JP2002202820A - Reaction force control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To optionally set and vary characteristics of a reaction force applied to an input part. SOLUTION: This system is equipped with an actuator 1 which has a servomotor rotating a screw shaft of a ball screw mechanism and supplies a reaction force to the input part while displacing the input part by the relative movement between a screw shaft and a ball nut through the operation of the servomotor, a load cell 4d which outputs an external force signal showing the strength of the external force applied to the input part, a potentiometer 1g which outputs a position signal showing the position of the input part, a driver 2a which operates the servomotor so that the difference between a position command signal and the position signal is eliminated, a reaction force controller 2b which generates and outputs the position command signal according to the difference between the signal generated by adding a position signal made variable in value according to a reaction force/displacement gradient command signal, a speed signal found from the position signal through differentiation processing and made adjustable in value according to an attenuation factor command signal, and a stationary reaction force command signal and the external force signal, and a computer 3 which outputs the reaction force/displacement gradient command signal, the attenuation factor command signal, and stationary reaction force command signal according to arbitrary settings.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reaction force control system for applying a reaction force to an input section when an external force such as a human operation force is input to the input section.

[0002]

2. Description of the Related Art As a system as described above, for example, a system disclosed in Japanese Patent Publication No. Hei 7-111613 is known. This system is used in a simulated maneuvering device and is used for maneuver training. A ball screw having a ball nut drive-coupled to a take-off arm as an input unit connected to a simulation control function unit (simulation control stick) operated by a recipient and a screw shaft screwed to the ball nut And a servomotor for rotating a screw shaft of the ball screw mechanism, and a reaction force for applying a reaction force to the take-off arm while displacing the take-off arm by operation of the servomotor. A generation function unit, and a load cell that detects an operation force as an external force applied to the take-off arm and outputs an operation force signal indicating the magnitude of the operation force. And comprising a non-contact position sensor for outputting a position signal indicating the position by detecting the position of the take-off arm.

The conventional system further includes a spring force obtained by multiplying a current position based on a position signal from the non-contact position sensor by a predetermined spring coefficient and an equivalent speed described later by a predetermined friction coefficient. The steering reaction force is obtained by adding the frictional force and the like, and the driving force is obtained by subtracting the operation force based on the operation force signal from the load cell from the steering reaction force, and the driving force is integrated. Thus, a control function unit is provided for obtaining an equivalent speed and outputting a drive signal based on the equivalent speed to the servomotor.

[0004]

According to such a conventional system, a reaction force corresponding to parameters such as a predetermined spring coefficient and a predetermined friction coefficient can be applied to the take-off arm. Cannot be set arbitrarily or changed instantaneously or at any time.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a system which advantageously solves the above-mentioned problems, and a reaction force control system according to the present invention. Has a ball screw mechanism having a ball nut and a screw shaft screwed to the ball nut, and a servo motor for rotating the screw shaft of the ball screw mechanism, wherein the screw shaft is operated by the servo motor. A reaction force applying means for applying a reaction force to the input portion while displacing the input portion by relative movement with the ball nut, and an external force signal indicating a magnitude of the external force by detecting an external force applied to the input portion External force detecting means for detecting the position of the input section and outputting a position signal indicating the position of the input section, and a difference between the position command signal and the position signal. Means for operating the servo motor as described above, the position signal whose magnitude can be adjusted based on the reaction force / displacement gradient command signal, and a differential processing based on the position signal and a damping rate command signal. A reaction force that generates the position command signal in accordance with a difference between a speed signal whose magnitude can be adjusted and a signal obtained by adding a steady reaction force command signal and the external force signal, and outputs the position command signal Control means and arbitrarily set reaction force
Outputting the reaction force / displacement gradient command signal based on the displacement relationship, the decay rate command signal based on an arbitrarily set attenuation rate, and the steady reaction force command signal based on an arbitrarily set steady reaction force; And reaction force characteristic setting means.

