JPH0934522A - Robot control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To trace a proper moving path of a robot with a prescribed limit speed without waste of time by periodically inputting the shift value of every shaft to describe the interpolation points generated in an interpolation control mode, periodically carrying out the processing related to the limit speed of every shaft, and periodically outputting the shift value of every shaft to the servo control system of every shaft in order to keep the limit speed of every shaft. SOLUTION: The shift value of every shaft that is outputted to a servo control system in every processing cycle is defined as an un-outputted component with no conflict with the limit speed of every shaft (1), with observance of the cooperation conditions to all shafts (2) and with observation of the limit speed of every shaft (3). Such shift value of every shaft is outputted with preference in the subsequent processing cycles. If the shift value is directly sent to the servo control system while the increment of θi exceeds the limit value M by δi in a section P1P2, the conflict is caused with the limit speed of a shaft (i). Under such conditions, the limit value M is outputted as the shift value of the shaft (i) in a processing cycle where the shift value of the section P1P2 is received. As a result, the shift target point of P1 is not set at P2 but at Q2 and both δi and δj are treated in the subsequent processing cycles.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling an industrial robot (hereinafter, simply referred to as "robot"), and more specifically, it follows a proper moving route without wasting time while keeping a speed limit. The present invention relates to a control method of a robot that is capable of performing.

[0002]

2. Description of the Related Art When a robot executes a taught program, it is necessary to perform control so that the robot operates while keeping the taught locus and speed. However, there is a limit to the moving speed of each axis of the robot (the angular speed of turning in the case of a turning axis, the linear moving speed in the case of a direct-acting axis), which comes from the maximum rotation speed of the motor that drives the axis. Therefore, there may be a case where it is impossible to operate while protecting both the taught trajectory and speed.

In such a case, in the conventional method, the movement amount of each axis designated through interpolation calculation at the time of route planning
The axis was limited so as not to require a speed exceeding the speed limit. As a result, with respect to the axis whose movement amount is limited, the movement amount necessary for realizing the taught route is not passed to the servo controlling the axis, and the deterioration of the route accuracy cannot be avoided.

Generally, when the override is specified to be low, the motor is not required to rotate at a high speed, so that such a phenomenon is unlikely to occur. That is, when a relatively high override is specified and the regeneration operation is performed,
There are many cases in which the route accuracy is greatly deteriorated and an interference accident occurs.

Therefore, conventionally, it is necessary to start a comparatively low override, repeat the trial regeneration operation (test run) while gradually increasing the override, and make sure that the route does not deteriorate beyond the allowable range. Met.

As a method of avoiding the deterioration of the route, there is a method of rewriting the speed designated by a program in addition to the method of reducing the override. In either case, the operation speed of the robot is also applied to the path portion which does not need the speed limitation. Will decrease and cycle time will become longer. There is also a method of changing the route for a route portion (for example, a corner portion) that causes deterioration of the route, but a re-teaching work for that is required for the user.

[0007]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to take a corrected movement path only for a portion that violates the speed limit of each axis and to quickly return to the teaching path after passing through that portion. It is to provide a control method of a robot that enables path movement.

More specifically, according to the present invention, even when a program is executed due to a high override (eg, 100%), a conflict with a speed limit condition occurs on any axis, the conflict occurs. It is intended to provide a control method in which a locus approximately the same as when taught with a low override for a portion to be realized is realized. Further, the present invention shortens the cycle time within the range of the robot capability, even for a program in which any axis may conflict with the speed limiting condition when the program is executed with a high override,
The object is to avoid requiring the user to perform a complicated re-teaching work for the downward correction of the command speed or the route change.

[0009]

According to the present invention, in a robot controller, a movement amount of each axis describing an interpolation point generated by an interpolation control according to a path plan is cyclically executed as an input. The above technical problem is solved by introducing a new idea into the processing related to the speed limitation of the shaft. That is, according to the present invention, in the processing related to speed limitation, the movement amount of each axis output to the servo control system in each processing cycle (1) does not conflict with the speed limitation of each axis, (2) Observe all-axis coordinated conditions,
(3) The movement amount that has been rotated to the non-output portion due to the speed limitation is determined according to the basic policy that the movement amount is preferentially output in the subsequent processing cycles.

