JP2006218573A - Operation device, operation adjustment method of operation element, and its program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology of causing an appropriate operation feeling irrespective of operation steps when an operation element is operated. <P>SOLUTION: The operation device is equipped with the operation element operated by a person, an operation force detection means for detecting the operation force applied to the operation element by the person, and a motion adjustment means for converting the motion of an object, which is placed under the environment of causing the resistance force proportional to a speed on the object, caused when the operation force detected by the operation force detection means is applied to the object into the motion of the operation element. The smaller the operation force detected by the operation force detection means is, the greater the proportional coefficient set by the motion adjustment means to be multiplied by the speed for calculating the resistance force is. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a technique for adjusting the operation of an operator operated by a person using an actuator. In particular, the present invention relates to a technique for controlling an actuator so that good operability can be obtained by applying an appropriate reaction force (for example, response) from a manipulator to the man when an manipulator is applied to the manipulator.

Devices such as a power steering device for an automobile and a device that assists in carrying heavy objects have been developed by assisting human operations by adjusting the operation of a manipulator operated by a person with an actuator. In this kind of technology, between the operation force that a person applies to the operation element and the movement of the operation element that is realized as a result,
M.a + D.v + K. (P-po) = f (1)
It is known that when this relationship is established, a person can obtain a good feeling of operation and the operability is improved. Here, a is the acceleration vector of the operator, v is the velocity vector of the operator, p is the position vector of the operator, and po is a constant vector. M is a proportional coefficient (proportional matrix) with respect to the acceleration of the operating element, and corresponds to an inertia coefficient (inertial matrix) reproduced by the operating element. D is a proportional coefficient (proportional matrix) with respect to the speed of the operation element, and corresponds to a viscosity coefficient (viscosity matrix) reproduced by the operation element. K is a proportional coefficient (proportional matrix) with respect to the position of the operation element, and corresponds to a rigidity coefficient (rigidity matrix) reproduced by the operation element. po is a constant vector, which is a position vector indicating the equilibrium position of the stiffness characteristic. f is a human operation force vector. The operational feeling can be adjusted by adjusting the proportional coefficients M, D, and K in the above equation (1).

A technique for adjusting the operation of the operator so as to satisfy the above-described expression (1) is a well-known technique called impedance control. According to the impedance control, the motion of the object placed in the environment where the resistance force (viscous resistance force) proportional to the speed acts can be realized as the motion of the operation element. In impedance control, “torque-based impedance control” and “position-based impedance control” are known.
In “torque-based impedance control”, the actuator is based on the resultant force of the force required for the movement realized by the operator and the force required to cancel the inertia and frictional resistance of the movement mechanism of the operator. Adjust the output. Details of “torque-based impedance control” are described in Non-Patent Document 1, for example.
In “position-based impedance control”, the motion realized in the operator is calculated, and the position of the operator is adjusted based on the position where the motion is realized. Details of “position-based impedance control” are described in Non-Patent Document 2, for example.
Tsuneo Yoshikawa “Robot Control Fundamentals” Corona, 1988 Kazuhiro Komine, Katsuhisa Furuta, Tatsuaki Yokoyama, “Virtual Internal Model Tracking Control System for Robots-Application to Mechanical Impedance Control”, Transactions of the Society of Instrument and Control Engineers, Vol. 24, No. 1, pp. 55-62

A technique using impedance control is disclosed in Patent Document 1. The apparatus of Patent Document 1 includes a movable body that supports a heavy object and an actuator that moves the movable object, and an operation force that an operator applies to the movable body, and a movement of the heavy object that is realized by the operation force and the actuator. The output of the actuator is adjusted so that the above equation (1) holds.
According to Patent Document 1, the work of transporting heavy objects is roughly divided into a plurality of work stages, and at the time of positioning for moving a heavy object finely, the proportional coefficient M for acceleration is reduced while the proportional coefficient D for speed is increased. It is reported to be effective.
JP 2001-75649 A

According to the technique of Patent Document 1, it is possible to realize an appropriate operational feeling according to the work stage of the transfer work. However, when this technique is used, it is necessary to determine the work stage.
The present invention provides a technique for imparting an appropriate operational feeling to an operator without determining the work stage.

  The present invention can be embodied in an operating device that adjusts the operation of an operator operated by a person following a human operation. This operating device has an operating element operated by a person, an operating force detecting means for detecting an operating force applied by the person to the operating element, and an operating force detected by the operating force detecting means having a resistance force proportional to the speed. It is provided with a motion adjusting means for realizing the motion generated in the object when it is applied to the object placed in the working environment as the motion of the operation element. The movement adjusting means is characterized in that the smaller the operating force detected by the operating force detecting means, the larger the proportional coefficient used when determining the resistance force by multiplying the speed.