In such a reaction force control system, the reaction force applying means rotates the screw shaft of the ball screw mechanism by the operation of the servomotor to relatively move the screw shaft and the ball nut screwed thereto. Applying a reaction force to the input unit while displacing the input unit, the external force detection unit detects the external force applied to the input unit and outputs an external force signal indicating the magnitude of the external force, and the input unit position detection unit Detects the position of the input section and outputs a position signal indicating the position of the input section, and the servo motor control means operates the servo motor so that the difference between the position command signal and the position signal is eliminated. The reaction force control means obtains the magnitude by adjusting the position signal based on the reaction force / displacement gradient command signal and the position signal, and adjusts the magnitude based on the attenuation rate command signal. Speed signal, a signal obtained by adding a steady reaction force command signal, and the position command signal in accordance with a difference between the external force signal and the position command signal, and outputs the position command signal. The reaction force / displacement gradient command signal based on an arbitrarily set reaction force-displacement relationship, the decay rate command signal based on an arbitrarily set damping rate, and the arbitrarily set stationary reaction force. And a stationary reaction force command signal.

According to a second aspect of the present invention, there is provided a reaction force control system comprising: a rotary shaft drivingly coupled to an input unit; and a servomotor for rotating the rotary shaft, wherein the rotation of the rotary shaft by the operation of the servomotor is performed. Reaction force applying means for applying a rotational reaction force to the input portion while rotating the input portion by rotating the shaft, and detecting an external force applied to the input portion and outputting an external force signal indicating the magnitude of the external force. An external force detecting means, an input part position detecting means for detecting a rotational position of the input part and outputting a position signal indicating the rotational position of the input part, and an input part detecting means for eliminating a difference between a position command signal and the position signal. Servo motor control means for operating the servo motor; the position signal whose magnitude can be adjusted based on the reaction force / displacement gradient command signal; The position command signal is generated according to the difference between the speed signal whose magnitude can be adjusted based on the signal, the signal obtained by adding the steady reaction force command signal, and the external force signal, and the position command signal is output. Reaction force control means, the reaction force / displacement gradient command signal based on an arbitrarily set reaction force-displacement relationship, and the decay rate command signal based on an arbitrarily set attenuation rate. Reaction force characteristic setting means for outputting the steady reaction force command signal based on the steady reaction force,
It is equipped with.

In such a reaction force control system, the reaction force applying means rotates the rotation shaft by the operation of the servomotor, thereby rotating and displacing the input portion which is drive-coupled to the rotation shaft, to the input portion. Gives a reaction force, and the external force detection means
Detecting an external force applied to the input unit and outputting an external force signal indicating the magnitude of the external force; input unit position detecting means detecting a position of the input unit and detecting a position signal indicating the position of the input unit; And the servo motor control means operates the servo motor so that there is no difference between the position command signal and the position signal, and the reaction force control means adjusts the magnitude based on the reaction force / displacement gradient command signal. The enabled position signal, and a speed signal whose magnitude can be adjusted based on the attenuation rate command signal obtained by differentiating from the position signal,
The position command signal is generated in accordance with a difference between the signal obtained by adding the steady reaction force command signal and the external force signal, and the position command signal is output. The reaction force / displacement gradient command signal based on the force-displacement relationship, the decay rate command signal based on an arbitrarily set attenuation rate, and the steady reaction force command signal based on an arbitrarily set steady reaction force. Output each.

Therefore, according to the reaction force control system of the present invention, the reaction force-displacement relationship, the damping rate, and the steady reaction force are arbitrarily set, and the reaction force characteristic setting means is set. By giving, the characteristic of the reaction force applied to the input unit can be arbitrarily set, and the characteristic of the reaction force can be changed instantaneously or at any time and easily according to the change of the surrounding situation.

In the reaction force control system according to the present invention, the position signal and the external force signal are inputted, and the actual displacement of the input section and the actual reaction force at that time are inputted. And actual displacement / actual force display means for displaying the magnitude of the above. The actual operation status of the system can be easily monitored.

