JPH02204805A - Follow-up controller - Google Patents

Abstract

PURPOSE:To stop no control even if step-out is generated, and also, to contrive the recovery of step-out in a state that a control system is stable by providing a step-out detecting means, a target quantity sending-out control means, and a speed instructing means. CONSTITUTION:A step-out detecting means 7 receives an actual position from a control object and detects whether the control object is brought to step-out due to a follow-up delay against a position of a movement command or not. When step-out is detected by this step-out detecting means, a target quantity sending-out control means 2 discontinues a supply to the control object of a movement instruction from this time on, and also, a speed command is supplied to the control object from a speed command means 3. Subsequently, when it is detected by the step-out detecting means that step-out of the control object is recovered, the supply to the control object of the movement command is restarted from this time on. In such a way, even if step-out is generated, the control is not stopped, and also, in a state that the control system is stable, the recovery of step-out can be contrived.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to improvements in follow-up control devices.

(Prior Art) There is a technique applied to a manipulator, for example, as a follow-up control device. In this technique, a movement command for the manipulator hand is issued from a movement command generator, and the actual position of the manipulator hand at this time is detected. Then, the deviation between the movement command and the actual position is determined and supplied to the manipulator, and the manipulator moves in response to this deviation, and the hand reaches the target position.

However, for example, if the amount fr of the load gripped by the manipulator hand is large, the actual movement position F of the manipulator hand will be the position G specified by the movement command, as shown in FIG.
It gradually lags behind. If this delay becomes large, loss of synchronization will occur. When step-out occurs in this way, the response is to emergency stop the movement when the delay in the position of the manibrator hand relative to the movement command exceeds a predetermined amount.

However, depending on the operation of the manipulator and other objects to be controlled, there may be cases where it is desired to continue the control without stopping even if there is a delay in the actual position of the hand, and in such cases, the control may be stopped as described above. It will be completely difficult for technology to respond. Furthermore, if the operation is not stopped when step-out occurs, the amount of delay increases, causing the following problem. In other words, when follow-up control is performed digitally, overflow occurs in registers, etc., and when it is performed analogously, saturation occurs in the internal circuit, and in either case, the control system becomes unstable. Put it away.

(Problem to be solved by the invention) As described above, the technology for stopping control when step-out occurs cannot be applied to a controlled object that is not desired to be stopped, and if it is not stopped, the control system becomes unstable. .

SUMMARY OF THE INVENTION An object of the present invention is to provide a follow-up control device that does not stop control even if a step-out occurs and can recover from the step-out while keeping the control system in a stable state.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides the controlled object with the deviation between the position indicated by the movement command and the actual position fed back from the controlled object to cause the controlled object to follow the movement command. In the tracking control device that controls, there is a step-out detection means that receives the actual position of the controlled object and detects whether the controlled object is delayed in following the movement command and a step-out has occurred, and this step-out detection means detects the step-out. The supply of the movement command to the controlled object is interrupted from the time when the synchronization is detected, and the supply of the movement command to the controlled object is resumed from the time when the loss of synchronization of the controlled object is detected by the step-out detection means. This tracking control device is equipped with a target amount sending control means and a speed command means for supplying a speed command of 0 (zero) to a controlled object at least when the controlled object is out of synchronism.

(Function) By having such means, the step-out detection means receives the actual position from the controlled object and detects whether the controlled object has lost synchronization due to a delay in tracking the position of the movement command, When step-out is detected by the step-out detecting means, the target amount sending control means stops supplying the movement command to the controlled object from this time, and at the same time supplies a speed command from the speed command means to the controlled object.

Then, when the step-out detection means detects that the control object has recovered from step-out, supply of the movement command to the control object is resumed from this time.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is an overall configuration diagram of the follow-up control device. In the same figure, 1 is a controlled object such as a manipulator, while 2 is a movement command generation device that issues a movement command to the m controlled object 1;
Reference numeral 3 denotes a speed command generation device that issues a speed command to the controlled object 1. The movement command generated by the movement command generation device 2 is sent to the adder 4, and the speed command generation device 3
The speed command generated by is sent to an adder 5. Control m of the controlled object 1 (position and moving speed of the controlled object)
is sent to the speed position detector 6, which detects the current position from the controlled amount and sends it to the adder 4, and also detects the current speed from the controlled amount and sends it to the adder 5. are doing. A step-out detection device 7 is connected to the output end of the adder 4, and an adder 5 is connected to the output end of the step-out detection device 7 through a position control compensator 8. Then, the controlled object 1 is passed through the speed control compensator 9 to the output terminal of the adder 5.
is connected. The step-out detection device 7 receives the deviation output of the adder 4, that is, the deviation between the position instructed by the movement command and the current position of the controlled object 1 fed back from the speed position detector 6, and detects that this deviation is equal to or greater than a predetermined amount. It has a function of detecting that the controlled object 1 is out of synchronization when this occurs, and sending out an out of synchronization detection signal to the movement command generating device 2. Further, this step-out detection device 7 has a function of bringing the controlled object 1 to an emergency stop when the moving speed of the controlled object 1 becomes overspeed or comes to a stop. The movement command generating device 2
When receiving a step-out detection signal, it interrupts the transmission of the movement command, and when the power to send the step-out detection signal is lost, it resumes sending the movement command from the point where the movement command was interrupted. have. Further, the speed command generation device 3 transmits a speed command corresponding to the actual movement speed of the controlled object 1 from the time when the transmission of the movement command by the movement command generation device 2 is interrupted, and the movement command generation device It has a function of stopping sending out the speed command when the movement command is sent out again from 2.