In this operating device, the relationship of the above expression (1) can be established between the operating force applied by the person to the operating element and the movement of the operating element that is realized as a result. At this time, if the proportionality coefficient M for acceleration and the proportionality coefficient D for speed are made constant and the proportionality coefficient K for position is set to zero, the operating force f applied by the person to the operating element and the resulting operating element speed v Changes as shown in FIG. FIG. 5 shows the operation of moving the stationary operating element to the target position to make it stationary. In FIG. 5, M · a indicates the inertia term in the equation (1), D · v indicates the viscosity term in the equation (1), and the sum M · a + D · v of both is equal to the operating force f. Become. As shown in FIG. 5, in the latter half of positioning the operating element while decelerating, the direction in which the operating force f is applied and the moving direction of the operating element are reversed. In this case, the operational feeling at the stage of positioning while decelerating becomes worse. With respect to this problem, in the technique of Patent Document 1, the inertia term M · a is reduced or the viscosity term D · v is increased at the positioning stage.
As shown in FIG. 5, when a person operates the operating element, the operating element is accelerated by a large operating force f in the initial movement stage, and is decelerated by loosening the operating force f in the positioning stage. At the time of deceleration, if the viscosity term D · v is not sufficiently large, the speed v of the operating element is not sufficiently reduced, and it becomes necessary to apply the operating force f in the opposite direction.
Therefore, in the operating device according to the present invention, when the operating force f applied by the person to the operating element is small, the proportional coefficient D with respect to the speed is increased. Thereby, when a person loosens the operation force f and decelerates the operation element, the operation element is sufficiently decelerated. At this time, by loosening the operation force f, a person can obtain an operation feeling that allows a strong braking force to be applied to the operation element, making it easier to operate the operation element at the positioning stage.
According to the operating device of the present invention, it is possible to give a good operational feeling to the operator without discriminating the work stage.

The motion adjusting means is a motion calculating means for calculating a motion generated in the object when the operating force detected by the operating force detecting means is applied to the object in an environment where a resistance force proportional to the speed acts. It is preferable to include an actuator that realizes the motion calculated by the motion calculation means as the motion of the operator. In this case, the motion calculation means may set a larger proportional coefficient for use in calculating the resistance force by multiplying the speed as the operation force detected by the operation force detection means is smaller.
Accordingly, it is possible to adjust the operation of the operation element by adopting position-based impedance control.

Speed control means for detecting the speed of the operating element may be added to the operating device. In this case, the motion calculation means corrects the reference value stored in the storage means to a larger value as the operation force detected by the operation means and the storage means storing the reference value of the proportional coefficient is smaller. A coefficient correction means, a resistance force calculation means for calculating the resistance force by multiplying the proportionality coefficient corrected by the coefficient correction means by the speed of the operator detected by the speed detection means, and an operation detected by the speed detection means A target that calculates the target speed of the operating element by taking into account the speed change resulting from the resultant force of the operating force detected by the operating force detection means and the resistance force calculated by the resistance force calculating means. It is preferable to provide a speed calculation means.
Each component of the motion calculation means can be constituted by a linear element such as a resistor or a capacitor, or an arithmetic circuit in which an operational amplifier is combined therewith. All of the motion calculation means can be constituted by analog electronic circuits, and the operating device can be constituted at low cost.

If a sensor or the like for detecting any of the position, speed, acceleration and the like of the operating element is added to the operating device, the movement of the operating element can be detected. In an operating device with a means to detect the movement of the operating element, the movement adjusting means realizes the movement detected by the movement detecting means to the movement of an object in an environment where a resistance force proportional to the speed acts. The force calculated by the force calculation means from the force calculation means for calculating the force required to be applied to the object and the force required for realizing the motion detected by the motion detection means to the motion of the operation element. It is preferable to provide an actuator that applies the reduced force to the operation element. In this case, the force calculation means may set a larger proportional coefficient for use in calculating the resistance force by multiplying the speed as the operation force detected by the operation force detection means is smaller.
Accordingly, it is possible to adjust the operation of the operation element by adopting torque-based impedance control.