[0011]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a configuration diagram showing one embodiment of a reaction force control system according to the present invention. The system of this embodiment includes a reaction force generation actuator 1, a reaction force control unit 2, a reaction force-displacement. And a relation instruction computer 3.

The reaction force generating actuator 1 here
FIG. 3A is a plan view and a side view of FIGS.
As shown in the perspective view of FIG.
The working device 4 includes an upper arm 4a supported by a frame (not shown), a lower arm 4b having a base end swingably supported at the lower end of the upper arm 4a, A rod-shaped grip 4c as an input portion, which is disposed so as to protrude horizontally from the side surface of the tip of the lower arm 4b, and the grip 4c housed in the grip 4c and the tip of the lower arm 4b. And a load cell 4d as external force detecting means for detecting the magnitude of an external force applied to the grip 4c, and an instrument mounting portion 4e swingably supported at the tip of the lower arm portion 4b. The lower arm 4b
A leaf spring 4f as a cushioning material for connecting the instrument mounting portion 4e to the distal end of the lower arm 4b, and a base end of the lower arm 4b and a lower end of the upper arm 4a, which are swingably connected to each other. It has two link members 4g and 4h that are swingably connected and form a four-bar link with the base end of the lower arm 4b and the lower end of the upper arm 4a.

The above reaction force generating actuator 1
A base 1a swingably supported by the upper arm 4a, a screw shaft 1b housed in the base 1a and rotatably supported by the base 1a, and a base 1a disposed parallel to the screw shaft 1b. The servomotor 1c supported by the base and the base 1
a ball train (ball-circulating nut) which is housed in the motor shaft 1a and drives and couples the output shaft of the servomotor 1c and the screw shaft 1b to the screw shaft 1b; 1) and a cylindrical operation in which the ball nut 1e is fixed to one end and the screw shaft 1b is slidably accommodated, and the base 1a is supported by the base 1a so as to be movable forward and backward in the axial direction of the screw shaft 1b. Rod 1f
And a linear actuating potentiometer 1g fixed to the base 1a and detecting the position of the operating rod 1f with respect to the base 1a. The distal end of the operating rod 1f is connected to the two links. The members 4g and 4h are swingably connected to a connecting portion between the members.

The reaction force generating actuator 1 rotates the screw shaft 1b by the operation of the servomotor 1c to move the operating rod 1f together with the ball nut 1e with respect to the base 1a in the axial direction of the screw shaft 1b. 5, the link member 4g connected to the operating rod 1f is swung with respect to the upper arm portion 4a, and the operating rod 1f is moved.
Move another link member 4h connected to
The lower arm 4b connected to the link member 4h is connected to the upper arm 4
a, thereby displacing the grip 4c with respect to the upper arm 4a, and displacing the instrument mounting portion 4e with respect to the upper arm 4a, as described later. As a result, the operation of the servomotor 1c is controlled to apply a reaction force to the grip 4c, so that it functions as a reaction force applying means. The potentiometer 1g is
Grip 4c via lower arm 4b and link member 4h
Function as input unit position detecting means.

The reaction force control unit 2 here
Has an actuator position control driver 2a and a reaction force controller 2b, as shown in FIG. 1 and FIG. 6, and the actuator position control driver 2a is configured to receive a position command signal Spc from the reaction force controller 2b and the potentiometer. 1g, the motor drive current Imd in the direction in which the signal difference disappears is output to the servomotor 1c until the signal difference disappears, and the reaction force controller 2b receives the signal from the potentiometer 1g from the potentiometer 1g until the signal difference disappears. Send the position feedback signal Spf. Since the actuator position control driver 2a is an ordinary driver, the details of the circuit configuration are omitted.