More specifically, the following process is performed in the process of determining the output movement amount for each processing cycle. (1) If the remaining amount component of the movement amount of each axis that has not been output to the servo control system up to the previous processing cycle does not exist for this processing cycle, a new one is added in this processing cycle. All or part of the input movement amount should be included in the output to the servo control system as much as possible within the range that does not conflict with the speed limit of each axis, and the components that are not output in this processing cycle should be included in the next cycle. (2) If there is a remaining amount component of the movement amount of each axis that has not been output to the servo control system up to the previous processing cycle for this processing cycle, All or part of the remaining amount component should be included in the output to the servo control system in the current processing cycle to the maximum extent within the range that does not conflict with the speed limit of each axis, and (2-1) Current processing cycle Output to the servo control system If there is a residual component that does not exist, it is retained for the processing of the next cycle, and (2-2) there is no residual component that is not output to the servo control system in the current processing cycle, and When it is possible to further include at least a part of the movement amount newly input in the processing cycle in the output to the servo control system in the current processing cycle under the condition that it does not conflict with the speed limit of each axis. In addition to including all or part of the movement amount newly input in this processing cycle in the output to the servo control system in this processing cycle, the components not output in this processing cycle are It is retained for processing the cycle.

In order to consider the smooth transition to the deceleration control, the contents of the above process (2-2) are modified so that the following processing contents are obtained. (1) If the remaining amount component of the movement amount of each axis that has not been output to the servo control system up to the previous processing cycle does not exist for this processing cycle, a new one is added in this processing cycle. All or part of the input movement amount should be included in the output to the servo control system as much as possible within the range that does not conflict with the speed limit of each axis, and the components that are not output in this processing cycle should be included in the next cycle. (2) If there is a remaining amount component of the movement amount of each axis that has not been output to the servo control system up to the previous processing cycle for this processing cycle, All or part of the remaining amount component should be included in the output to the servo control system in the current processing cycle to the maximum extent within the range that does not conflict with the speed limit of each axis, and (2-1) Current processing cycle Output to the servo control system If there is a residual component that does not exist, it is retained for the processing of the next cycle, and (2-2) there is no residual component that is not output to the servo control system in the current processing cycle, and It is impossible to further include all the movement amount newly input in the processing cycle in the output to the servo control system in the current processing cycle under the condition that the speed limit of each axis is not in conflict with this. If it is possible if a part of the movement amount newly input in the processing cycle is possible, the part of the movement amount newly input in the current processing cycle is set to the servo in the current processing cycle. In addition to being included in the output to the control system, the components that are not output in the current processing cycle are retained for the processing in the next cycle, and (2-3) are not output to the servo control system in the current processing cycle. There is no residual component, and it is newly added in this processing cycle. If it is possible to further include all of the applied movement amount in the output to the servo control system in the current processing cycle under the condition that the speed limit of each axis is not violated, in the previous processing cycle, According to the ratio of the input movement amount of each axis to the servo control system in the previous processing cycle, all or part of the movement amount newly input in the current processing cycle is processed in this time. It is included in the output to the servo control system in the cycle, and if there is a component that is not output to the servo control system in the current processing cycle, it is held for the processing in the next cycle.

[0012]

According to the present invention, the robot controller is related to the speed limitation of each axis which is periodically executed with the movement amount of each axis describing the interpolation point generated by the interpolation control according to the route plan as an input. A new way of thinking is introduced into the processing. That is, according to the present invention, in the processing related to the speed limitation, the movement amount of each axis output to the servo control system in each processing cycle is (1) without violating the speed limitation of each axis. , (2)
It is decided to preferentially output (3) the movement amount that has been sent to the unoutputted portion due to speed limitation while maintaining the all-axis cooperation condition.

According to the present invention, when a movement command that conflicts with the speed limit for any axis is created during interpolation control, movement by all-axis cooperation can be performed at the maximum speed in the range that does not conflict with the speed limit. The components that have been performed and left without being completely moved are preferentially digested at the next and subsequent interpolations. Therefore, the range in which the locus of the robot deviates from the taught route is limited to the vicinity of the route section that violates the speed limit, and the deviation is quickly recovered.

