JPS60207780A - Master/slave manipulator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field to which the Invention Pertains] The present invention is based on the signals of a position detector and a torque detector which are assigned r*a for each degree of freedom of a multi-degree of freedom master arm and slave arm.゛Regarding a master-slave manipulator configured with a C feedback type bilateral servo system, related to a master-slave manipulator that removes the self-weight component from the torque detector signal in order to improve the operability of the master arm. Problems] Pilateral servo systems are known as symmetrical, force reversal, and force feedback types, but the basic concept is to allow the person operating the mask to feel the external force applied to the slave. ,
Since the purpose is to improve operability, it is necessary to somehow prevent the dead weight components of the mask and slave from entering the feed pack loose.

Conventionally, most master-slave manipulators use counterweights or springs in each degree of freedom to mechanically balance the weight components of the master arm and slave arm. However, this method is structurally difficult to apply to an articulated master-slave manipulator with many degrees of freedom.

Therefore, the current posture of the manipulator is determined based on the signal from the position or angle detector attached to the manipulator's joints, actuator section, or deceleration section, and from there, a computer is used to calculate Some actuators are configured to calculate the arm's own weight component and compensate for it in the actuator itself. FIG. 1 is a block diagram of the master-slave manipulator of this force feedback type bilateral servo system when it is in use, with the mask side as A and the slave side as B and C and C. 1 and 14 are the motor parts on the mask side and the slave side, respectively, 2.15 are the speed detectors, and 3.1
6 is a torque or force detector, and 4.17 is a position or rotation angle detector, respectively. 5.11 is a motor driver, 6.12 is an amplifier, 7 and 13 are gravity component calculation units, 8.10 is a control compensator, and 9 is a mask dead weight output voltage calculation unit. When using one computer in Fig. 1, AD conversion, DA
conversion has been done.

In the operation shown in FIG. 1, first, in the slave side loop, there is a loop in which the signal from the mask side position detector 4 is set as a target value and the signal from the C1 slave side position detector 16 follows this, and the control compensator 10 The slave motor 14 is driven by the C1 driver 11 using the processed signal and a signal obtained by negative feedback of the signal from the slave speed detector 15 in order to improve damping characteristics. The mask-side loop calculates the mask value by the gravity component calculating section 7 from the signal of the mask-side torque detector 3, the signal of the mask-side position detector 4, and the signal 18 of the position detector of other mask joints. Using the self-weight component torque signal, the force component signal excluding the self-weight component on the first mask side, the signal of the slave-side torque detector 16, the signal of the slave-side position detector 17, and the position of other slave joints are detected. gravity component calculation unit 13 from the signal 19 of the
A loop in which the mask side force component signal follows the slave side force component signal in the force component signal excluding the slave side self weight component using the slave self weight component torque signal calculated by C1. The signal processed by the control compensator 8 and the signal from the master dead weight output voltage calculation unit 9 that calculates a voltage value sufficient to convert the mask side dead weight component torque into motor torque, and the signal processed by the control compensator 8 in order to improve damping characteristics. The master side motor 1 is driven by the driver 5 using a signal obtained by negative feedback of the signal from the speed detector 2 on the mask side.

In this way, the C operator uses the gravity component as a force sensation, feels only the external force component without feeling °C, and is also able to stand still in any position when no external force acts, similar to gravity compensation using a counterweight or spring.

However, in this method, the gravity component calculation, which requires a huge amount of calculation, is placed on the mask side and the slave side, and when the degree of freedom increases, the calculation time increases, and the sampling time also increases. The length increases, leading to deterioration in operability. Furthermore, in order to shorten the sampling time in order to improve operability, a large, high-speed computer is required, making the system expensive.

In order to compensate for these drawbacks, the arm posture calculation in the self-weight component calculation of the master-slave manipulator was performed on either the mask or the slave, thereby reducing the amount of calculation compared to the conventional method. This is the one described in JP-A-58-71085, as shown by 'C'.

This is based on the assumption that the mask and slave always have substantially the same posture, and the c1 arm posture is calculated only for one of them.

However, according to this method, the attitude error of the master and slave due to delay time etc. is not taken into account. As a result, accurate gravity compensation is not performed, resulting in poor operability and fatigue for the operator.

[Purpose of the invention]

The present invention improves the entry point of the conventional method described above,
The purpose of the present invention is to provide a master-slave manipulator that reduces calculation time on a computer and has good operability.

[Summary of the invention]

The present invention provides a master-slave manipulator that configures a force feedback type bilateral servo system for each degree of freedom of the master arm and slave arm, which have multiple degrees of freedom. From the signal from the position sensor, an intermediate posture between the mask posture and the slave posture is determined, and based on the intermediate posture, the torque due to the arm's own weight applied to the actuator that drives each degree of freedom of the mask and slave is calculated, and the torque of the arm's own weight is calculated based on the intermediate posture. The result obtained by subtracting the self-weight torque from the torque signal of the torque detector installed in each degree of freedom is divided into 1 as the external force torque.
This master-slave manipulator is characterized in that it is used together with a mask-side force sensing signal of a force feedback type master-slave manipulator.