The reaction force controller 2b, as shown in FIG. 7, shows a reaction force corresponding to the magnitude of the external force F applied to the grip 4c from the bridge circuit of the strain gauge in the load cell 4d. A dynamic distortion amplifier 2c that amplifies the distortion signal Sfs and outputs a reaction force feedback signal Sff as an external force signal; and a differentiation circuit 2d that differentiates the position feedback signal Spf from the actuator position control driver 2a and outputs a velocity signal Ss. A variable gain amplifying circuit 2e for amplifying the position feedback signal Spf with a gain corresponding to the reaction force / displacement gradient command signal Sac from the reaction force-displacement relation indicating computer 3, and the speed signal Ss also for the reaction force-displacement. A variable gain amplifier circuit 2f for amplifying with a gain corresponding to the attenuation rate signal Sdc from the relation indicating computer 3; They variable gain amplifier circuit 2e, 2
From the reaction force command signal Sfc obtained by adding the output signal of f and the steady reaction force command signal Ssfc from the reaction force-displacement relation indicating computer 3, a reaction force feedback signal Sff amplified by the dynamic strain amplifier 2c is obtained. An integral amplifier circuit 2g is provided to obtain a position command signal Spc that integrates the subtracted output signal to give a predetermined reaction force based on a reaction force / displacement gradient, a steady reaction force, and a damping rate, which will be described later.

The reaction force controller 2b here
Specifically, IC1 (using A, C, and D sections), I
C2 (uses A to D), IC3 (uses A and B),
It is compactly configured by an analog circuit using four ICs of IC4 (using A to D), and these ICs are directly connected to the power supply circuit shown in FIG. The power is supplied through a smoothing circuit shown in FIG.
Power is supplied from the power supply circuit shown in FIG.

Further, the reaction force-displacement relation indicating computer 3 here is constituted by an ordinary personal computer, and operates based on a program given in advance, and as shown in FIG. ) And the magnitude of the reaction force given to the grip 4c (for example, a relational expression or tabular data), the magnitude of the steady reaction force given to the grip 4c, and the magnitude of the damping rate of the reaction force, respectively. In addition to memorizing the change, the relationship between the displacement and the reaction force, the magnitude of the steady-state reaction force and the magnitude of the damping rate are appropriately changed by the user's operation, and each position obtained from the relationship between the displacement and the reaction force From the gradient (increase rate) of the reaction force at step S1 and the position feedback signal Spf sent from the reaction force controller 2b. / Acceleration gradient command signal Sac, and outputs the reaction force / displacement gradient command signal Sac to the reaction force controller 2b. The force command signal Ssfc and the damping rate signal Sdc are output to the reaction force controller 2b.

In addition, the reaction force-displacement relation indicating computer 3 generates a reaction force feedback signal Sff and a position feedback signal Sff sent from the reaction force controller 2b.
The actual position (displacement) of the grip 4c and the magnitude of the actual reaction force at the current time point are calculated from pf, and the data is displayed on the screen of the screen display device of the computer 3.

Therefore, according to the reaction force control system of this embodiment, the reaction force-displacement relationship, that is, the virtual spring coefficient, the reaction force damping rate according to the displacement speed, and the steady reaction force, that is, the virtual pretension value, are calculated. By providing the reaction force-displacement relation instructing computer 3 arbitrarily, the characteristics of the reaction force applied to the grip 4c can be arbitrarily set, thereby realizing a reaction force generator with a virtual spring and a virtual damper. In addition, the characteristics of the reaction force can be instantaneously and easily changed in response to changes in the surrounding conditions.

Further, according to the reaction force control system of this embodiment, the reaction force-displacement relation indicating computer 3 displays the actual position (displacement) of the grip 4c at the present time on the screen of the screen display device and the actual position. Since the magnitude of the reaction force is displayed, the actual operation status of the system can be easily monitored.

According to the reaction force control system of this embodiment, for example, a luggage holder or the like is attached to the tool attachment portion 4e of the working device 4, and a person manually operates the grip 4c to lift the luggage. In this case, while lifting to a certain height, the reaction force generating actuator 1 applies a lifting force close to the load of the load to the lower arm 4b, and the reaction force (operation force) applied to the hand from the grip 4c is greater than the load of the load. Reaction force control can be performed such that the reaction force (operating force) is gradually increased when the object is lifted to a certain height or more, so that the object is not raised too high.