Further, in the case where a movement command that does not conflict with the speed limit is continuously created for any of the axes during the interpolation control (when a movement command that conflicts with the speed limit is created during the interpolation control, Is the acceleration limit that the movement command satisfies,
Movement is performed at an acceleration and jerk that are equivalent to jerk limitation, and high trajectory accuracy is maintained.

In order to prevent the smoothness of deceleration from being broken during deceleration, it is preferable to take measures so that the movement amount output to the servo control system does not suddenly change in adjacent processing cycles. Therefore, if the unoutput portion has been carried over from the previous processing cycle, and if the carried over portion and the input portion of this time are output collectively, the speed limit will not be violated. A part of it may be carried over to the next processing.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing an outline of a general system configuration used for controlling a robot. As shown in the figure, the operation program is first read and interpreted (decoded) by the main CPU of the robot controller. As a result, the teaching path, the command speed, and the degree of positioning at each teaching point are designated. If there is an input that specifies the override to be less than 100%, the command speed is set to the value specified by the program itself multiplied by the specified override value.

In the subsequent path planning, a specific path planning including determination of the time constant of acceleration / deceleration control is made based on the designated items (teaching path, command speed, positioning degree at each teaching point, etc.). . Then, an interpolation point is generated for each axis based on this path plan (generation of interpolation point), and a condition regarding the speed limit of each axis (normally determined by the limit of the rotation speed of the motor. The same applies below) is checked. It If it violates the speed limit condition, some corrective measures are taken and the result is passed to the servo of each axis (speed limit of each axis).

As for the charge of the hardware, from the interpretation of the program to the generation of the interpolation points, the main CPU of the robot controller (sub CPU for each axis in some cases)
In general, the servo CPU of each axis receives the interpolation point via the shared RAM and executes the servo control of the motor of each axis.

The present invention achieves the intended object by devising software processing performed in the block of "speed limitation of each axis" in the above blocks. The contents of this software processing will be described below. The cyclic input to the "Speed limit of each axis" block and the corresponding output have the following contents. ● Input; Travel distance of each axis during interpolation control ● Output: Travel distance of each axis that satisfies the speed limit of each axis. That is, the amount of movement of each axis during interpolation control is modified as necessary to satisfy the speed limit of each axis.

In order to obtain the above-mentioned output in a form conforming to the idea of the present invention, consider the processing according to the following rules. Here, the input is received periodically, and each input includes the movement amount (1 set) for each axis. And
As described in the rules below, the following symbols are introduced because components that are not output in the process executed for each input and are output to the output in the process after the next input occur. .

[Symbol] k: An index representing the axis number of the robot, k = 1, 2 ...
N (N is the number of axes of the robot).

Mk: The amount of movement of the kth axis newly received this time. nk: The amount of movement of the kth axis received last time.

Rk: Amount of movement of the k-th axis carried over in this processing. That is, of the movement amount of the k-th axis received up to the previous time, the movement amount that has not been output by the previous process. Regarding the first input, rk = 0 for all axes. Mk: The maximum value of the movement amount of the k-th axis that is allowed within the range that does not conflict with the speed limit α: Proportion of components that can be output in this processing in the remaining amount rk. Here, since the processing of each time is performed so that the condition of cooperation of all axes is observed, α is set to a value common to all axes (0 ≦ α ≦ 1). That is, as will be described later, α is set differently with respect to the axis having the least margin with respect to the speed limiting condition. β: Proportion of the components that can be output in this processing, out of the movement amount mk newly received this time. For the same reason as in the case of α, β is also a value common to all axes (0 ≦ β ≦
1).

Γ: Ratio of the component output last time, out of the movement amount nk of the k-th axis received last time.

[Outline of Rules] 1. There is no carry-over movement amount that has not been output, that is, rk for all axes
= 0; Rule 1-1 = With respect to the moving amount mk of the current input, if there is no axis that is in conflict with the speed limit, mk is output as it is (β = 1). Rule 1-2 = If there is an axis that is in conflict with the speed limit, the movement amount βmk of the component that can protect the speed limit by cooperating with all axes
Is output and the remaining components are stored.