The present invention can also be embodied in a method of adjusting the operation of an operator operated by a person using an actuator. In this method, an operation force detection process for detecting an operation force applied by a person to an operation element, and an operation force detected in the operation force detection process are applied to an object placed in an environment where a resistance force proportional to the speed acts. A motion adjustment step of controlling the actuator to realize the motion generated in the object when it is added to the motion of the operator. In the motion adjustment step, the smaller the operation force detected in the operation force detection step, the larger the proportional coefficient used when calculating the resistance force by multiplying the speed.
According to this method, it is possible to give a good operational feeling to the operator without determining the work stage.

The present invention can also be embodied in a program that is executed by an electronic computer included in an operation device that adjusts the operation of an operator operated by a person using an actuator. This program is generated when an operation force applied by a person to an operating element is input to an object placed in an environment where a resistance force proportional to the speed is applied. The computer is caused to execute a motion adjustment process that realizes the motion to the motion of the operator by controlling the actuator. The motion adjustment process is characterized in that the smaller the input operating force is, the larger the proportionality coefficient used when calculating the resistance force by multiplying the speed.
By using this program, it is possible to give an appropriate operational feeling to the operator without discriminating the work stage.

  According to the present invention, it is possible to embody an operation device having a good operational feeling. There is no need to determine the work stage and change the coefficients.

A preferred embodiment for carrying out the present invention will be described.
(Mode 1) The work support device includes an operator operated by an operator, a first actuator that displaces the operator in the x direction, a second actuator that displaces the operator in the y direction, and an operator in the z direction. A third actuator to be displaced is provided.
(Mode 2) The work support device includes a force sensor that measures the force applied by the operator to the operator. The force sensor distinguishes the force applied by the operator to the operation element into six directions including the x direction, the y direction, the z direction, and the x direction, the y axis direction, and the z axis direction. Can be detected.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an overall view of a device 2 (hereinafter abbreviated as a work assist device) 2 that assists a worker in transporting heavy objects. FIG. 2 shows an electrical configuration of the work assisting device 2.
1 and 2 is used in a process of assembling an instrument panel (hereinafter abbreviated as instrument panel) 400 of an automobile in a body (not shown) of the automobile at a manufacturing site of the automobile. . The worker in this process carries out the operation of transporting the instrument panel 400 into the automobile body, positioning it, and fixing it to the automobile body. The operator fixes the instrument panel 400 to the work auxiliary device 2, and carries and positions the instrument panel 400 via the work auxiliary device 2. As will be described in detail later, the work assisting device 2 adjusts the operation of the operation element 4 by an actuator following an operation that a person applies to the operation element 4. As a result, the operator can transport the instrument panel 400 with a force when transporting an object that is lighter than the instrument panel 400.

  As shown in FIG. 1, the work assisting device 2 includes a pair of fixed rails 8 a and 8 b, a first movable body 10 that can slide along the longitudinal direction of the fixed rails 8 a and 8 b, and the first movable body 10. The second movable body 20 is slidable along the longitudinal direction, and the third movable body 30 is slidable along the longitudinal direction of the second movable body 20. Hereinafter, the longitudinal direction of the fixed rails 8a and 8b is the x direction, the longitudinal direction of the first movable body 10 is the y direction, and the longitudinal direction of the second movable body 20 is the z direction. The x direction, the y direction, and the z direction are substantially orthogonal to each other. An instrument panel support 40 that can support the instrument panel 400 is attached to the third movable body 30. The instrument panel support 40 is provided with a fixing portion 46 for fixing the instrument panel 400 so as to be detachable. The work assisting device 2 is configured such that the third movable body 30 can freely move within a predetermined movable space, and the instrument panel 400 supported via the instrument panel support 40 can be freely moved. It is configured as follows.

As shown in FIGS. 1 and 2, the work auxiliary device 2 includes a first actuator 12 that slides the first movable body 10 along the x direction, and a second actuator that slides the second movable body 20 along the y direction. 22, a third actuator 32 is provided for sliding the third movable body 30 along the z direction.
The work assisting device 2 includes a force sensor 6 fixed to the third movable body 30 and an operation element 4 provided on the force sensor 6. When the operator transports the instrument panel 400 via the work assistant device 2, the operator operates the operator 4 to transport the instrument panel 400. The force sensor 6 detects an operation force applied to the operator 4 by the operator. The force sensor 6 can detect the operator's operation force in the x direction, the y direction, the z direction, and the forces in the six directions including the direction around the x axis, the direction around the y axis, and the direction around the z axis.
As shown in FIG. 2, the work auxiliary device 2 includes a first position sensor 16 that detects the position of the first movable body 10 in the x direction and a second position sensor that detects the position of the second movable body 20 in the y direction. 26 and a third position sensor 36 for detecting the position of the third movable body 30 in the z direction. The operation element 4 is fixed to the third movable body 30, the x-direction position of the operation element 4 is detected by the first position sensor 16, the y-direction position is detected by the second position sensor 26, and the z-direction position is the third position. It is detected by the position sensor 36.
The work assisting device 2 includes a control unit 60 that controls operations of the first actuator 12, the second actuator 22, and the third actuator 32.

