀ (M ₀ <F ₀ ), the pass command processing unit 26 adds a pass command and adds FIG. The process of setting the operation pattern only for acceleration / deceleration as in (c) is performed (steps S3 and S4). In the present embodiment, even if the teaching worker does not add a pass command, when M ₀ <F ₀ , the process for performing only the acceleration / deceleration operation is performed. The time constant after this pass instruction processing is defined as Fs. Further, the moving time Ms and the command speed Vs after the pass command processing are calculated from the time constant Fs.

Next, in step S5, as shown in FIG. 5 (b) or FIG. 8 (b), the time constant clamping unit 32 performs a clamping process based on the previous time constant on the time constant Fs or F ₀ , and moves time Mc, time constant Fc, and command speed Vc are calculated. On the other hand, when the moving time initial value M ₀ is not less than the time constant F ₀ (M ₀ ≧ F ₀ ) as shown in FIG. 2, the operation pattern shown in FIG. The time constant clamping unit 32 performs the clamping process based on the time constant of the immediately preceding operation as described above. At the same time, the time constant clamping unit 32 performs an experiment to prevent vibration unique to the mechanism unit and adjusts a threshold value (for example, a parameter storage unit). 14) may be performed simultaneously. That is, when the initial value of the time constant is shorter than the experimentally adjusted threshold value, the threshold value is set as the time constant of the current operation.

The movement time recalculation unit 28 uses the movement time Ms or the movement time initial value M ₀ after the pass command is added, the cycle time (Ms + Fc) or (M ₀ + Fc), and the cycle time (Mc + Fc) after the clamping process. If the cycle time is not longer after the clamping process, Mc, Fc and Vc are used as they are as the final travel time Mf, time constant Ff and command speed Vf (steps S6 and S7). On the other hand, if the cycle time (Ms + Fc) or (M ₀ + Fc) using the movement time after the pass command is added or the initial value of the movement time is shorter than the cycle time (Mc + Fc) after the clamping process, the movement time and the command speed Is recalculated to obtain a new travel time Mnew and a command speed Vnew (step S8). Specifically, as shown in FIG. 8C or FIG. 9C, Mnew has a clamped time constant Fc, performs acceleration / deceleration at acceleration a, and the entire moving distance is a predetermined value L. To be equal to As an example, Mnew can be obtained using equations (3-1) to (5) described below.

First, when the robot speed reaches the command speed V ₀ , the entire moving distance L is expressed by the following equation (3-1).
L = V ₀ · M ₀ = a · F ₀ · M ₀ (3-1)
On the other hand, when the speed of the robot does not reach the command speed V ₀ , the entire moving distance L is expressed by the following equation (3-2). Vact is a speed at which the robot actually reaches.
L = Vact · F ₀ = a · F ₀ · M ₀ (3-2)

When the time constant Fc after the clamping process is used, the following equations (4-1) and (4-2) are established for each of cases where the command speed is reached and where the command speed is not reached.
L = Vnew / Mnew = a / Fc / Mnew (4-1)
L = Vact · Fc = a · Fc · Mnew (4-2)

From equations (3-1) to (4-2), the new travel time Mnew is expressed by the following equation (5) in both cases where the command speed is reached and where the command speed is not reached.
_{Mnew = M 0 · F 0 /} Fc (5)

On the other hand, the command speed recalculation unit 30 calculates a new command speed Vnew by the following equation (6) using Mnew.
_{Vnew = M 0 · V 0 /} Mnew (6)
The movement time Mnew, the command speed Vnew and the time constant Fc thus obtained become the final movement time Mf, the command speed Vf and the time constant Ff (step S9).

  When the final travel time Mf, the command speed Vf, and the time constant Ff are determined in step S7 or S9, the first moving average filter 34 performs acceleration / deceleration filter processing in step S10. The operation pattern after the acceleration / deceleration filter processing is as shown in FIG. 10 (a) if displayed in an analog manner, but in detail, as shown in FIG. 10 (b), a stepped constant speed command is appropriately applied. This is performed continuously in increments of time, and a smooth robot operation with little vibration can be realized.