〔Effect of the invention〕

With the present invention, arm posture calculations that conventionally required a huge amount of calculation can be reduced by almost half, and the master-slave system has good operability without being significantly affected by tracking errors on the mask and slave sides. A manipulator becomes possible. .

[Embodiments of the invention]

FIG. 3 is a block diagram showing an embodiment of the present invention. The mask position follow-up loop for 0 slave drive is the same as in the conventional example, so its explanation is omitted. A seven-stacker feedback loop for the master drive connects the mask side force detector 38. Slave side force detector 48. Mask side position detector 39. Slave side position detector 49. Arm dead weight component calculation unit 50. Master dead weight component output voltage calculation unit 51. Position signals 52 for each of the mask and slave on the other degrees of freedom axes. Control compensator 42. Mask side speed detector 37. Amplifier 41. Driver 40. It consists of a motor 36. This loop connects the signal of the mask-side torque detector 38 and the position detector 39 of each mask-side slave side.
．． 49 and the signal 52 of the position detector of each other degree of freedom axis of the master slave, the intermediate posture of the master and the slave is determined, and based on this, the dead weight component calculation unit 5o calculates the dead weight component of each of the mask and slave. Only the external force component acting on the mask axis is determined from the master self-weight component signal from the master self-weight component signal from
Only the external force component acting on the slave shaft is calculated from the slave self-weight component signal from 0. Furthermore, a calculation of so-called force feedback type bilateral control is performed from this external force torque component on the slave side on the mask side, and the output thereof is inputted to the driver through the control compensator 42. In addition, as a force to be substituted for the counterweight, the input voltage to the driver for maintaining the balance state of the C1 master arm is determined from the mask dead weight component signal C through the mask dead weight component output voltage calculating section 51, and it is input to the driver. do. Further, the signal from the mask-side speed detector 37 is amplified by an amplifier 41, and is input into a negative feedback loop to the driver in order to improve the damping characteristic.

In this way [C using the intermediate value of the master and slave position signals]
By performing the attitude calculation for calculating the gravity component, the calculation time is approximately half that of the case where the attitude calculation is performed separately for the master and slave, as shown in the conventional technique shown in Fig. 1. Therefore, the computer can be made smaller, It is possible to reduce the cost, and to use the conventional technology [as shown in Figure 2, instead of using only one position signal, the intermediate value of both position signals of the master and slave is taken, so it is possible to reduce the delay time, etc. It is possible to significantly reduce the influence of position errors and realize a compact, low-cost controller with good operability.

[Other embodiments of the invention]

In another embodiment of the present invention, in the case of a force feedback type bilateral master slave manipulator, the frictional force component on the slave side is also felt as a load on the mask side. As a result, operability is greatly degraded.

Therefore, a constant voltage for frictional force compensation is added to the gravity compensation voltage in a direction that matches the sign of the torque signal on the slave side.
Gravity compensation and frictional force compensation can be performed simultaneously.

[Brief explanation of drawings]

Fig. 1 is a control block diagram for one axis of a force feedback type bilateral master-slave manipulator that includes a conventional self-weight compensator, and Fig. 2 shows a conventional self-weight compensator that substitutes position signals for both arms using mask position signals. FIG. 3 is a control block diagram regarding one axis of the force feedback type pilateral master-slave manipulator. FIG. 3 is a control block diagram regarding one axis of a force feedback type bilateral master slave manipinulator showing an embodiment of the present invention. 1, 20.36... Master side drive motor 14, 31.
46...Slave side, drive t-ri 2, 21.37 ・
...Mask side speed detector 15, 32.47...Slave side 7 detection spring 3, 22.38...Mask side torque detector 16, 33.48...Slave side 1 rotation Bundon 4, 23.39 ...Mask side position detector 17, 3
4.49...Slave side <x t IL beast red 5, 24
．． 40...Mask side motor driver 11, 29.4
4...Slave side-tP91-to lie'6, 12.
25.30.41.45...Amplifier 8, 27.42.
・・Mask side control compensator 10, 28.43 ・・Slave side control &-7 葎 薯器 7 ・・Mask self-weight component calculation unit 13 ・・Cold trench compensation to slave side 1 18.35 ・・・Mask side other degrees of freedom axis position detector signal 9.51 ・・Master dead weight component output ′ Tortoise pressure calculation unit 26
．． 50... Master, slave self-weight component calculation unit 52,
...Musk, Slag, and other degrees of freedom axis position detector signal agent Patent attorney Noriyuki Chika (and 1 other person) Figure 2

Claims (1)

[Claims] In a master-slave manipulator configured with a C1 force feedback type bilateral servo system for each degree of freedom of the master arm and slave arm, which have multiple degrees of freedom, the position control unit attached to each degree of freedom of the master arm and slave arm From the signal, determine the intermediate posture between the mask posture and the slave posture, and based on the intermediate posture, calculate the torque due to the arm's own weight that is applied to the actuator that drives each degree of freedom of the mask and slave, and apply the torque to each degree of freedom of the master slave. A master-slave manipulator, characterized in that the result obtained by subtracting the self-weight torque from the torque signal of a provided torque detector is used as an external force torque, and used as a signal for force feedback calculation.