  As shown in FIG. 2, the control unit 60 includes a first driver 14 that controls the first actuator 12, a second driver 24 that controls the second actuator 22, and a third driver 34 that controls the third actuator 32. I have. In addition, a processing unit 62 that gives commands to the drivers 14, 24, and 34, an operation panel 64 connected to the processing unit 62, and the like are provided. The processing unit 62 includes an electronic computer. The operator operates the operation panel 64 to input an instruction to the processing unit 62 and adjust control parameters. The operation panel 64 displays information from the processing unit 62 to the operator.

The force sensor 6 is connected to the processing unit 62. The processing unit 62 detects the operation force f applied by the operator to the operation element 4 from the output signal of the force sensor 6.
The first position sensor 16, the second position sensor 26, and the third position sensor 36 are connected to the processing unit 62. The processing unit 62 can detect the position p: (x, y, z) of the operation element 4 from the output signals of the position sensors 16, 26 and 36. Further, the processing unit 62 determines the speed v of the operating element 4: (dx / dt, dy / dt, dz / dt) and the acceleration a of the operating element 4: (d ² x) from the temporal change of the position p of the operating element 4. / Dt ² , d ² y / dt ² , d ² z / dt ² ) can be detected by calculation. Since the operator 4 and the instrument panel 400 are relatively fixed, the position p of the operator 4, the speed v of the operator 4, and the acceleration a of the operator 4 are respectively the position of the instrument panel 400, the speed of the instrument panel 400, This corresponds to the acceleration of the instrument panel 400.

The processing unit 62 stores various parameters used for calculation processing described later. For example, the proportional coefficient (inertia coefficient) M with respect to the acceleration a in the above-described equation (1) is stored. Further, a reference value Do and Fa for calculating a proportionality coefficient (viscosity coefficient) D with respect to the speed v (refer to formula (2) described later) are stored. Further, a proportional coefficient (rigidity coefficient) K and the like with respect to the position p are stored. These calculation parameters are taught in advance by the operator using the operation panel 64, and can be adjusted as necessary.
The processing unit 62 of the control unit 60 detects the operating force f applied by the operator to the operating element 4, the position p of the operating element 4, the speed v of the operating element 4, etc., and stores the stored parameter values. Is used to sequentially calculate the force τ to be applied to the operation element 4 and teach each driver 14, 24, 34. Each driver 14, 24, 34 operates each actuator 12, 22, 32 such that each actuator 12, 22, 32 outputs the taught force τ. Hereinafter, the force output by the first actuator 12 is τx, the force output by the second actuator 22 is τy, and the force output by the third actuator 32 is τz. The work assisting device 2 operates so as to supplement the force applied by the operator to the operation element 4 and moves the instrument panel 400 together with the operation element 4. By setting the value of the inertia coefficient M to be smaller than the mass of the instrument panel 400, the operator can transport the instrument panel 400 with a force when transporting an object that is lighter than the instrument panel 400.

  Next, with reference to FIG. 3, the flow of operation of the work assisting device will be described. FIG. 3 is a flowchart showing a flow of processing executed by the processing unit 62. The processing unit 62 stores a program for executing the processing flow shown in FIG. In the process shown in FIG. 3, “position-based impedance control” is used. The processing unit 62 repeatedly executes the process shown in FIG. 3 for each operation cycle Δt. In the following processing, the proportionality coefficient (rigidity coefficient) K with respect to the position p is set to zero.

In step S2, the position of the operation element 4 is calculated based on the output signals of the position sensors 16, 26, and 36. Hereinafter, the position of the operator 4 at time t is described as p (t), and the xyz coordinates of the operator 4 at that time are described as (px (t), py (t), pz (t)).
In step S4, the speed v of the operator 4 is detected. Specifically, the speed v of the operation element 4 is detected from the change with time of the position p of the operation element 4. The temporal change in the position p of the operation element 4 is, for example, the position p (t) of the operation element 4 calculated in step S2 of the current operation cycle and the position p (t−Δt) of the operation element 4 calculated in the previous operation cycle. ) And the operation period Δt. Hereinafter, the speed of the operator 4 at time t is described as v (t), and the components in the x direction, the y direction, and the z direction are vx (t), vy (t), and vz (t).
In step S <b> 6, based on the output signal of the force sensor 6, the operation force applied to the operator 4 by the operator is detected. The processing unit 64 distinguishes and detects at least components in the x direction, the y direction, and the z direction, among the operating forces applied to the operator 4 by the operator. Hereinafter, the operating force applied to the operator 4 by the operator is described as f (t), and the components in the x direction, the y direction, and the z direction are expressed as fx (t), fy (t), fz (t ).

