JP4404789B2 - Operation device, operation adjustment method for operation device, and program therefor - Google Patents

Description

  The present invention relates to a technique for adjusting the operation of an operator operated by a person using an actuator or the like. In particular, the present invention relates to a technique for calculating a target motion realized by an operator from an operation force applied by a person to the operator and adjusting the motion of the operator by an actuator or the like.

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.

Technology that utilizes impedance control has been developed. The work assisting device 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 as a result. 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

If the method is to calculate the target movement of the operating element that satisfies the relationship of the expression (1) shown above from the operating force applied by the person to the operating element, and adjust the movement of the operating element with an actuator, etc. The operator responds sensitively to slight camera shake, which may amplify human camera shake. When a fine operation is performed, the operational feeling is worsened and the operability is lowered.
Therefore, in the technique of Patent Document 1, in the stage of determining the position by finely moving the object, the operation reaction force is increased by increasing the proportional coefficient D with respect to the speed. However, this technology is based on the fact that heavy goods transportation work can be roughly divided into a plurality of work stages assumed in advance, and is effective when a series of operations are relatively fixed, such as heavy goods transportation work. However, there is a lack of versatility when applied to a controller for various other purposes.
The present invention solves the above problems. The present invention provides a highly versatile technique for improving the operability of the operator.

The present inventor has studied various reasons why good operability cannot be obtained even if the movement of the operation element is controlled so as to satisfy the relationship of the above-described expression (1).
As a result, the frictional force existing in the natural world is not taken into consideration in the expression (1), and an operation feeling when operating in an unnatural environment where there is no frictional force is given to the operator. Recognized that there is. For example, when an object is transported and positioned at a predetermined position in a plane, a person positions the object while using the frictional force in consideration of the frictional force acting on the object from the plane. In the method of controlling the movement of the operation element so as to satisfy the relationship of the expression (1), the friction force existing in the natural world is not taken into account and the natural operation cannot be reproduced.

It is difficult to reproduce the frictional force in the movement of the operation element by calculating the target movement of the operation element from a human operation force and adjusting the movement of the operation element by an actuator or the like. Conventionally, research has been conducted in the direction of eliminating the frictional force, and there is very little research for reproducing the frictional force.
The present inventors recognize that it is important to use frictional force in order to obtain a natural and good operability, and tackle the problem of reproducing frictional force that is difficult to handle. It came to be completed.

  The present invention can be embodied in an operating device that adjusts the operation of an operator following a human operation. This operating device is detected by an operator operated by a person, an operating force detecting means for detecting an operating force applied by the person to the operating element, a speed detecting means for detecting the speed of the operating element, and a speed detecting means. First speed calculating means for calculating a first speed by adding an acceleration caused by the operating force detected by the operating force detecting means and a speed change amount calculated from unit time to the speed of the operating element; An opposite force setting means for setting an opposite force opposite to the first speed calculated by the speed calculation means, and an acceleration caused by the opposite force set by the opposite force setting means to the first speed calculated by the first speed calculation means And a speed for adjusting the speed of the operator to the second speed calculated by the second speed calculating means by adding the speed change amount calculated from the unit time and the second speed calculating means. Adjusting means. The counter force setting means sets the force calculated from the acceleration that reduces the first speed to zero per unit time as the counter force when the calculated first speed is equal to or lower than a predetermined speed.

In this device, the acceleration that should be generated due to the operating force is calculated from the operating force applied by the person to the operating element. At this stage, the frictional force is not considered. By solving the acceleration a from the above-described equation (1), the acceleration that should be generated due to the operating force f can be calculated. For example, if it is not necessary to consider the viscous force or the spring force, the acceleration a can be obtained from the equation [M · a = f]. If a viscous force or a spring force is taken into account, the acceleration a can be solved from the above equation (1) together with the current position p and current speed v of the operator.
When the acceleration is known, the speed change amount after unit time can be calculated. Then, the speed after unit time can be calculated by adding the speed change amount calculated from the acceleration to the detected current speed. This is the first speed calculated by this apparatus. The first speed is a speed when the frictional force is not taken into account, and corresponds to the speed of the operator calculated by the conventional impedance control. The unit time corresponds to, for example, a calculation cycle of a calculation device or the like.