2. When the components that have not been output in the previous processing remain, that is, rk ≠ 0 for each axis
In this case, in this case, the unoutputted amount rk of each axis carried over from the previous time is preferentially output according to the following rule. Rule 2-1 = If rk> Mk in any axis, a part αr of rk in the maximum range where all axes can cooperate
Let k be the output of each axis. In this processing, the remaining amount component that has not been output and the entire movement amount mk received this time are stored as the carryover amount. Rule 2-2 = If rk <Mk for all axes, then include rk for each axis in 100% output. And r
The following processing is performed according to the magnitude relation between k + mk and Mk.

(1) When rk + mk> Mk on any of the axes, that is, if all the sum rk + mk of the carried amount of the remaining amount and the moving amount of the present reception are output by all-axis cooperation, the speed is output. When the restriction is violated, a combination of all rk and a part of mk βmk (0 <β <1) is output in all-axis cooperation.

(2) When rk + mk ≤ Mk for all axes, that is, it is possible to output all of the sum rk + mk of the amount of remaining carry-over and the amount of movement of this time received in cooperation with all axes. In some cases, the total amount r carried over from the previous time
The output of this time is a combination of k and a part of the movement amount γmk received this time. Here, as described above, γ represents the ratio of the previously output amount n k of the movement amount nk of the k-th axis that was previously output.

Here, although it is possible to output all of rk + mk in cooperation with all axes, what is not done is between the movement amount output in this processing and the movement amount output next time. This is for avoiding an excessive difference in.

A part of the movement amount nk received last time is the remaining amount r.
It is likely that a situation where the robot is output at a constant speed (teaching speed) is included in k (that is, γ <1), and from the viewpoint of speed limitation, all of rk + mk can be output by all-axis cooperation. )
Immediately after the transition from movement to deceleration. Therefore, this measure is meaningful in that the transition from the constant speed (teaching speed) movement to the deceleration state is smoothly performed.

The above is the "speed limitation of each axis" (see FIG. 1).
It is an outline of the rule regarding the processing in. Next, a processing procedure according to the above rule will be described with reference to the flowchart of FIG. 2 (speed limit related processing). Input of parameters including the maximum movement amount Mk corresponding to the maximum speed of each axis, setting of 2N buffer memories for storing the remaining amount value rk of each axis and the movement amount received for each ITP, etc.
Required preparations have been completed. First, rk and m
Initialize the 2N buffer memories that store k, rk
= Mk = 0 (step S1). Subsequent step S2
When the moving amount mk of the moving amount for this time is received, the magnitude relationship between the unoutput remaining amount rk and the maximum moving amount Mk of each axis is checked (step S3).

If in step S3 any k
If rk> Mk is satisfied (inconsistent with the speed limit), the processing of steps S4 to S6 is executed. Such a case occurs when the movement amount received last time (possibly before that) for any axis exceeds twice the maximum movement amount. First, αk that satisfies αk rk = Mk is calculated for each axis, and αk
Is calculated (step S4), and then αrk is output (step S5). Then, after updating the buffer value representing the remaining amount value to (1-α) rk + mk (step S6), the process returns to step S2 to receive the movement amount for the next time.

If rk ≤ Mk is satisfied (within the speed limit range) for all k in step S3, the process proceeds to step S7. This case is usually the case if the previously received displacement for any axis is between 1 and 2 times the maximum displacement.

In step S7, the magnitude relation between the maximum amount of movement Mk and the sum of the remaining amount rk and the current received amount of movement mk is checked. If either axis rk + mk
When> Mk, steps S8 to S10
Execute the processing of First, for each axis βk mk = Mk
Βk that satisfies the above is calculated, the minimum value β of βk is obtained (step S8), and then rk + βmk is output (step S9). Then, the buffer value representing the remaining amount value is set to (1-
After updating to β) mk (step S10), the process returns to step S2 to receive the movement amount for the next time.

On the other hand, if rk + mk ≤Mk is satisfied for all k in step S7 (within the speed limit range), the process proceeds to step S11. Such a case usually occurs after shifting from constant speed (teaching speed) movement to deceleration control. In particular, when the robot approaches the end point or another point where a high positioning ratio is taught, deceleration control is performed so that the speed approaches zero, so the amount of movement received each time gradually decreases to approach zero. In particular, just before the end point, there will be no next receipt. Therefore, the following processing is performed in steps S11 to S11.
The process of step S14 is executed. First, step S1
At 1, it is checked whether the current amount of movement mk received is the final one just before the end point. If so (Yes in step S11), r is output as the final output.
k + mk is output (step S12), and the process ends. Since deceleration control has been performed up to this stage, it is almost impossible that rk ≠ 0.
k will be output.