In step S8, a proportional coefficient (viscosity coefficient) D with respect to the speed in the equation (1) is determined. This proportionality coefficient D defines the viscous resistance force that is reproduced in the motion realized in the operation element 4. In this embodiment, the viscosity coefficient D is not constant and is changed according to the operating force f (t) detected in step S2. The processing unit 62 sets the viscosity coefficient D to a large value when the operating force f (t) is small, and sets the viscosity coefficient D to a small value when the operating force f (t) is large. If the viscosity coefficient at time t is D (t), the viscosity coefficient D (t) can be determined using, for example, the following equation.
D (t) = Do · {Fa / (Fa + | f (t) |)} (2)
The parameter Fa that adjusts the influence of the operating force f (t) and the reference value Do of the viscosity coefficient D in the above equation (2) are parameters that are appropriately set by the operator. Also, instead of the above equation (2),
D (t) = Do · {Fa ² / (Fa ² + f (t) ² )} (3)
D (t) = Do · exp (− | f (t) | / Fa) (4)
An arithmetic expression such as may be used. In any case, the viscosity coefficient D (t) can be corrected to a smaller value as the operating force f (t) is larger. In addition, the above equations (2), (3), and (4) are for monotonously decreasing the viscosity coefficient D (t) with respect to the increase in the operating force f (t), but the viscosity coefficient D (t) You may employ | adopt the system which changes this in steps.

In step S <b> 10, a resistance force Fr (t) virtually applied to the motion of the operation element 4 is calculated. The resistance force Fr (t) has a magnitude that is proportional to the speed of the operation element 4 and is a force that acts in a direction that hinders the movement of the operation element 4. That is, it corresponds to the viscosity term of the above-described equation (1). The resistance force Fr (t) can be calculated using, for example, the following equation using the viscosity coefficient D (t) calculated in step S8.
Fr (t) = − D (t) · v (t)
That is, the components Frx (t), Fry (t), and Frz (t) in the xyz direction are obtained by using the velocity components vx (t), vy (t), and vz (t) detected in step S4. It can be calculated by the formula.
Frx (t) = − D (t) · vx (t)
Fry (t) = − D (t) · vy (t)
Frz (t) = − D (t) · vz (t)
In addition, the negative sign attached to the viscosity coefficient D (t) in the above formula indicates that the resistance force Fr (t) and the speed v (t) are in opposite directions, and the resistance force Fr (t) Means that it acts in a direction that hinders the movement of the operation element 4.

In step S12, the target acceleration ad (t) of the operator 4 is calculated. This target acceleration ad (t) is an acceleration generated in the object when the operation force f (t) and the resistance force Fr (t) are applied to the object of mass M that is simulated by the operation element 4. Alternatively, the target acceleration ad (t) may be obtained by applying an operation force f to an object having a mass M simulated by the operation element 4 in an environment where a resistance force Fr (t) proportional to the speed acts. This is the acceleration that occurs on the object when added. The target acceleration ad (t) can be calculated using, for example, the following equation.
ad (t) = (f (t) + Fr (t)) / M
That is, each component adx (t), ady (t), and adz (t) in the xyz direction can be calculated by the following equation.
adx (t) = (fx (t) + Frx (t)) / M
ady (t) = (fy (t) + Fry (t)) / M
adz (t) = (fz (t) + Frz (t)) / M

In step S14, the target speed vd (t) of the operator 4 is calculated. The target speed vd (t) is a speed obtained by adding the speed change amount generated from the target acceleration ad (t) calculated in step S12 to the current speed v (t) of the operation element 4. The target speed vd (t) can be calculated using the following equation, for example.
vd (t) = v (t) + ad (t) · Δt
That is, each component vdx (t), vdy (t), vdz (t) in the xyz direction can be calculated by the following equation.
vdx (t) = vx (t) + adx (t) · Δt
vdy (t) = vy (t) + ady (t) · Δt
vdz (t) = vz (t) + adz (t) · Δt
When calculating the target speed vd (t), the target speed vd (t−Δt) calculated in the previous operation cycle is used instead of the current speed (detected value) v (t) of the operator 4. May be.