In this device, an opposite force corresponding to the friction force is set based on the first speed. The opposite force is a force opposite to the first speed. The magnitude of the counter force can be adjusted in accordance with the friction force reproduced by the operation element. It may be a fixed value or may be changed according to the first speed. However, if the opposite force when the calculated first speed is small is set large, the second speed calculated later is reversed with respect to the first speed. Since the frictional force has no effect of moving the object in the opposite direction, the second speed must be calculated as zero in such a case. Therefore, in this apparatus, when the first speed is equal to or lower than the predetermined speed, the force calculated from the acceleration that reduces the first speed to zero in unit time is set to the opposite force. That is, when the first speed is equal to or lower than the predetermined speed, the opposite force is set so that the second speed calculated later becomes zero.
When the opposite force is set, the acceleration caused by the opposite force can be calculated. Here too, when it is not necessary to consider the viscous force or the spring force, the acceleration can be obtained from the equation [M · a = opposing force]. When the acceleration caused by the counter force is found, the amount of speed change after a unit time can be calculated. Then, the speed after unit time can be calculated by adding the speed change amount caused by the opposite force to the first speed. This is the second speed calculated by the present apparatus, which is a speed that takes into account the influence of frictional force.
Finally, the speed of the operator is adjusted to the second speed calculated by the second speed calculating means by the speed adjusting means. Frictional force is reproduced in the movement of the operator.

  According to this apparatus, the frictional force can be correctly reproduced in the movement of the operation element. The operation element is given a natural feeling of operation, and the operability of the operation element can be improved. It is not necessary to determine the work stage, and it can be employed in various operation devices such as mechanical devices.

In the above operating device, it is preferable to add a storage means for storing the frictional force reproduced by the movement of the operating element as a function of speed. In this case, the predetermined speed that the counter force setting means compares with the first speed is equal to the speed change amount calculated from the acceleration caused by the friction force stored in the storage means and the unit time with respect to zero speed. It is preferable.
The frictional force stored in the storage unit with respect to zero speed corresponds to the maximum static frictional force reproduced in the movement of the operation element. By setting the speed variation calculated from the acceleration caused by the maximum static friction force and the unit time to the predetermined speed, the static friction force can be correctly reproduced in the movement of the operator.

The counter force setting means preferably sets the counter force based on the frictional force stored in the storage means when the calculated first speed exceeds a predetermined speed.
For example, when the storage means stores a constant friction force for all speeds, the friction force stored by the storage means for the first speed can be set to the opposite force.
On the other hand, in the case where the storage means stores the frictional force changing with respect to the speed, if the frictional force stored in the storage means for the first speed is set to the opposite force, the first Before and after the speed reaches the predetermined speed, the set counter force changes discontinuously.
Therefore, for example, when the storage means stores a friction force that changes with speed, the friction force stored in the storage means is opposite to the speed obtained by subtracting the predetermined speed from the first speed. It is preferable to set the force.
Alternatively, an opposite force that satisfies the relationship in which the opposite force to be set and the frictional force stored in the storage unit with respect to the second speed calculated from the opposite force may be set as the opposite force. Since the counter force and the second speed depend on each other, the counter force to be set can be calculated by executing an analytical calculation, for example.

The present invention can also be embodied in a method for adjusting the operation of an operator operated by a person. In this method, an operation force detection process for detecting an operation force applied by a person to the operation element, a speed detection process for detecting the speed of the operation element, and an operation force detection based on the speed of the operation element detected in the speed detection process. The first speed calculated in the first speed calculating step and the first speed calculating step in which the first speed is calculated by taking into account the acceleration caused by the operating force detected in the step and the speed change amount calculated from the unit time. The speed change calculated from the acceleration and unit time caused by the counterforce set in the counterforce setting step to the counterspeed setting step for setting the counterforce in the opposite direction to the first speed calculated in the first speed calculation step A second speed calculating step for calculating the second speed by adding the amount, and a step for adjusting the speed of the operator to the second speed calculated in the second speed calculating step are provided. In the counter force setting step, when the calculated first speed is equal to or less than a predetermined speed, the force calculated from the acceleration that reduces the first speed to zero in unit time is set to the counter force. .
According to this method, it is possible to reproduce the motion of an object in which a frictional force acts on the motion of the operation element. The operation element is given a natural feeling of operation, and the operability of the operation element can be improved. It is not necessary to determine the work stage, and it can be employed in various operation devices such as mechanical devices.