  As shown in FIG. 6, the control device 10 makes the speed command smoother in series with the first moving average filter 34 that performs acceleration / deceleration filter processing based on the finally determined moving time, command speed, and time constant. The second moving average filter 36 that performs filter processing for suppressing vibration may be provided. The time constant of the second moving average filter 36 is constant, and the process of changing the time constant as the process performed by the first moving average filter 34 is not performed by the second moving average filter. Alternatively, the second moving average filter also performs the process of changing the time constant, and when the time constant changed in at least one of the first and second moving average filters is smaller than the time constant of the previous operation, It is also possible to clamp the time constant of the operation to the time constant of the previous operation. Further, three or more moving average filters may be used by adding a moving average filter in series. Furthermore, a filter other than a moving average filter such as an exponential filter can be used instead.

  As another aspect, the first moving average filter 34 and one or more different types of moving average filters are used in parallel, and the process shown in FIG. 7 is performed for each of the different moving average filters, and a plurality of obtained results are obtained. Of these, the one having the shortest cycle time (the sum of the final travel time and the time constant) can be adopted.

It is a block diagram of the movement control apparatus of the robot which concerns on a prior art. (A) It is a figure which shows the example which calculates | requires a movement time initial value based on a predetermined | prescribed movement distance and instruction | command speed, (b) It is a figure which shows the example of an operation pattern obtained by performing an acceleration / deceleration filter process to (a). . (A) It is a figure similar to FIG. 2 (a), and is a figure which shows the case where a movement distance is short with respect to instruction | command speed, (b) The figure which shows the example of an operation pattern obtained by performing an acceleration / deceleration filter process to (a) And (c) is a diagram showing an example in which the operation pattern of (b) is converted into an operation pattern of only acceleration / deceleration operation. (A) It is a figure similar to FIG.3 (b), It is a figure which shows the example of an operation | movement pattern obtained by giving a clamp process to (b) (a). (A) It is a figure similar to FIG.3 (c), and is a figure which shows the example of an operation | movement pattern obtained by giving a clamp process to (b) (a). It is a block diagram of the movement control apparatus of the robot which concerns on this invention. It is a flowchart which shows an example of the flow of the movement control method using the movement control apparatus which concerns on this invention. (A) It is a figure similar to FIG. 3 (a), (b) It is a figure similar to FIG. 5 (b), and the operation pattern obtained by performing recalculation processing on the operation pattern of (c) and (b) It is a figure which shows an example. (A) It is a figure similar to Fig.2 (a), (b) It is a figure which shows the example of an operation pattern obtained by performing a clamp process to (a), (c) It is a figure recalculated to the operation pattern of (b) It is a figure which shows the example of an operation pattern obtained by giving a process. (A) It is a figure which shows the operation pattern obtained by carrying out the acceleration / deceleration filter process of the conditions finally obtained, (b) It is a figure which shows the example which described the operation pattern of (a) in detail. is there.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Movement control apparatus 12 Program memory | storage part 14 Parameter memory | storage part 16 Interpolation part 18 Motor control part 22 Inertia calculation part 24 Time constant calculation part 26 Path command processing part 28 Travel time recalculation part 30 Command speed recalculation part 32 Time constant clamp part 34 1st moving average filter 36 2nd moving average filter 50 Robot mechanism part

Claims (8)