In step S16, the target position pd (t) of the operator 4 is calculated. The target position pd (t) is a position obtained by adding the displacement calculated from the target speed vd (t) and the operation period Δt to the current position p (t) of the operation element 4. The target position pd (t) can be calculated using the following equation, for example.
pd (t) = p (t) + vd (t) · Δt
That is, each component pdx (t), pdy (t), pdz (t) in the xyz direction can be calculated by the following equation.
pdx (t) = px (t) + vdx (t) · Δt
pdy (t) = py (t) + vdy (t) · Δt
pdz (t) = pz (t) + vdz (t) · Δt
When calculating the target position pd (t), the target position pd (t−Δt) calculated in the previous operation cycle is used instead of the current position (detected value) p (t) of the operator 4. May be.

In step S18, after the operation cycle Δt, the speed v (t + Δt) of the operating element 4 changes to the target speed vd (t) calculated in step S14, and the position p (t + Δt) of the operating element 4 is calculated in step S16. An operation command is executed to each of the drivers 14, 24, and 34 so as to change to the target position pd (t). At this time, the processing unit 62 uses so-called proportional differential (PD) control. That is, the force τ (t) output from each actuator 12, 22, 32 is adjusted according to the difference between the target position pd (t) and the actual position p (t) and the rate of change of the difference. The change rate of the difference is equal to the difference between the target speed vd (t) and the actual speed v (t). That is,
τ (t) = α · (pd (t) −p (t)) + β · (vd (t) −v (t))
It becomes. Here, α and β are predetermined control parameters, which can be adjusted as appropriate. The output of each actuator 12, 22, 32 can be expressed by the following equation.
τx (t) = α · (pdx (t) −px (t)) + β · (vdx (t) −vx (t))
τy (t) = α · (pdy (t) −py (t)) + β · (vdy (t) −vy (t))
τz (t) = α · (pdz (t) −pz (t)) + β · (vdz (t) −vz (t))
After completing the process of step S18, the process returns to step S2 again, and the above process is repeatedly executed every operation cycle Δt.

By the above processing, the motion of the object in the environment where the resistance force Fr (corresponding to the viscous resistance force) proportional to the speed v acts on the motion of the operation element 4 is realized. At this time, the proportional coefficient D multiplied by the speed v when calculating the resistance force Fr is set to a larger value as the operating force f is smaller.
FIG. 4 is a graph showing temporal changes in the operating force f and the speed v when carrying work using the work auxiliary device 2. Even in the positioning stage in the second half of the transfer operation, it can be confirmed that the operating force f is not reversed with respect to the speed direction, and a good operational feeling is realized. In the work assisting device 2, a good operational feeling is given to the operation element 4 without requiring discrimination of the work stage.

  In the work assistance device 2, the processing flow shown in FIG. 3 is executed mainly by an electronic computer included in the processing unit 62. However, a similar processing flow can be executed even with a simple analog circuit, and a processing unit that executes the processing flow can be configured with an analog circuit. For example, a voltage corresponding to the speed of the operator can be obtained by connecting a differentiation circuit to the position sensor. A voltage corresponding to various parameters can be output by a constant voltage generation circuit using a resistor or a capacitor. In the calculation in each step, a voltage obtained by adding / subtracting / dividing the voltage corresponding to each index can be obtained by various arithmetic circuits. By configuring the processing unit with an analog circuit, the electrical configuration of the operating device is simplified, and the technique of this embodiment can be implemented in more operating devices.

In this embodiment, an example of using “position-based impedance control” has been described. However, by using the technology of this embodiment, it is possible to realize a work assistance device using “torque-based impedance control”. It is.
When “torque-based impedance control” is used, the motion characteristic equation of the operation element 4 including the movable bodies 10, 20, 30, the instrument panel 400, and the like is previously taught to the processing unit 62 by the following equation, for example.
f + τ = Ms · a + Ds · v + Fs · sgn (v) (5)
The above formula describes the movement realized by the operation element 4 when a person applies the operation force f to the operation element 4 and the actuators 12, 22 and 32 output the force τ. The symbol s attached to each coefficient in the equation (5) indicates that each coefficient relates to the operation element 4 (including a moving mechanism and the like). Further, sgn (v) in the above equation (5) is a sign function relating to the speed v, and sgn (v) = v / | v |. The third term Fs · sgn (v) in the above formula indicates the frictional force generated by the movable mechanism or the like of the work auxiliary device 2.