The present invention can also be embodied in a program that is executed by an electronic computer provided in an operating device that adjusts the operation of an operator operated by a person by means of speed adjusting means. This program is based on the process of inputting the operation force applied by the person to the operation element, the process of inputting the speed of the operation element, and the acceleration and unit time caused by the input operation force to the input operation element speed. A first speed calculation process for calculating the first speed by taking into account the calculated speed change amount; and an opposite force setting process for setting an opposite force opposite to the first speed calculated in the first speed calculation process; The second speed is calculated by adding the speed change calculated from the acceleration caused by the counter force set in the counter force setting process and the unit time to the first speed calculated in the first speed calculation process. This is a program for executing a two-speed calculation process and a process for controlling the speed adjusting means to adjust the speed of the operator to the second speed calculated by the second speed calculation process. In the counter force setting process, when the calculated first speed is equal to or lower than a predetermined speed, the force calculated from the acceleration that reduces the first speed to zero in unit time is set to the counter force.
By using this program, it is possible to reproduce the motion of an object in which a frictional force acts on the motion of the operator. The operation element is given a natural feeling of operation, and the operability of the operation element can be improved. It is not necessary to determine the work stage, and it can be employed in various operation devices such as mechanical devices.

  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. The first actuator, the second actuator, and the third actuator can adjust the position, speed, and acceleration of the operation element.
(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, a storage unit 66 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 calculation parameters. The operation panel 64 displays information from the processing unit 62 to the operator.
The storage unit 66 stores a program used when the processing unit 62 executes a process described later, an operation parameter used when the processing unit 62 executes a process described later, and the like. The storage unit 66 stores, for example, the proportionality coefficient (inertia coefficient) M for the acceleration a, the proportionality coefficient (viscosity coefficient) D for the velocity v, the proportionality coefficient (rigidity coefficient) K for the position p, and the like. is doing. Further, a frictional force function φ describing the relationship between the magnitude of the frictional force F reproduced in the movement of the operator 4 and the speed v is stored. These calculation parameters and the like are previously taught by the operator using the operation panel 64 and can be adjusted as necessary. Calculation parameters and the like input from the operation panel 64 by the operator are stored in the storage unit 66 via the processing unit 62.

Here, the frictional force function φ describing the relationship between the frictional force F and the speed v will be described. FIG. 3 shows four examples of the friction force function φ. Note that the frictional force function φ shown in FIG. 3 describes only the relationship between the magnitude | F | of the frictional force F and the magnitude | v | In order to reproduce the frictional force having no anisotropy in the movement of the operation element 4, the magnitude F of the frictional force F is sufficient. When reproducing a frictional force having anisotropy in the motion of the operation element 4, it is preferable to prepare a frictional force function φ describing the frictional force F with respect to a speed v having a direction.
The frictional force function φ shown in FIG. 3A is φ (| v |) = Fc. This frictional force function φ indicates that the magnitude | F | of the frictional force F is a constant Fc with respect to the magnitude | v | of an arbitrary speed v. When reproducing the friction force (so-called Coulomb friction force) in which the dynamic friction force and the maximum static friction force are equal to the motion of the operation element 4, it is preferable to use the friction force function φ shown in FIG.
The frictional force function φ shown in FIG. 3B is φ (| v |) = Fs when | v | = 0, and φ (| v |) = Fc when | v |> 0. It is shown that. This frictional force function φ indicates that the maximum static frictional force is a constant Fs and the dynamic frictional force is a constant Fc. When reproducing the frictional force different from the dynamic frictional force and the maximum static frictional force in the movement of the operation element 4, it is preferable to use the frictional force function φ shown in FIG.