If NO in step S11, rk + γmk is output in the following step S12. As described in the section of definition of symbol, the coefficient γ related to mk represents the ratio of the previously output component in the previously received movement amount of the k-th axis. Therefore, after sufficient deceleration, γ =
Since it is 1 and rk is also 0, mk is actually output.

On the other hand, immediately after shifting from the constant speed (teach speed) movement to the deceleration control, the previously received movement amount nk
It is likely that there will be a situation in which a part of the above is included in the remaining amount rk, and from the viewpoint of speed limitation, all of rk + mk can be output by all-axis cooperation. If all of rk + mk is output even at such a stage, the next output that receives a smaller movement amount will decrease sharply compared to the current output.

In the processing of step 12, such a situation can be avoided by reflecting the previous output situation in the coefficient γ and determining the output of mk. In a succeeding step S13, the buffer value representing the remaining amount value is set to (1-γ) mk
Then, the process returns to step S2 to receive the movement amount for the next time.

By repeating the above-mentioned processing from the start to the end of the program reproduction operation of the robot, the robot movement can be realized while keeping the speed limit and minimizing the deterioration of the route without prolonging the cycle time. It

Finally, the path of the robot in the axial space realized for some cases will be briefly described with reference to FIGS. For convenience of explanation, the robot is set to the i-th
The chart is represented by the axis and the j-th axis, the horizontal axis represents the i-th axis position and the vertical axis represents the j-th axis position, and a chart representing a path corresponding to several times of processing is used. It is assumed that the maximum amount of movement common to the i-th axis and the j-th axis is equal, and that this is Mi = Mj = M. Further, in each figure, P0, P1, P2, ... Represent interpolation point positions (positions in the i-j axis space) created during interpolation control, and Q1, Q2 ,. It represents an interpolation point position (position passed to the servo) that is newly generated due to the restriction-related processing.

[Case 1 (FIG. 3)] In the route chart shown in FIG. 3, sections P0 P1, P1 P2, P2 P3 ...
In both cases, the increments of θi and θj do not exceed the limit value M. This represents a case where the movement amount that conflicts with the speed limit was not input in any processing cycle. In this case, the interpolation position created during interpolation control is passed to the servo as it is, and P0 → P1 → P2 → P
3 ... The moving route is realized.

[Case 2 (FIG. 4)] In the route chart shown in FIG. 4, θi and θj in sections P0 P1 and P2 P3 are shown.
The increment of does not exceed the limit value M, but in the interval P1 P2 θ
The increment of i exceeds the limit value M by δi. However, δi <
It is M. That is, if the movement amount of the section P1 P2 is passed to the servo as it is, it violates the speed limitation on the i-axis. In this case, M is output as the amount of movement of the i-axis in the processing cycle in which the amount of movement of the sections P1 and P2 is received.

Then, with α = M / (M + δi), j
As the movement amount of the axis, (input movement amount di x α) is output. As a result, the next movement target point of P1 is not P2 but Q
2, and δi and δj are sent to the subsequent processing as unoutput components.

In the next process, δi and δj are preferentially selected as the output components, but even if all δi and δj are output, it does not conflict with the speed limit. Therefore, the output of the movement amount in the section P2 P3 is further considered. . Here, the movement amount of section P2 P3 is 100
If you try to output%, it will violate the speed limit on the i-axis, so
The moving amount multiplied by the maximum ratio β (0 <β <1) allowed by the speed limit is sent to the output. This ratio is applied to both i-axis and j-axis (generally all axes). As a result, the next movement target point of Q1 is neither P2 nor P3, and the line segment P2 P3
The point becomes the upper point Q3, and εi and εj are sent to the subsequent processes as unoutput components.

Similarly, in the processing of the next cycle, ε
i and ε j are given priority as output components, and all of them are sent to the output. And this time, the movement amount of section P3 P4 is 100
% Output does not conflict with the speed limit (only ξ has a margin; ξ> 0). In this case, the movement amount of section P3 P4 is 10
If the output is turned to 0%, the next movement target point of Q3 will be P4. However, if the maximum movement amount is output in order to eliminate the unoutputted amount at once, the next movement amount may decrease sharply.