FIGS. 9 to 14 show another embodiment of the reaction force control system according to the present invention. The reaction force control system according to this embodiment comprises two reaction force generation actuators 5 and 6.
9 and a reaction force control unit 2 and a reaction force-displacement relation indicating computer 3 having the same configuration as those in the previous embodiment. As shown in the figure, the operation simulation device 7 is provided.

The driving simulation device 7 simulates a driver's seat of a vehicle, and includes an instrument panel 7a, a seat 7b on which a person can sit, a steering wheel 7c as an input unit, and a brake pedal 7 as an input unit.
d (see FIGS. 13 and 14), an accelerator pedal (not shown), and a support member 7e below the instrument panel 7a. Force generating actuator 5
Is coupled to the steering wheel 7c to apply a steering reaction to the steering wheel 7c, and another reaction force generating actuator 6 is coupled to the brake pedal 7d and plays a role of applying a depressing reaction to the brake pedal 7d. . And the reaction force-displacement relation indicating computer 3
Displays the screen display device on the instrument panel 7
a.

That is, the reaction force generating actuator 5
As shown in the side views of FIGS. 9 and 10, the front view of the steering wheel 7c in the mounted state of FIG. 11, and the cross-sectional view seen from above in FIG. Base 5a and two rotations accommodated in the base 5a and rotatably supported by the base 5a and coupled to each other on the same axis via a coupling 5b and a load cell 5c as external force detecting means. Shafts 5d and 5e, and a servomotor with a reduction gear 5 arranged in parallel with the rotation shafts 5d and 5e and supported by a base 5a.
f and the servo motor 5 housed in the base 5a.
and a belt-type transmission mechanism 5g for drivingly connecting the output shaft of the shaft f to the one of the rotating shafts 5e, and reducing the rotation of the rotating shaft 5d to 1/2 while being driven and connected to the other rotating shaft 5d. A rotation restricting mechanism 5h for restricting the rotation of the rotary shaft 5 by a stopper so that the rotation can be performed by approximately one rotation; A potentiometer 5h is provided, and the tip of the other rotary shaft 5d is connected to the steering wheel 7c.

The reaction force generating actuator 5 rotates the rotating shafts 5d and 5e by operating the servo motor 5f to rotate the steering wheel 7c, and the reaction force control unit 2 and the reaction force −
Since the operation of the servo motor 5f is controlled by the displacement relation instruction computer 3 to apply a reaction force to the steering wheel 7c, it functions as a reaction force applying means. The potentiometer 5h detects the rotational position of the steering wheel 7c via the rotating shafts 5d and 5e and inputs the rotational position to the reaction force control unit 2, so that the potentiometer 5h functions as an input unit position detecting unit.

The other reaction force generating actuator 6 is a perspective view from the front side when the brake pedal 7d is mounted in FIG. 13 and FIG. 9 when the brake pedal 7d is mounted in FIG. As shown in the side view seen from the opposite side, a base 6a fixedly supported on the bottom plate portion of the support member 7e, and the base 6a housed in the base 6a
a, a screw shaft (not shown) rotatably supported by a, a servomotor 6b disposed in parallel with the screw shaft and supported by a base 6a, and an output shaft of the servomotor 6b housed in the base 6a. A belt-type transmission mechanism (not shown) for drivingly coupling the screw shaft, a ball nut (ball circulation type nut) not shown which is screwed to the screw shaft to form a ball screw mechanism, and the ball nut is fixed. An operating member (not shown) supported on the base 6a so as to be able to advance and retreat in the axial direction of the screw shaft, and a linear actuation potentiometer fixed to the base 6a and detecting the position of the operating member with respect to the base 6a. 6c, and the brake pedal 7d can be angle-adjusted to the side of the operating member via a load cell 6d as an external force detecting means. It has been fixed.