The frictional force function φ shown in FIG.
φ (| v |) = Fc + D · | v | (2)
It is. This frictional force function φ indicates that the magnitude | F | of the counter force F increases in proportion to the magnitude | v | of the velocity v. When the frictional force that increases in proportion to the speed is reproduced in the movement of the operator 4, the frictional force function φ shown in FIG. Such a frictional force corresponds to a frictional force generated when, for example, lubricating oil is present on the friction surface.
The frictional force function φ shown in FIG. 3D is φ (| v |) = Fc− (Fs + Fc) · exp (− (| v | / Vs) δ). This frictional force function φ indicates that the magnitude | F | of the opposite force F decreases in proportion to the magnitude | v | of the velocity v. When the frictional force that decreases in proportion to the speed is reproduced in the movement of the operation element 4, it is preferable to use the frictional force function φ shown in FIG. Such a frictional force corresponds to a frictional force generated when, for example, lubricating oil is present on the friction surface and the lubricating oil film becomes thick due to an increase in speed. Note that Vs and δ in the above formula are predetermined parameters and can be obtained by experiments or the like.

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 of the control unit 60 detects the operation force f applied by the operator to the operation element 4, the position p of the operation element 4, the speed v of the operation element 4, and the like, and stores the stored operation parameters. The force τ to be applied to the operation element 4 is sequentially calculated and taught to the drivers 14, 24 and 34. Each driver 14, 24, 34 adjusts the operation of each actuator 12, 22, 32 based on 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. 4, the flow of operation of the work assisting device 2 will be described. FIG. 4 is a flowchart showing the flow of processing executed by the processing unit 62. The processing unit 62 executes the processing program shown in FIG. 4 by executing the processing program stored in the storage unit 66. The processing unit 62 repeatedly executes the process shown in FIG. 4 every unit time Δt. In the process described below, the proportionality coefficient (viscosity coefficient) D with respect to the velocity v and the proportionality coefficient (rigidity coefficient) K with respect to the position p are set to zero, and the frictional force function φ illustrated in FIG. Shall be used.

In step S2, the position p (t) of the operation element 4 is detected 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 (t) of the operating element 4 is detected from the change with time of the position p of the operating 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 unit time 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 first acceleration ac (t) is calculated. The first acceleration ac (t) is an acceleration generated in the object when the operating force f (t) detected in step S6 is applied to the object of mass M that is simulated by the operating element 4. The first acceleration ac (t) can be calculated from, for example, the following expression based on the above expression (1).
ac (t) = (f (t) -D.v (t) -K. (p-po)) / M
That is, each component acx (t), acy (t), and acz (t) in the xyz direction can be calculated by the following equation.
acx (t) = (fx (t) -D.vx (t) -K. (px-po)) / M
acy (t) = (fy (t) −D · vy (t) −K · (py−po)) / M
acz (t) = (fz (t) -D.vz (t) -K. (pz-po)) / M
Here, since the proportionality coefficient (viscosity coefficient) D with respect to the velocity v and the proportionality coefficient (rigidity coefficient) K with respect to the position p are set to zero, the viscosity term D · v (t) and the stiffness term K · ( p-po) is zero.

In step S10, the speed v (t) of the operating element 4 detected in step S4 is added to the speed change amount after the unit time Δt generated from the first acceleration ac (t) calculated in step S8. The speed vc (t) is calculated. The first speed vc (t) can be calculated from the following equation, for example.
vc (t) = v (t) + ac (t) · Δt
That is, each component vcx (t), vcy (t), and vcz (t) in the xyz direction can be calculated by the following equation.
vcx (t) = vx (t) + acx (t) · Δt
vcy (t) = vy (t) + acy (t) · Δt
vcz (t) = vz (t) + acz (t) · Δt
The first speed vc (t) is obtained when the operating force f (t) detected in step S6 is applied to an object of mass M moving at the speed v (t) after a unit time Δt. This is the speed that is achieved. The first speed vc (t) is a speed when a frictional force does not act on the object.
The first acceleration ac (t) calculated in step S8 and the first speed vc (t) calculated in step S10 can be calculated using conventional impedance control. The calculation of the first acceleration ac (t) and the first speed vc (t) is based on the above equation (1), and the specific calculation method is not limited to the above method.