Next, the operation of the apparatus constructed as described above will be explained with reference to the control flowchart shown in FIG. When the movement command J is sent from the movement command generation device 2, this movement command J is sent to the adder 4. On the other hand, the speed and position detector 6 receives the control amount of the controlled object 1, detects the current speed and position of the controlled object 1, and sends them to the adders 5 and 4, respectively. Thereby, the adder 4 calculates the deviation between the position specified by the movement command and the current position of the controlled object 1, and sends it to the step-out detection device 7.

In step sl, the step-out detection device 7 determines from the deviation output of the adder 4 whether the deviation between the position instructed by the movement command and the current position of the controlled object 1 is greater than or equal to a predetermined amount.

Then, as a result of this judgment, if the deviation amount is not greater than a predetermined amount, it is judged that step-out has not occurred, and step S2
Then, the deviation amount from the adder 4 is sent as is to the position control compensator 8. As a result, this deviation amount is subjected to position compensation by the position control compensator 8, then passes through the adder 5, is speed compensated by the speed control compensator 9, and is sent to the controlled object 1.

Therefore, the controlled object 1 moves according to the amount of deviation.

When the follow-up control is being performed in this way, the load on the controlled object 1 is large, and as shown in FIG. 3, the deviation mR between the position J specified by the movement command and the actual position of the controlled object 1 is
gradually increases to a predetermined amount or more at time t, the step-out detection device 7 detects the control target 1 in step sl.
Detects that a step-out has occurred. Then, in steps s3 and S4, the step-out detection device 7 determines whether the cause of the step-out is due to the overspeed of the controlled object 1 or to the stoppage of the controlled object 1, based on the detected speed from the position and speed detector 6. If it is determined from these judgments that the controlled object 1 is not overspeeding or stopped, the step-out detection device 7 moves to step s5 and sends a step-out detection signal to the movement command generation device 2.

Therefore, the movement command generating device 2 stops sending out movement commands from the moment it receives the step-out detection signal.

At the same time, the step-out detection device 7 holds and outputs the movement command when the movement command was interrupted. Additionally, the speed command generation device 3 receives the speed detected by the speed position detector 6 through the step-out detection device 7 and the movement command generation device 2, and determines the same speed as the movement speed of the controlled object 1 when the movement command is interrupted. Send a command. Thereby, this movement command is sent to the controlled object 1 through the adder 5 and the speed control compensator 9. As a result, the controlled object 1 continues to move at the moving speed when the movement command was interrupted, and as a result, the deviation between the position J specified by the movement command and the actual position of the controlled object 1 gradually becomes smaller. When this deviation becomes equal to or less than a predetermined amount, the step-out detection device 7 determines in steps S1 and s2 that the step-out state of the controlled object 1 has been recovered, and stops sending out the step-out detection signal. As a result, the movement command generation device 2 starts transmitting the movement command following the previously interrupted movement command.

Also, at this time, the speed command generation device 3 is the movement command generation device 2.
The transmission of the speed command is stopped from the time when the transmission of the movement command is started. Note that the predetermined amount of deviation when detecting and determining step-out in the step-out detection device 7 is different from the predetermined amount of deviation when detecting and determining recovery from step-out.

In this way, in the above embodiment, when a step-out of the controlled object is detected in response to the control amount from the controlled object 1, the supply of movement commands to the controlled object 1 is interrupted from this time, and When it is detected that the step-out has recovered, the supply of movement commands to the controlled object 1 is restarted, so even if the controlled object 1 loses synchronization, the controlled object 1 will not be stopped. Can recover from loss of synchronicity. In this case, since the controlled object 1 is moved at the moving speed at which the step-out was detected by the speed command,
The controlled object 1 can smoothly recover from the step-out state. As a result, even if the device is configured digitally, the registers and the like will not overflow, and even if the device is configured analogously, the internal circuit will not be saturated, so that the control system can be stabilized. However, if the above device is applied to a multi-axis manipulator, for example, even if a follow-up delay occurs in only one axis, the entire manipulator can continue to operate without stopping.

Note that the present invention is not limited to the above-mentioned embodiment, and may be modified without departing from the spirit thereof. For example, although the speed command generating device 3 is configured to send a speed command only when step-out occurs, it may be configured to send a speed command not only at this time but also at all times. Further, the step-out detection device 7 detects step-out based on the deviation between the position instructed by the movement command and the actual position of the controlled object 1. It may be detected by

[Effects of the Invention] As detailed above, according to the present invention, there is provided a follow-up control device that does not stop control even if a step-out occurs and can recover from the step-out while keeping the control system in a stable state. Can be provided.

[Brief explanation of the drawing]

1 to 3 are diagrams for explaining one embodiment of the follow-up control device according to the present invention, in which FIG. 1 is an overall configuration diagram, FIG. 2 is a control flow diagram, and FIG. 3 is a step-out diagram. FIG. 4 is a diagram for explaining the conventional technique. 1...Controlled object, 2...Movement command generator, 3...
- Speed command generation device, 4.5... Adder, 6... Speed position detector, 7... Step-out detection device. Applicant's agent Patent attorney Takehiko Suzue

Claims (1)

[Claims] In a tracking control device that controls the controlled object to follow the movement command by supplying the controlled object with a deviation between a position indicated by a movement command and an actual position fed back from the controlled object, the actual position of the controlled object is controlled. a step-out detection means for detecting whether or not the controlled object is delayed in following the movement command and a step-out has occurred; Target amount sending control means that interrupts the supply to the controlled object and restarts the supply of the movement command to the controlled object when the out-of-step detection means detects that the out-of-step has recovered from the controlled object; A follow-up control device comprising: speed command means for supplying a speed command to the controlled object at least when the controlled object is out of synchronization.