The reaction force generating actuator 6 rotates the screw shaft by the operation of the servo motor 6b to move the operating member together with the ball nut in the axial direction of the screw shaft with respect to the base 6a, thereby causing a brake pedal 7d. Is linearly moved, and the operation of the servo motor 6b is controlled by the reaction force control unit 2 and the reaction force-displacement relation instruction computer 3 in the same manner as in the previous embodiment.
Since the reaction force is applied to the brake pedal 7d, it functions as a reaction force applying means. And the potentiometer 6c
Since the position of the brake pedal 7d is detected and input to the reaction force control unit 2 via the operating member,
It functions as input unit position detection means.

Therefore, according to the reaction force control system of this embodiment, the reaction force-displacement relationship, that is, the virtual spring coefficient, the reaction force damping rate corresponding to the displacement speed, and the steady reaction force, that is, the virtual pretension value, are calculated. By providing the reaction force-displacement relation indicating computer 3 with any setting, the characteristics of the reaction force given to the steering wheel 7c and the brake pedal 7d can be set arbitrarily. A reaction force generator can be realized, and the characteristics of the reaction force can be changed instantaneously or at any time and easily according to changes in the surrounding conditions.

Further, according to the reaction force control system of this embodiment, the reaction force-displacement relation indicating computer 3 displays the current steering wheel 7c on the screen of the screen display device installed on the instrument panel 7a. In addition, since the actual position (displacement) of each brake pedal 7d and the magnitude of the actual reaction force are displayed, the actual operation state of the system can be easily monitored.

According to the reaction force control system of this embodiment, for example, the steering wheel 7c according to the driving ability or preference of the person using the driving simulation device 7, or according to the characteristics of various actual types of vehicles.
And the characteristics of the reaction force applied to the brake pedal 7d can be set arbitrarily, and changes in the road surface conditions during running of the vehicle being simulated (for example, when rain starts)
The characteristics of the reaction force applied to the steering wheel 7c and the brake pedal 7d can be changed instantaneously and at any time according to the conditions, etc., so that a situation very close to the actual driving situation can be simulated.

Although the present invention has been described with reference to the illustrated examples, the present invention is not limited to the above-described examples. For example, in the above embodiment, the load cell for detecting the external force is provided on the operating rod of the reaction force generating actuator. May be. Further, the external force applied to the input unit is not limited to the operation force of a person, and may be a force applied from the wheels to the suspension device by running of the vehicle.

Further, the reaction force control system of the present invention can be applied to a reaction force feedback to an operator in a remote control system such as a robot, for example, thereby enabling accurate work and sensibly grasping a load. In addition, the present invention is also applicable to a case where it is necessary to maintain a constant thrust regardless of a change in load with a press machine or the like, or a variable characteristic suspension device controlled by a virtual spring and a virtual damper. be able to.

Further, the reaction force control system of the present invention
The present invention can also be applied to a training machine, and can apply a load while arbitrarily changing a preset size according to a person to be trained.

The reaction force control system according to the present invention
It can be applied to sensation game machines, etc., can apply a preset force to the operator, and can control sensation game machines to simulate various vehicles by applying the above-mentioned variable characteristic suspension device. You can also.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of a reaction force control system of the present invention.

FIGS. 2A and 2B are a plan view and a side view showing a working device provided with a reaction force generating actuator of the reaction force control system of the embodiment.

FIG. 3 is a perspective view showing a working device provided with a reaction force generating actuator of the reaction force control system of the embodiment together with a model of an operator.

FIG. 4 is a cross-sectional view illustrating a working device provided with a reaction force generating actuator of the reaction force control system according to the embodiment.

FIG. 5 is a side view showing an operation state of a reaction force generating actuator of the reaction force control system of the above embodiment and a working device provided with the same.

FIG. 6 is a block diagram illustrating a configuration of a reaction force control unit of the reaction force control system of the embodiment.

FIG. 7 is a configuration diagram showing a circuit configuration of a reaction force controller of a reaction force control unit of the reaction force control system of the embodiment.

FIGS. 8A, 8B and 8C are configuration diagrams showing a power supply circuit for supplying power to a reaction force control unit and a load cell of the reaction force control system of the embodiment.