The counter force F (t) is set by the processing of subsequent steps S12, S14, and S30. The direction of the counter force F (t) is opposite to the first speed vc (t) calculated in step S10. The force corresponding to the frictional force is reproduced in the movement of the operation element 4 by the opposite force F (t) set here.
First, in step S12, it is determined whether or not the magnitude | vc (t) | of the first speed vc (t) is equal to or less than the reference speed ε. The reference speed ε used for this determination is a speed change amount calculated from the acceleration caused by the friction force F = φ (0) described by the friction force function φ with respect to the speed zero and the unit time Δt. That is,
ε = (φ (0) · Δt) / M
It becomes. Here, since φ (0) = Fc, ε = (Fc · Δt) / M. If this determination is yes, the process proceeds to step S14, and if this determination is no, the process proceeds to step S30.

In step S14 and step S30, the method of setting the opposite force F (t) is different. That is, the method for setting the counter force F (t) is changed depending on whether the magnitude | vc (t) | of the first speed vc (t) is equal to or less than the reference speed ε.
In step S14, the counter force F (t) to be set is determined by the following equation. At this time, the frictional force function φ is not used.
F (t) = − M · vc (t) / Δt
That is, each component Fx (t), Fy (t), and Fz (t) in the xyz direction can be calculated by the following equation.
Fx (t) = − M · vcx (t) / Δt
Fy (t) = − M · vcy (t) / Δt
Fz (t) = − M · vcz (t) / Δt
The minus sign in the above equation indicates that the opposite force F (t) and the first speed vc (t) are in opposite directions. The counter force F (t) determined by the above equation is the force (−M · vc (t) calculated from the acceleration (−vc (t) / Δt) that reduces the first speed vc (t) to zero in unit time Δt. ) / Δt). In other words, when the first speed vc (t) is equal to or less than the reference speed ε = (Fc · Δt) / M, the counter force F () is set so that the second speed calculated in the subsequent step S16 becomes zero. t) is set.

On the other hand, in step S30, the opposite force F (t) is set based on the friction force function φ. Here, the counter force F (t) to be set is determined by substituting the first speed vc (t) for the friction force function φ.
F (t) = − sgn (vc (t)) · φ (| vc (t) |)
= −sgn (vc (t)) · Fc
In the above equation, sgn (vc (t)) is a sign function. -Sgn (vc (t)) indicates that the opposite force F (t) and the first speed vc (t) are in opposite directions. In FIG. 4, a minus sign is substituted for simplification.
That is, each component Fx (t), Fy (t), and Fz (t) in the xyz direction can be calculated by the following equation.
Fx (t) = − Fc · vcx (t) / | vc (t) |
Fy (t) = − Fc · vcy (t) / | vc (t) |
Fz (t) = − Fc · vcz (t) / | vc (t) |
In the above processing, the processing unit 62 calculates the first speed vc (t) based on the operating force f (t) and the current speed v (t) of the operating element 4. Next, the counter force F (t) is set based on the first speed vc (t). That is, the processing unit 62 sets the opposite force F (t) based on both the operating force f (t) and the current speed v (t) of the operating element 4.

In step S16, the second acceleration ad (t) is calculated. The second acceleration ad (t) is an acceleration generated in the object when the opposite force F (t) set in steps S14 and S30 is applied to the object of mass M. The second acceleration ad (t) can be calculated from the following equation, for example.
ad (t) = F (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) / M
ady (t) = Fy (t) / M
adz (t) = Fz (t) / M

In step S18, the second speed vd is calculated by adding the speed change amount after unit time Δt generated from the second acceleration ad (t) calculated in step S16 to the first speed vc (t) calculated in step S10. (T) is calculated. The second speed vd (t) is a speed realized after a unit time Δt of the object when the frictional force F (t) is applied to the object of mass M moving at the first speed vc (t). It is. The second speed vd (t) can be calculated using the following equation, for example.
vd (t) = vc (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) = vcx (t) + adx (t) · Δt
vdy (t) = vcy (t) + ady (t) · Δt
vdz (t) = vcz (t) + adz (t) · Δt
When the counter force F (t) is set by the process in step S14, the second speed vd (t) calculated in step S18 is zero.