During operation program execution, a series of operation commands for starting the movement from the stationary state of the robot to the next stationary state is read, acceleration / deceleration filter processing is performed for each operation command, and stepped A robot movement control method for converting a speed command into a speed command including an accelerating unit and a decelerating unit, and sequentially executing the converted speed command to execute an operation based on the series of operation commands,
Creating a step-like speed command including a movement distance, a command speed initial value and a movement time initial value based on the operation program for the first operation command of the series of operation commands;
Obtaining a time constant initial value as a final time constant for the first operation instruction based on a predetermined algorithm;
For the second and subsequent operation commands in the series of operation commands,
Based on the operation program, creating a step-like speed command including a moving distance, a command speed initial value, and a moving time initial value;
Obtaining a time constant initial value for the second and subsequent operation instructions based on a predetermined algorithm;
When the initial value of the time constant is shorter than the final time constant in the previous operation instruction , performing a clamping process using the final time constant in the previous operation instruction as the final time constant of the current operation; ,
Compare the cycle time of the previous operation command with the cycle time of the current operation command after clamping. If the cycle time of the current operation command after clamping is less than or equal to the cycle time of the previous operation command, In this operation, the initial value of the time constant, the initial value of the moving time and the initial value of the command speed are adopted as the final time constant, the moving time and the command speed, respectively, and the final time constant is used as the lower limit of the time constant of the next operation. A value step;
Compare the cycle time of the previous operation command with the cycle time of the current operation command after clamping. If the cycle time of the current operation command after clamping is longer than the cycle time of the previous operation command , The final travel time is recalculated based on the initial travel time value, the initial time constant value, and the final time constant, and the final command is based on the final travel time and the travel distance. Recalculating the speed,
Executing acceleration / deceleration filter processing based on the final command speed, the final time constant and the final travel time;
Using the output of the filtering process for motor control;
A robot movement control method comprising: Between the step of performing acceleration / deceleration filter processing on the stepped speed command to obtain a time constant initial value and the step of setting the final time constant in the previous operation command as the final time constant of the current operation ,
A step of comparing the moving time initial value with the time constant initial value, and converting the current operation command to perform a moving operation only for acceleration / deceleration when the moving time initial value is shorter than the time constant initial value. The robot movement control method according to claim 1, further comprising:   3. The method according to claim 1, further comprising a step of performing acceleration / deceleration filter processing using a plurality of types of acceleration / deceleration filters for each operation command, and using a processing result having a minimum cycle time for motor control. Robot movement control method.   The acceleration / deceleration filter process includes a plurality of acceleration / deceleration filter processes connected in series, and when the time constant of at least one acceleration / deceleration filter process is shorter than the final time constant of the previous operation instruction, The robot movement control method according to claim 1, further comprising a step of adopting the time constant as the final time constant of this time. During operation program execution, a series of operation commands for starting the movement from the stationary state of the robot to the next stationary state is read, acceleration / deceleration filter processing is performed for each operation command, and stepped A robot movement control device that converts a speed command into a speed command including an acceleration unit and a deceleration unit, and sequentially executes the converted speed command to execute an operation based on the series of operation commands,
An interpolation unit that creates a step-like speed command including a moving distance, a command speed initial value, and a moving time initial value based on the operation program;
A time constant initial value is obtained as a final time constant for the first operation instruction based on a predetermined algorithm, and the second and subsequent operation instructions in the series of operation instructions are determined based on a predetermined algorithm. A time constant calculation unit for obtaining a time constant initial value for subsequent operation instructions;
When the time constant initial value is shorter than the final time constant in the previous operation instruction, the time constant for performing clamp processing with the final time constant in the previous operation instruction as the final time constant of the current operation A clamp part;
When the cycle time after the clamping process in the current operation command is longer than the cycle time in the previous operation command, the final movement time is based on the initial value of the movement time, the initial value of the time constant, and the final time constant. A travel time recalculation unit for recalculating
When the cycle time after clamping in the current operation command is longer than the cycle time in the previous operation command, the final command speed is calculated based on the final movement time and the movement distance calculated by the movement time recalculation unit. A command speed recalculator that recalculates
A moving average filter that executes acceleration / deceleration filter processing based on the final command speed, the final time constant, and the final movement time;
A motor control unit that uses the output of acceleration / deceleration filter processing by the moving average filter for motor control;
A robot movement control device comprising:   A path for comparing the moving time initial value with the time constant initial value, and converting the current operation command to perform a moving operation only for acceleration / deceleration when the moving time initial value is shorter than the time constant initial value. The robot movement control device according to claim 1, further comprising a command processing unit.   The robot movement control device according to claim 5 or 6, comprising a plurality of types of acceleration / deceleration filters that respectively perform acceleration / deceleration filter processing for each operation command.   The robot movement control device according to claim 5, comprising a plurality of acceleration / deceleration filters connected in series.

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