On the other hand, the processing unit 62 calculates the motion to be realized by the operation element 4 based on the detected operation force f using the above-described equation (1) and the like.
f = M · a + D · v (6)
At this time, the proportional coefficient D multiplied by the speed v is corrected so as to be smaller as the detected operating force f is smaller. For this correction, for example, the above-described equations (2), (3), and (4) can be used.

Next, the force τ to be output by the actuators 12, 22, and 32 in order to realize the motion calculated by the equation (6) in the motion of the operation element 4 can be calculated from the equations (5) and (6).
τ = {Ds− (Ms / M) · D} · v + Fs · sgn (v) − {1− (Ms / M)} · f · (7)
The processing unit 62 determines the force τ (t) to be output by the actuators 12, 22, and 32 from the above equation (7) and the detected speed v (t) and operating force f (t) of the operating element 4. To do. The processing unit 62 commands the drivers 14, 24, and 34, and the actuators 12, 22, and 32 output the force τ (t), whereby the processing unit 62 calculates the motion of the operation element 4 (6) Movement is realized. When an operator transports the instrument panel 400, the operator transports the instrument panel 400 with a force when transporting an object (mass M) placed in an environment in which a resistance force proportional to the speed (proportional coefficient D) acts. Can do.

  Since the work auxiliary device 2 includes the position sensors 16, 26, and 36 that detect the position of the operation element 4, it is possible to detect the movement that the operation element 4 is actually performing. That is, the position p of the operation element 4, the speed v of the operation element 4, and the acceleration a of the operation element 4 can be detected based on the output signals of the position sensors 16, 26, and 36. In this case, if the detected speed v, acceleration a, etc. of the operating element 4 are substituted into the above equation (6), a resistance force proportional to the speed (proportional coefficient D) is applied to the motion currently being performed by the operating element 4. When realizing the motion of an object (mass M) placed in an environment, the force required to be applied to the object can be calculated. The force corresponds to f in equation (6). At this time, the proportional coefficient D multiplied by the speed v is corrected so as to be smaller as the detected operating force f is smaller. For this correction, for example, the above-described equations (2), (3), and (4) can be used. The acceleration a of the operation element 4 can be detected more accurately by using an acceleration sensor.

On the other hand, the force required to realize the movement of the operation element 4 by the movement of the operation element 4 can be calculated from the above equation (5). The force corresponds to f + τ in the equation (5).
The actuator 12, 22, 32 outputs the force τ obtained by subtracting f calculated by the equation (6) from f + τ calculated by the equation (5), so that the motion of the operation element 4 is proportional to the speed (proportional coefficient D The motion of the object (mass M) placed in the environment where the resisting force acts is realized. By preparing a program for executing the above processing and teaching the processing unit 62 of the work assisting device 2, the work assisting device 2 can execute the “torque-based impedance control” described above. At this time, for detecting the operation force, without using a force sensor or the like, the force τ actually output by the actuator at that time is subtracted from the detected movement of the operation element and f + τ calculated from the equation (5). May be detected.

In the work assistance device 2, since it is necessary to transport the instrument panel 400 that is a heavy object, the movement of the operation element 4 has a mass M that is lighter than the mass Ms of the operation element 4 including the movable bodies 10, 20, and 30. The movement of the object is reproduced. On the other hand, depending on the operating device on which the operator operates the operating element, the mass Ms of the operating element including the movable mechanism is an appropriate value, and the viscous resistance force and the frictional force actually acting on the operating element can be ignored. is there. In this case, Ds = 0 and Fs = 0 are set in the equation (5), and M = Ms is set in the equation (6). As a result, equation (7) becomes
τ = D · v (8)
It becomes. That is, in such an operating device, the force that the actuator should apply to the operating element can be obtained from the detected speed v of the operating element. The actuator outputs the force τ obtained from the equation (8), thereby realizing the motion of the object (mass M) in an environment where a resistance force proportional to the speed (proportional coefficient D) acts on the motion of the operating element. Is done. At this time, by setting the proportionality coefficient D to be larger as the detected operating force f is smaller, it is possible to give a better operational feeling to the operator.

Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.
In this embodiment, the position and speed of the operating element are detected by using a position sensor, but a speed sensor may be separately prepared for detecting the speed.
The mass imitating the operator may be set smaller than the mass including the operator and its moving mechanism. Thereby, the operation feeling of the operator that is too light can be improved.
When calculating the viscosity coefficient D based on the operating force, the formula (2), the formula (3), and the formula (4) are not limited, and other formulas may be used. By preparing various calculation formulas, it is possible to variously adjust the operational feeling given to the operation element.
When calculating the motion realized in the operation element, in addition to the resistance force Fr proportional to the speed, for example, a resistance force corresponding to a frictional force may be added. When a resistance force corresponding to the friction force is taken into account, a certain resistance force (negative force) may be added to the resistance force Fr calculated in step S10.
The actuator control method is not limited to the proportional differential (PD) control method, and other control methods may be adopted.

  The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

The figure which shows the external appearance of a conveyance work assistance apparatus. The block diagram which shows the structure of a conveyance work assistance apparatus. The flowchart which shows the flow of a process of a conveyance work assistance apparatus. The figure which shows the relationship between the operation force at the time of the conveyance work by a work auxiliary device, and conveyance speed. The figure which shows the conventional impedance characteristic.

Explanation of symbols

2 .. Work auxiliary device 4 .. Operation element 6 .. Force sensor 8 a, 8 b... Fixed rails 10, 20, 30... 1st, 2nd, 3rd movable bodies 12, 22, 32. , Second, third actuators 14, 24, 34,..., First, second, third drivers 16, 26, 36,..., First, second, third position sensors 60,. 400 ... Instrument panel

Claims (6)

An operator operated by a person,
An operation force detecting means for detecting an operation force applied by a person to the operation element;
A motion adjusting means for realizing the motion generated in the object when the operating force detected by the operating force detecting means is applied to an object in an environment where a resistance force proportional to the speed is applied to the motion of the operator. Prepared,
The operation device is characterized in that the smaller the operation force applied by the person to the operation element, the larger the proportional coefficient used when determining the resistance force by multiplying the speed. The movement adjusting means includes
A motion calculating means for calculating the motion generated in the object when the operating force detected by the operating force detecting means is applied to an object in an environment where a resistance force proportional to the speed acts;
An actuator that realizes the motion calculated by the motion calculation means to the motion of the operator,
2. The operation according to claim 1, wherein the motion calculation unit sets a larger proportional coefficient to be used when calculating the resistance force by multiplying the speed as the operation force detected by the operation force detection unit is smaller. apparatus. A speed detecting means for detecting the speed of the operation element is added.
The motion calculation means includes
Storage means for storing a reference value of the proportionality coefficient;
Coefficient correction means for correcting the reference value of the proportionality coefficient stored in the storage means to be larger as the operation force detected by the operation force detection means is smaller;
A resistance force calculating means for calculating the resistance force by multiplying the proportionality coefficient corrected by the coefficient correcting means by the speed of the operator detected by the speed detecting means;
Considering the speed change caused by the acceleration resulting from the resultant force of the operation force detected by the operation force detection means and the resistance force calculated by the resistance force calculation means to the speed of the operation element detected by the speed detection means, 3. The operating device according to claim 2, further comprising a target speed calculating means for calculating the target speed. Motion detection means for detecting the motion of the operator is added,
The movement adjusting means includes
A force calculating means for calculating a force required to be applied to an object when the motion detected by the motion detecting means is realized as a motion of an object placed in an environment where a resistance force proportional to the speed acts;
An actuator that applies to the operator a force obtained by subtracting the force calculated by the force calculating means from the force required to realize the movement detected by the movement detecting means in the movement of the operator,
2. The operation according to claim 1, wherein the force calculation unit sets a larger proportional coefficient to be used when calculating the resistance force by multiplying the speed as the operation force detected by the operation force detection unit is smaller. apparatus. It is a method of adjusting the operation of the operator operated by a person with an actuator,
An operation force detection step for detecting an operation force applied by a person to the operation element;
When the operation force detected in the operation force detection process is applied to an object placed in an environment where a resistance force proportional to the speed acts, the movement that occurs in the object is realized by controlling the actuator to the movement of the operator. A movement adjustment process,
In the movement adjustment step, the smaller the operation force detected in the operation force detection step is, the larger the proportional coefficient used when determining the resistance force by multiplying the speed is set. Method. This is a program for adjusting the operation of a manipulator operated by a person with an actuator.
A process of inputting an operation force applied by a person to an operation element;
When the input operating force is applied to an object placed in an environment where a resistance force proportional to the speed acts, the motion adjustment processing that realizes the motion that occurs in the object to the motion of the operator by controlling the actuator A program to be executed,
In the motion adjustment process, the smaller the input operation force is, the larger the proportional coefficient used when determining the resistance force by multiplying the speed is set.

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