In step S20, the target position pd (t) of the operator 4 is calculated. The target position pd (t) is a position in which the displacement calculated from the second speed vd (t) and the unit time Δt is added to the current position p (t) of the operator 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

In step S <b> 22, the processing unit 62 executes an operation command to each driver 14, 24, 34. The processing unit 62 changes the speed v (t + Δt) of the operator 4 to the second speed vd (t) calculated in step S18, and the position p (t + Δt) of the operator 4 calculated in step S20. An operation command is given to each of the drivers 14, 24, and 34 so as to change to (t). At this time, the processing unit 62 uses so-called proportional differential (PD) control. That is, the force τ (t) output by each actuator 12, 22, 32 is adjusted according to the deviation between the target position pd (t) and the actual position p (t) and the rate of change of the deviation. The change rate of the position deviation is equal to the deviation 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 and can be appropriately adjusted. 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 S22, the process returns to step S2 again, and the above process is repeatedly executed every unit time Δt.
In step S8, the first acceleration ac (t) is calculated in consideration of the viscosity term D · v (t). However, the viscosity term D · v (t) is expressed by the above equation (2). In addition, it can be included in the frictional force φ (| v |).
Further, when the first speed vc (t) is calculated in step S10, the target speed vd (t−) calculated in the previous operation cycle is used instead of the current speed (detected value) v (t) of the operation element 4. Δt) may be used. Furthermore, when calculating the target position pd (t) in step S20, 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 operation element 4. ) May be used.
Through the above processing, the operation of the operator 4 is adjusted by the actuators 12, 22, and 32 following the operation performed by the operator on the operator 4.

With reference to FIG. 5, FIG. 6, the movement implement | achieved by the operation element 4 when an operator operates the operation element 4 is demonstrated. In each graph shown in FIGS. 5 and 6, the horizontal axis indicates the speed of the operation element 4, and the vertical axis indicates the counter force F. In each graph, the current speed v (t) of the operator 4, the first speed vc (t) taking into account the operating force f, and the counter force F (t (t) set based on the first speed vc (t) ) And the second speed vd (t) in consideration of the counter force F (t).
FIG. 5A shows a case where the operator applies an operating force f greater than Fc to the stationary operation element 4 (current speed v (t) = 0). This corresponds to, for example, when the operator operates the operator 4 to start conveying the instrument panel 400. In this case, the first speed vc (t) calculated in step S10 is larger than the determination reference speed ε = Fc · Δt / M in step S12. The first speed vc (t), the counter force F (t), and the second speed vd (t) are in the relationship shown in FIG. 5A, and the operator 4 that has been stationary starts to move.
FIG. 5B shows a case where the operator applies an operation force f equal to or less than Fc to the stationary operation element 4 (current speed v (t) = 0). This corresponds to, for example, when a hand shake occurs when the operator holds the operation element 4 and stops the instrument panel 400. In this case, the first speed vc (t) calculated in step S10 is equal to or less than the determination reference speed ε = Fc · Δt / M in step S12. The first speed vc (t), the counter force F (t), and the second speed vd (t) have the relationship shown in FIG. 5B, and the operation element 4 continues to be stationary.
When the operation element 4 is stationary, the operation element 4 starts to move when the operation force f exceeds Fc, and the operation element 4 continues to be stationary when the operation force f is equal to or less than Fc. A static friction force whose maximum static friction force is Fc is reproduced in the movement of the operation element 4. The camera shake of the worker is not amplified.

