JPH07276266A - Master arm of multiaxis master/slave type servo manipulator - Google Patents

Abstract

PURPOSE:To operate the grip of a master arm smoothly and lightly at starting the master arm by compensating static friction torque due to a motor actuator of each axis provided on the master arm of a multiaxis master/slave type servo manipulator. CONSTITUTION:Respective axes 3 of a master arm 1 are respectively provided with speed detectors 8, the grip 2 of the master arm 1 is provided with a switch actuating by gripping, and by operating the switch, static friction compensating torque is supplied to each axis of the master arm 1 so as to be able to improve operability of the master arm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a master arm of a multi-axis master / slave type servo manipulator.

[0002]

2. Description of the Related Art A torque detector is provided on an output shaft of a motor actuator provided on each shaft of a master arm, and the torque applied to the output shaft when a person operates the master arm is detected and detected. The torque is supplied by each motor actuator so as to cancel the torque to zero and improve the operability of the master arm.

[0003]

The torque detector is susceptible to noise, and in order to prevent noise from mixing in, a torque detector is provided with a widening device, which makes the torque detector large and difficult to assemble into the master arm. Becomes Further, when a gear chain is used, it is easily affected by the torque of the other shaft, and the torque applied to the output shaft of the actuator motor cannot be accurately detected. As a result, the output torque of the actuator motor becomes excessive and deficient, and the operator feels that the master arm becomes heavy or light, and smooth operation cannot be performed.

[0004]

Means for solving the above-mentioned problems in the present invention is, in a master arm of a multi-axis master / slave type servo manipulator, a motor actuator and speed detection for each axis of the master arm. And a switch that operates when the grip of the master arm is gripped is provided, and the output voltage when the master arm starts moving is set in advance in the speed setting device of the speed detector, and this is used as the start confirmation speed. In addition to setting, the static torque when the master arm starts to move is set as the static friction compensation torque in the torque setting device of the motor actuator, and the master arm is stationary when the grip switch is operated. The static friction compensation torque in the direction opposite to the previous operation direction (forward direction) In addition to supplying from the actuator to the master arm, the supply of this static friction compensation torque is stopped when the start confirmation speed is reached, making the operation in the opposite direction to the previous operation direction smooth and light. To be able to do.

The static friction compensation torque is supplied to the master arm when the grip switch is operated and the master arm is operated in the forward direction to stop, and then the switch is turned off and the switch is operated again. By supplying the static friction compensation torque in the same direction as, it is possible to smoothly and smoothly perform the operation in the same direction as the previous operation direction.

[0006]

When the operator grips the grip of the master arm to operate the master arm, the switch operates to supply the static friction compensation torque to each axis of the master arm. Therefore, the operator can move the master arm by applying a slight force to the grip. If the master arm moves, the movement of the master arm is detected by the speed detector, and the supply of the static friction compensation torque to the axis confirmed to move is cut off. When the master arm moves and changes from static friction to dynamic friction, the friction resistance torque is reduced to a fraction to a few tenths. Therefore, the master arm can be operated smoothly even without the supply of dynamic friction compensation torque. .

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The master arm of a multi-axis master / slave type servo manipulator is, for example, that shown in FIGS. 1 and 2 of Japanese Patent Publication No. 58-37116, and a large number of motor actuators and gear reducers are used. However, in order to facilitate understanding, a single-axis master arm will be described below.

FIG. 1 shows an example of a uniaxial master arm, and FIGS. 1 (A), (B) and (C) show the stopped state after the operation, for explaining the direction of the static friction compensation torque. FIG. In FIG. 1, 1 is a master arm, 2 is a grip provided on one end of the master arm 1, and 3 is a shaft on which the other end of the master arm 1 is fitted. Reference numeral 4 denotes a gear (1) fitted to the shaft 3 and fixed to the master arm 1. Reference numeral 5 is a motor actuator, 6 is an output shaft of the motor actuator 5, and 7 is a gear (2) fitted to the output shaft 6, which meshes with the gear (1) 4. A speed detector 8 is directly connected to the motor actuator 5.