Therefore, it is preferable to use the previous output ratio β and set the point Q4 on P3 P4 at which the amount of movement of the i-axis becomes ε i + β × (the amount of i-axis movement between P3 and P4) as the movement target point. . Note that (1 + β) / 2 can be used instead of β in order to speed up the elimination of the unoutputted portion. If section P3 P
If a small movement amount is continuously input after 4
Eventually, the non-output portion is eliminated, and the route returns to the route according to the movement command created during the interpolation control.

[Case 3 (FIG. 5)] In the route chart shown in FIG. 5, in sections P0 P1, P2 P3, θi, θj.
The increment of does not exceed the limit value M, but in the interval P1 P2 θ
The increment of i is twice the limit value M and exceeds 2M by φi. However, φi <M. This violates the speed limit in the processing cycle when the movement amount of the section P1 P2 is received, and
This shows a case where the digestion cannot be completed in one processing cycle.

In this case, M is output as the amount of movement of the i-axis in the processing cycle in which the amount of movement of the sections P1 and P2 is received. Further, as α = M / (2M + φi), (moved amount of input × α) is output as the moved amount of the j-axis. As a result, the next movement target point of P1 becomes Q2. Then, the movement amount of each axis between the sections Q2 and P2 is sent to the subsequent processing as a non-output component.

In the next processing, the non-output portion carried over from the previous time is preferentially set as the output component, but if all of it is output, it violates the speed limit for the i-axis, so the output of the i-axis is the same as the previous time. Let M. In this way, the next movement target point is Q
It becomes 3. And the non-output component carried over next time is
For the i-axis, φi + Δi and φj + Δj. Note that φ
j is a movement amount component of the j axis corresponding to φi, and is not shown.

In the processing of the next cycle, a section P3 is newly added.
The movement amount of P4 (P4 is not shown) is input, but φ
i + Δi and φj + Δj are preferentially included in the output component.
The movement amount of the section P3 P4 is the same as that described in Case 2, and a part or all of it is further added to the output.

As can be understood from the three cases described above, when the control method of the present invention is applied, the conditions of all-axis cooperation are adhered to for the output in each processing cycle, and the unoutputted portion is left due to the speed limitation. Even if occurs, it will be preferentially digested after the next time, and it will return to the original route. Therefore, it is possible to prevent the unoutputted moving amount from being piled up and causing a large decrease in trajectory accuracy. It is also possible to take a measure (for example, refer to the description of Case 2) so that a movement command that impedes the smoothness of deceleration is not passed to the servo because the return to the original route is too quick. .

[0052]

According to the present invention, it is possible to perform control such that a corrected movement path is taken only for a portion that violates the speed limit of each axis, and that the teaching path is quickly returned after passing through the portion. . Therefore, high override (eg; 1
(00%) Even when a program in which a conflict with the speed limit condition occurs on any axis during program execution, the locus where the conflict occurs is almost the same as when taught with a low override. . As a result, the user is not required to perform the downward correction work of the command speed or the complicated re-teaching work for changing the route.

[Brief description of drawings]

FIG. 1 is a block diagram showing an outline of a general system configuration used for controlling a robot.

FIG. 2 is a flow chart outlining speed limit related processing executed in an embodiment of the present invention.

FIG. 3 is a path chart for explaining the relationship between the path of the robot in the axis space created during interpolation control and the path of the robot in the axis space passed to the servo for Case 1.

FIG. 4 is a path chart for explaining the relationship between the path of the robot in the axis space created during interpolation control and the path of the robot in the axis space passed to the servo for Case 2.