FIGS. 6A and 6B show a case where the operator applies an operating force f to the moving operator 4 in the direction in which the operator 4 is braked. FIG. 6A shows a case where the applied operating force f is small, and the first speed vc (t) calculated in step S10 is higher than the determination reference speed ε = Fc · Δt / M in step S12. The case where it becomes large is shown. In this case, the first speed vc (t), the counter force F (t), and the second speed vd (t) have the relationship shown in FIG. 6A, and the operation element 4 continues to move.
FIG. 6B shows a case where the applied operating force f is large, and the first speed vc (t) calculated in step S10 is equal to or less than the determination reference speed ε = Fc · Δt / M in step S12. Shows the case. In this case, the first speed vc (t), the counter force F (t), and the second speed vd (t) are in the relationship shown in FIG. 6B, and the moving operation element 4 stops. . As shown in FIG. 6B, since the counter force F (t) is limited as compared with Fc, the second speed vd (t) may be reversed with respect to the first speed vc (t). Absent.
When the operating element 4 is moving, the operating element 4 may continue to move or the operating element 4 may be stationary depending on the magnitude of the operating force f. When the operation element 4 continues to move, the dynamic friction force is reproduced in the movement of the operation element 4. When the operation element 4 is stationary, the static friction force is reproduced, and the operation element 4 is stably stationary.
As described above, the static friction force and the dynamic friction force are correctly reproduced in the movement of the operation element 4. The operation element 4 is given a natural feeling of operation, and the operator can easily perform the positioning operation of the instrument panel 400.

Although the case where the frictional force function φ shown in FIG. 3A is used has been described above, the same applies to the case where another frictional force function φ shown in FIG. 3 is used. The frictional force described by the frictional force function φ can be reproduced in the movement of the operator 4.
However, when using a friction force function φ that increases or decreases in accordance with the speed, such as the friction force function φ in FIGS. 3C and 3D, it is preferable to add the processing described below.

As shown in FIG. 7A, for example, in the case of using the frictional force function φ shown in FIG. 3D, when the first speed vc is around the determination reference speed ε = (Fc · Δt) / M. , The set counter force F becomes discontinuous. When the opposite force F is set discontinuously with respect to the first speed, the calculated second speed vd is also discontinuous. As a result, the speed of the operation element 4 changes discontinuously, and an unnatural motion is reproduced in the operation element 4. Therefore, when the first speed vc is larger than the determination reference speed ε = (Fc · Δt) / M and the opposite force F is set from the first speed vc and the frictional force function φ (step S30 in FIG. 4), The frictional force function φ should be corrected for use. As shown in FIG. 7B, the opposite force F changes continuously with respect to the first speed by translating the frictional force function φ by the movement amount Δv in the speed axis direction. This corrected friction force function φ will be referred to as a corrected friction force function φ ^* . The corrected frictional force function φ ^* can be expressed by the following equation.
φ ^* (vc) = φ (vc−Δv)
For example, a determination reference speed ε = (Fc · Δt) / M can be set for the movement amount Δv. In this case, for example, a corrected friction force function φ ^* is prepared from the friction force function φ, and the opposite force F can be set from the first speed vc and the corrected friction force function φ ^* . Alternatively, the counter force F may be set from the speed obtained by subtracting the determination reference speed ε = (Fc · Δt) / M from the first speed vc and the frictional force function φ.

Alternatively, the modified frictional force function φ ^*
φ ^* (vc) = F s. t. F = φ (vc + F · Δt / M)
May be defined. In the above equation, the counter force F determined from the first speed vc and the corrected friction force function φ ^* is equal to the counter force F determined from the second speed (vc + F · Δt / M) calculated as a result and the friction force function φ. It is shown that. That is, the opposite force F is set from the second speed vd and the frictional force function φ. In this case, the counter force F to be set can be obtained by executing analytical calculation on the above equation.
By using the modified frictional force function φ ^* exemplified above, it becomes possible to set the counter force F that continuously changes with respect to the first speed, and to suppress the operation element 4 from exhibiting unnatural behavior. can do. It is possible to use the corrected friction force function φ ^* even when the friction force F does not change according to the speed, for example, as in the friction force function φ shown in FIG.