2A and 2B are explanatory views of the grip 2 portion. FIGS. 2A, 2B and 2C show examples in which different switches are attached, and FIG. 2D is a reflection type photoelectric switch. It is a figure which shows the operating principle of. FIG. 2A shows the push button switch 10 in which only the button portion is projected and the other portion is embedded in the grip 2. When the operator grips the grip 2 with the hand 9, the protruding button portion is shown. Is pressed and pushbutton switch 1
In FIG. 2B, in which 0 operates, the light projector 12 is embedded in the grip 2, the U-shaped bridge 11 is provided in the grip 2, and the light receiver is provided at a position facing the light projector 12 on the grip 2 side of the bridge 11. It is embedded with 13,
When the grip 2 is gripped by the hand 9 and the light between the light projector 12 and the light receiver 13 is blocked, the phototransistor of the light receiver 13 performs a switching operation. FIG. 2C shows the grip 2 with a light emitter / receiver 14 embedded therein.
2D, the reflected light is projected and received as shown in FIG.
Is detected and the built-in phototransistor performs a switching operation.

In the uniaxial master arm constructed as described above, first, the output torque of the motor actuator 5 is gradually increased to measure the torque T when the master arm 1 starts to move. It is set as a static friction compensation torque in the torque setting device provided in. Next, the output voltage α of the speed detector 8 for confirming that the master arm 1 has begun to move is determined, and is set by the speed setter as the starting confirmation speed like the torque T. When the operator grips the grip 2 to operate the master arm 1, a switch provided on the grip 2 operates, and the master arm 1 is stationary, and the master arm 1 is stationary in a direction opposite to the previous operating direction. When the motor actuator 5 supplies the friction compensation torque T to the master arm 1 through the output shaft 6 and the master arm 1 starts to move by the operation of the operator's hand and the output voltage of the speed detector 5 reaches a predetermined set value α. The supply of the static friction compensation torque T is stopped. Therefore, the operation in the direction opposite to the previous operation direction can be performed extremely smoothly and lightly.

When the master arm is stopped after finishing the operation, the motor actuator 5 passes the output shaft 6 through the output shaft 6 and applies the static friction compensation torque T in the opposite direction to the operation direction up to now when the grip 2 is left to be gripped. Since it is supplied to 1, the operation can be performed extremely smoothly and lightly when the operation direction is alternately operated in the forward direction and the reverse direction, but static friction occurs when the operation is performed in the forward direction and then in the forward direction again. Since the compensation torque T is supplied in the opposite direction, the master arm 1 cannot be moved or becomes very heavy. In this case, the grip 2 is gripped again to reset the static friction compensation torque.

FIGS. 3 and 4 are diagrams for explaining these operations. In both figures, the horizontal axis is the time axis showing the elapsed time, and (A) is the operating state of the switch provided on the grip 2 described in detail above. That is O
The state of N, OFF is shown, the state of supplying the static friction compensation torque T is shown as (+) in the forward direction as (-) in the reverse direction, and the output voltage of the speed detector 8 is shown as (C) in the figure. The forward direction is shown as (+) and the reverse direction is shown as (-).

In FIG. 1A, the master arm 1 is assumed to be rotated clockwise and stopped at the position shown. When the grip 2 is gripped to operate the master arm 1, the switch provided on the grip 2 described above is turned on as shown in FIG. 3A, and the master arm 1 is stationary. That is, if the output voltage of the speed detector 8 is zero ... If the output voltage of the speed detector provided on each axis is zero ... As shown in FIG. Since it is supplied to the master arm 1 by 5, the rotation of the master arm 1 in the counterclockwise direction and the arrow a direction opposite to the direction of the previous operation can be performed lightly without requiring force. When the master arm 1 starts moving counterclockwise and the output voltage of the speed detector reaches + α, the supply of static friction compensation torque is stopped, but the friction of the bearing and other friction torque generating parts has already become dynamic friction. , Can be operated smoothly and smoothly. Grip 2 after stopping the operation
Since the motor actuator 5 supplies the static friction compensating torque -T in the reverse direction to the master arm 1 on condition that the master arm 1 stops when holding the switch, that is, when the switch is kept in the ON state, FIG. As shown in B), the master arm 1 can be rotated in the direction of arrow B, that is, in the clockwise direction without using force. After rotating the master arm 1 in the clockwise direction, the master arm 1 is stopped at the position shown in FIG. 7C, and then the rotation of the master arm 1 in the direction of arrow C in FIG. It can be done lightly without the need.

FIG. 4 is an explanatory view of the case where the static friction compensation torque is reset and generated in the same direction. When the grip 2 is grasped in FIG. 1 (A), the motor actuator 5 produces the forward static friction compensation torque + T. Therefore, the master arm 1 can be rotated in the arrow A direction, that is, the counterclockwise direction without requiring force, and when the master arm 1 moves and the output voltage of the speed detector 5 becomes + α, static friction is generated. Although the supply of the compensating torque T is cut off, the friction of each part generating the frictional resistance torque is changed from static friction to dynamic friction, so that the master arm 1 can be operated lightly.

When the master arm 1 is stopped and the grip 2 is still held, the motor actuator 5 supplies a static friction compensation torque -T in the opposite direction to the master arm 1, so that the arrow B in FIG. On the contrary, even if the master arm is further rotated in the same direction as the arrow A in FIG. 1A, that is, in the counterclockwise direction, the master arm 1 does not move or becomes very heavy. In this case, either weaken the gripping force of the grip 2 or release the hand to turn off the switch provided on the grip 2 and then re-grip the grip 2 to turn on the switch.
If this is done, the direction of the static friction compensation torque will be in the forward direction.
The master arm 1 can be lightly rotated in the clockwise direction opposite to the arrow B of (B) without requiring force.

[0016]

The static friction compensation torque is supplied to the master arm by the motor actuators of the respective axes of the multi-axis master / slave type servo manipulator. A large force for moving is not necessary, and a slight force can be applied to smoothly and lightly operate the master arm.

When the operation is stopped while holding the grip,
Since the static friction compensation torque is supplied in the direction opposite to the operation direction up to that point, operations that change the direction such as order, reverse, order, and reverse that are often performed when operating the master arm are extremely smooth. It can be done lightly, and when stopped, it can be stopped reliably.

Further, when the master arm is operated in the same direction after the stop as before, the master arm does not move or becomes very heavy. In that case, the master arm is stopped and the grip is grasped again or the grasping force is released. By turning off the switch provided on the grip and then turning it on again, it becomes possible to easily operate in the same direction.

Further, since the torque detector which is used in the past and which is apt to pick up noise and which is susceptible to interference of other axes and the amplifier which accompanies it are not required, the control circuit can be easily designed and the speed detector can be used. Is smaller than a torque detector and does not require an increase in width as in the case of torque detection. Therefore, it can be made compact as a whole and design, manufacture, and maintenance are easy, and it has many practical effects.

Since all the actuators used by the manipulator of the present invention are motors, they are described as torques, but even if they are applied to fluid pressure cylinders that perform linear motion by replacing them with forces, they are exactly the same. The effect of can be obtained.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a uniaxial master arm according to an embodiment of the present invention.

FIG. 2 is a diagram showing an embodiment of a grip portion of the present invention.

FIG. 3 is an operation explanatory diagram of one embodiment of the present invention.

FIG. 4 is an operation explanatory diagram of another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Master arm 2 ... Grip 3 ... Axis 8 ... Speed detector 10 ... Push button switch 11 ... Grip 12 ... Emitter 13 ... Photoreceiver 14 ... Emitter / receiver

Claims (2)

[Claims] 1. In a master arm of a multi-axis master / slave type servo manipulator, a motor actuator and a speed detector are provided for each axis of the master arm, and the grip of the master arm operates when the grip is gripped. A switch is provided and the output voltage when the master arm starts moving is set in advance in the speed setting device of the speed detector and this is set as the start confirmation speed, and the master arm is set in the torque setting device of the motor actuator. The static torque at the start of movement is set as static friction compensation torque, and static friction compensation in the direction opposite to the previous operation direction (forward direction) is provided on condition that the master arm is stationary when the grip switch is operated. The torque is supplied from the actuator to the master arm and the speed detection is performed. The master arm of a multi-axis master / slave type servo manipulator characterized in that the supply of this static friction compensation torque is stopped when the output of the output device reaches a set value. 2. A master arm of a multi-axis master / slave type servo manipulator is provided with a motor actuator and a speed detector for each axis of the master arm, and the grip of the master arm operates when gripping the grip. A switch is provided and the output voltage when the master arm starts moving is set in advance in the speed setting device of the speed detector and this is set as the start confirmation speed, and the master arm is set in the torque setting device of the motor actuator. The static torque at the start of movement is set as static friction compensation torque, and static friction compensation in the direction opposite to the previous operation direction (forward direction) is provided on condition that the master arm is stationary when the grip switch is operated. The torque is supplied from the actuator to the master arm and the speed detection is performed. When the output of the output device reaches the set value, the static friction compensation torque supply is stopped, and the static friction compensation torque is supplied in the forward direction by operating the grip switch. A multi-axis master / slave type servo characterized in that when the switch is turned off and then on again after being operated and stopped, the master arm is supplied with static friction compensation torque in the same direction as the forward direction. Manipulator master arm.