FIG. 5 is a path chart for explaining the relationship between the path of the robot in the axis space created during interpolation control and the path of the robot in the axis space passed to the servo for Case 3;

[Explanation of symbols]

P0, P1, P2 ... Interpolation point position created during interpolation control Q1, Q2, Q3 ... In each case 1 to 3, interpolation point position newly generated by speed limit related processing M Speed of each axis Maximum movement corresponding to the limit

Claims (2)

[Claims] 1. A software controller in a robot controller creates a route plan based on a program describing an operation including a route movement, generates interpolation points by interpolation control according to the route plan, and executes the interpolation control at the time of the interpolation control. Using the movement amount of each axis that describes the generated interpolation point as a periodic input, the processing related to the speed limit of each axis is executed periodically, and the movement of each axis is performed so that the speed limit of each axis is observed. In a robot control method in which an amount is periodically output to a servo control system of each axis, a process related to speed limitation of each axis is a movement amount output to the servo control system, a speed of each axis. The process includes a process of determining each processing cycle so as not to violate the restriction and keep the all-axis cooperative condition. (1) If the servo control is performed by the previous processing cycle, To the system If the remaining component of the movement amount of each axis that has not been applied is not present for this processing cycle, all or part of the movement amount newly input in this processing cycle is limited to the speed of each axis. (2) Until the previous processing cycle, hold the components that are not output in the current processing cycle for processing in the next cycle, and include them in the output to the servo control system to the maximum extent within the range where If there is a remaining amount component of the movement amount of each axis that was not output to the servo control system in this processing cycle, all or part of the remaining amount component conflicts with the speed limit of each axis. Within the range not included, the output to the servo control system in this processing cycle is included as much as possible, and (2-
1) If there is a remaining amount component that is not output to the servo control system in the current processing cycle, this is retained for processing in the next cycle, and (2-2) is not output to the servo control system in the current processing cycle. Under the condition that there is no remaining amount component and at least part of the movement amount newly input in this processing cycle does not conflict with the speed limit of each axis, the servo control system in this processing cycle If it is possible to further include in the output, all or part of the movement amount newly input in this processing cycle should be further included in the output to the servo control system in this processing cycle. The robot control method, wherein a component that is not output in the current processing cycle is retained for processing in the next cycle. 2. A software controller in a robot controller makes a route plan based on a program describing an operation including a route movement, generates interpolation points by interpolation control according to the route plan, and executes the interpolation control at the time of the interpolation control. Using the movement amount of each axis that describes the generated interpolation point as a periodic input, the processing related to the speed limit of each axis is executed periodically, and the movement of each axis is performed so that the speed limit of each axis is observed. In a robot control method in which an amount is periodically output to a servo control system of each axis, a process related to speed limitation of each axis is a movement amount output to the servo control system, a speed of each axis. The process includes a process of determining each processing cycle so as not to violate the restriction and keep the all-axis cooperative condition. (1) If the servo control is performed by the previous processing cycle, To the system If the remaining amount component of the movement amount of each axis that has not been applied is not present for this processing cycle, all or part of the movement amount newly input in this processing cycle is limited to the speed of each axis. (2) Until the previous processing cycle, hold the components that are not output in the current processing cycle for processing in the next cycle, and include them in the output to the servo control system to the maximum extent within the range where If there is a remaining amount component of the movement amount of each axis that was not output to the servo control system for this processing cycle, all or part of the remaining amount component conflicts with the speed limit of each axis. Within the range not to be included, the output to the servo control system in the current processing cycle is maximally included, and (2-1) if there is a residual component that is not output to the servo control system in the current processing cycle, For processing the next cycle (2-2) There is no residual amount component that is not output to the servo control system in the current processing cycle, and the entire movement amount newly input in the current processing cycle is the speed of each axis. It is impossible to further include in the output to the servo control system in this processing cycle under the condition that the restriction is not violated, but if it is a part of the movement amount newly input in this processing cycle, it is If possible, the part of the movement amount newly input in the current processing cycle is further included in the output to the servo control system in the current processing cycle, and is not output in the current processing cycle. The component is retained for the processing of the next cycle, and (2-3), there is no residual component which is not output to the servo control system in the current processing cycle, and is newly input in the current processing cycle. The entire amount of traveled is violated by the speed limit of each axis. If the stomach condition it is possible further to include in the output to the servo control system in the current processing cycle, of the amount of movement of each axis is entered in the last processing cycle,
Depending on the ratio output to the servo control system in the previous processing cycle, all or part of the movement amount newly input in the current processing cycle is included in the output to the servo control system in the current processing cycle. The robot control method described above, wherein if there is a component that is not output to the servo control system in the current processing cycle, that component is held for processing in the next cycle.