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.
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 work assistance apparatus. The block diagram which shows the structure of a conveyance work assistance apparatus. The figure which illustrates a frictional force function. The flowchart which shows the flow of the process which a process part performs. The figure explaining the exercise | movement implement | achieved by the operator which is still. The figure explaining the exercise | movement implement | achieved by the operation element which is moving. The figure explaining a correction frictional force function.

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 (7)

An operator operated by a person,
An operation force detecting means for detecting an operation force applied by a person to the operation element;
Speed detecting means for detecting the speed of the operator;
The first speed for calculating the first speed by adding the speed change amount calculated from the acceleration caused by the operating force detected by the operating force detecting means and the unit time to the speed of the operating element detected by the speed detecting means. A calculation means;
An opposite force setting means for setting an opposite force opposite to the first speed calculated by the first speed calculating means;
A second speed for calculating the second speed by adding the speed change calculated from the acceleration caused by the counter force set by the counter force setting means and the unit time to the first speed calculated by the first speed calculation means. Speed calculation means;
Speed adjusting means for adjusting the speed of the operator to the second speed calculated by the second speed calculating means;
The counter force setting means sets the force calculated from the acceleration that reduces the first speed to zero per unit time as the counter force when the calculated first speed is equal to or less than a predetermined speed. . A storage means for storing the frictional force reproduced in the movement of the operation element as a function of speed is added.
The predetermined speed that the counter force setting means compares with the first speed is equal to an acceleration caused by the frictional force stored in the storage means with respect to zero speed and a speed change amount calculated from unit time. The operating device according to claim 1, characterized in that:   The said counter force setting means sets the friction force which the memory | storage means has memorize | stored with respect to 1st speed to an opposite force, when the said 1st speed exceeds the said predetermined speed. Operating device.   When the first speed exceeds the predetermined speed, the counter force setting means sets the frictional force stored in the storage means for the speed obtained by subtracting the predetermined speed from the first speed as the counter force. The operating device according to claim 2.   The counter force setting means has a relationship in which when the first speed exceeds the predetermined speed, the friction force stored in the storage means is equal to the counter force and the second speed calculated from the counter force. 3. The operating device according to claim 2, wherein the opposite force to be satisfied is set to the opposite force. It is a method of adjusting the operation of the operator operated by a person,
An operation force detection step for detecting an operation force applied by a person to the operation element;
A speed detection step for detecting the speed of the operator;
A first speed for calculating the first speed by adding the speed change amount calculated from the acceleration caused by the operation force detected in the operation force detection process and the unit time to the speed of the operation element detected in the speed detection process. A calculation process;
An opposite force setting step of setting an opposite force opposite to the first velocity calculated in the first velocity calculation step;
The second speed is calculated by adding the speed change amount calculated from the acceleration caused by the counter force set in the counter force setting step and the unit time to the first speed calculated in the first speed calculation step. Speed calculation step;
Adjusting the speed of the operator to the second speed calculated in the second speed calculation step,
In the counter force setting step, when the calculated first speed is equal to or lower than a predetermined speed, the force calculated from the acceleration that reduces the first speed to zero in unit time is set as the counter force. Child movement adjustment method. This is a program for adjusting the operation of a manipulator operated by a person by means of speed adjusting means.
A process of inputting an operation force applied by a person to an operation element;
Processing to input the speed of the control;
A first speed calculation process for calculating a first speed by adding an acceleration caused by the input operation force and a speed change amount calculated from unit time to the speed of the input operator;
An opposite force setting process for setting an opposite force opposite to the first speed calculated in the first speed calculation process;
The second speed is calculated by adding the speed change calculated from the acceleration caused by the counter force set in the counter force setting process and the unit time to the first speed calculated in the first speed calculation process. Speed calculation processing,
A program for controlling the speed adjusting means to execute the process of adjusting the speed of the operator to the second speed calculated by the second speed calculating process,
In the counter force setting process, when the calculated first speed is equal to or lower than a predetermined speed, a force calculated from an acceleration that reduces the first speed to zero per unit time is set as the counter force. .

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