FIG. 9 is a side view showing a driving simulation apparatus provided with another embodiment of the reaction force control system of the present invention, together with a model of an operator.

FIG. 10 is a side view showing one of the reaction force generating actuators of the reaction force control system according to the embodiment, with a steering wheel mounted.

FIG. 11 is a front view showing the one reaction force generating actuator in a state where a steering wheel is mounted.

FIG. 12 is a cross-sectional view showing the one reaction force generating actuator with a steering wheel mounted.

FIG. 13 is a front perspective view showing the other reaction force generating actuator of the reaction force control system of the above embodiment with a brake pedal mounted.

14 is a side view showing the other reaction force generating actuator of the reaction force control system according to the embodiment when the brake pedal is mounted, as viewed from the side opposite to FIG. 9;

[Explanation of symbols]

 1,5,6 Reaction Force Generating Actuator 1c, 5f, 6b Servo Motor 1g, 5i, 6c Potentiometer 2 Reaction Force Control Unit 2a Actuator Position Control Driver 2b Reaction Force Controller 3 Reaction Force-Displacement Related Instruction Computer 3 4 Working Device 4a, 5c, 6d Load cell 7 Operation simulation device 7a Instrument panel 7b Seat 7c Steering wheel 7d Brake pedal 7e Support member

Claims (3)

[Claims] A ball screw mechanism having a ball nut and a screw shaft screwed into the ball nut; and a servomotor for rotating the screw shaft of the ball screw mechanism.
A reaction force applying means for applying a reaction force to the input unit while displacing the input unit by a relative movement between the screw shaft and the ball nut by the operation of the servomotor; and detecting an external force applied to the input unit. External force detection means for outputting an external force signal indicating the magnitude of the external force, input unit position detection means for detecting the position of the input unit and outputting a position signal indicating the position of the input unit, and a position command signal. Servo motor control means for operating the servo motor so as to eliminate the difference from the position signal; a position signal whose magnitude can be adjusted based on a reaction force / displacement gradient command signal; and a differential processing based on the position signal. The speed signal obtained and the magnitude can be adjusted based on the damping rate command signal, a signal obtained by adding a steady reaction force command signal, and the position command signal according to a difference between the external force signal and the signal. Reaction force control means for generating and outputting the position command signal; the reaction force / displacement gradient command signal based on an arbitrarily set reaction force-displacement relationship; and the attenuation based on an arbitrarily set attenuation rate A reaction force control system comprising: a ratio command signal; and a reaction force characteristic setting unit that outputs the steady reaction force command signal based on an arbitrarily set steady reaction force. 2. An input unit, comprising: a rotating shaft drivingly coupled to an input unit; and a servomotor for rotating the rotating shaft, wherein the input unit is rotated while the input unit is rotationally displaced by rotation of the rotating shaft by operation of the servomotor. A reaction force applying unit that applies a rotational reaction force to the unit, an external force detection unit that detects an external force applied to the input unit, and outputs an external force signal indicating the magnitude of the external force, and detects a rotational position of the input unit. An input part position detecting means for outputting a position signal indicating a rotational position of the input part; a servo motor control means for operating the servo motor so that a difference between a position command signal and the position signal is eliminated; A position signal whose magnitude can be adjusted based on a displacement gradient command signal, and a velocity signal whose magnitude can be adjusted based on a decay rate command signal obtained by differentiating from the position signal. Reaction force control means for generating the position command signal in accordance with a difference between a signal obtained by adding a steady reaction force command signal and the external force signal, and outputting the position command signal, and an arbitrarily set reaction force Outputting the reaction force / displacement gradient command signal based on the displacement relationship, the decay rate command signal based on an arbitrarily set damping rate, and the steady reaction force command signal based on an arbitrarily set steady reaction force; A reaction force control system comprising: 3. An actual displacement / actual force display means for receiving the position signal and the external force signal and displaying the magnitude of the actual displacement of the input section and the actual reaction force at that time. The reaction force control system according to claim 1, wherein: