Load control device

Abstract

To reduce load calculation for a control target subjected to locus constraint and ensure the degree of freedom of load design.SOLUTION: A locus energy calculator 2 of a load control device 1 calculates locus energy from a response position of a control target 10. An energy controller 3 outputs a first acceleration reference value for controlling the locus energy calculated from position responses of respective actuators according to a command value. A load controller 4 outputs a second acceleration reference value for controlling a load to be applied along the locus on the basis of the command value. An acceleration reference value calculation unit 5 reflects a unit vector in a normal direction of an equal energy line on the first acceleration reference value, reflects a unit vector in a tangential direction of the equal energy line on the second acceleration reference value, and adds the values together to calculate acceleration reference values of the respective actuators. An acceleration control unit 6 calculates torque command values of the respective actuators from the acceleration reference values of the respective actuators.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a device for controlling a trajectory on which a controlled object moves and for controlling a load on the trajectory. [Background technology]

[0002] Non-Patent Document 1 formulates an optimization problem in which "a constraining trajectory and a torque limit are used as constraint conditions, and a control input is obtained to move toward the constraining trajectory in the shortest time," and calculates a solution.

[0003] Patent Document 1 and Non-Patent Document 2 generate a potential field that guides the position of the robot's hand along a path. Generating such a potential field requires superposition and weight adjustment of many potential fields whose elements are kernel Gaussian functions. Potential designs include making the slope of the valley cross section steeper to strengthen the constraint on the path, and increasing the drop in the path at the valley bottom to increase the propulsion force along the path. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] US11554485B2 [Non-patent literature]

[0005] [Non-Patent Document 1] “An Efficient Robot Arm Control Under Geometric Path Constraints” [Non-patent document 2] “Learning Potential Functions from Human Demonstrations with Encapsulated Dynamic and Compliant Behaviors” [Non-patent document 3] Kiyoshi Ohishi, Yuzuru Ohba, Seiichiro Katsura “Kinematics and Dynamics of Motion Control Based on Acceleration Control” IEEJ Trans.IA,Vol.127,No6.2007 Summary of the Invention [Problem to be solved by the invention]

[0006] However, although the technology of Non-Patent Document 1 can constrain the trajectory of the controlled object, it does not anticipate adjusting the load on the movement on the trajectory.

[0007] Therefore, the techniques of Non-Patent Document 2 and Patent Document 1 have been proposed, but the more complex the potential field, the more overlapping and weight adjustment of element functions becomes necessary, which may increase the calculation load.

[0008] Furthermore, since the load on the orbit is applied through the conservative force of the potential field, it is not possible to apply load changes over time, which may limit the degree of freedom in load design.

[0009] The present invention has been made to solve the problems of the prior art, and aims to reduce the load calculation for a trajectory-constrained controlled object and ensure the degree of freedom in load design. [Means for solving the problem]

[0010] (1) The present invention is a device for constraining the trajectory of motion of a controlled object on a two-dimensional plane and controlling each actuator that applies a load on the trajectory, an energy controller that outputs a first acceleration reference value that constrains the trajectory by controlling a trajectory energy calculated from the position response of each of the actuators in accordance with a command value; a load controller that outputs a second acceleration reference value that controls the load applied along the trajectory based on a command value; an acceleration reference value calculation unit that calculates an acceleration reference value for each of the actuators by reflecting a unit vector in a normal direction of the iso-energy line in the first acceleration reference value and a unit vector in a tangential direction of the iso-energy line in the second acceleration reference value, and adding up the two values; and an acceleration control unit that calculates a torque command value for each of the actuators from an acceleration reference value of each of the actuators.

[0011] (2) In one aspect of the present invention, the orbital energy E (E=yx) is calculated from the position response [x, y] of the controlled object. 2 " an orbital energy calculator that calculates The energy controller matches the orbital energy E with the command value (zero) to create an explicit function "y = x 2 Calculating the first acceleration reference value that constrains the trajectory of The load controller is characterized by calculating the second acceleration reference value that generates a load in a tangential direction of an iso-energy line of the orbital energy E.

[0012] (3) Another aspect of the present invention is to provide a trajectory energy calculator that calculates trajectory energy E from the position response [x, y] of the controlled object, The trajectory energy calculator receives the trajectory energy that satisfies an implicit function "f(x, y) = 0" and the command value, and calculates the first acceleration reference value that constrains the trajectory on the trajectory of the implicit function. The load controller is characterized by calculating the second acceleration reference value that generates a load in the tangent direction of the isoenergy line when the orbital energy E is "E=f(x, y)".

[0013] (4) In yet another embodiment of the present invention, an orbital energy calculator that calculates orbital energy E from the position response [x, y] of the controlled object; The load controller The reaction force value of the actuator (Equation 24) is input, Calculate the reaction force in the tangential direction of the iso-energy line using Equation 26, The second acceleration reference value of Equation 25 is calculated.

[0014]

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[0015]

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[0016] "e s ” = unit vector tangential to the isoenergy line "F s res ” = tangential reaction force of the isoenergy line

[0017]

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[0018] "F s cmd ” = Load force command value on orbit "C f ” = Force control gain (5) In yet another embodiment of the present invention, The load controller "F" in the formula 26 s res = 0" The second acceleration reference value is calculated using Equation 27.

[0019]

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[0020] (6) In yet another embodiment of the present invention, The control object is The actuator includes: An electric motor for rotational motion on the x-axis, an electric motor for linear motion in the y-axis; Equipped with The mode conversion unit converts the position response "x, y" of each of the electric motors into the position response "x1, x2" of the actuator, The present invention is characterized in that the motion of each of the above exercises is constrained and a load is applied. [Effects of the Invention]

[0021] According to the present invention, it is possible to reduce the load calculation for a controlled object that is trajectory constrained and ensure the degree of freedom in load design. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 is a block diagram of a first embodiment. [Figure 2] (a) is a block diagram of the energy controller, (b) is a block diagram of the load controller, (c) is a block diagram of the acceleration control section, and (d) is a block diagram of the acceleration control section using a disturbance observer. [Figure 3] Graph showing isoenergy lines in Example 1. [Figure 4] Graph showing energy contours in Example 2. [Figure 5] 10(a) is a block diagram of the third embodiment, and FIG. 10(b) is a detailed diagram of the load controller (control of the load force) of the third embodiment. [Figure 6] FIG. 1 is a perspective view of a fitness machine used in a simulation. [Figure 7] Configuration diagram of the simulation target. [Figure 8] Simulation operation diagram. [Figure 9] 10A is a graph showing the response position of each degree of freedom of the simulation target in time series, and FIG. 10B is a graph showing the command value and response value of the orbital energy in Example 3. [Figure 10] Graph showing the plot in the "xy plane" of Example 3. DETAILED DESCRIPTION OF THE INVENTION

[0023] A load control device according to an embodiment of the present invention will now be described. This load control device relates to motion control of a robot to be controlled. Specifically, the device constrains the motion of a specific position of the robot on a trajectory and controls the load applied to the motion on the trajectory.

[0024] This allows an appropriate load to be applied to the robot's operator, making it possible to implement motion constraints appropriate for fitness training movements or games when used as a game controller, for example. [Example]

[0025] A load control device according to a first embodiment will be described with reference to Figures 1 and 2. In Figure 1, reference numeral 1 denotes the load control device of this embodiment, and reference numeral 10 denotes a controlled object. This load control device 1 is often mounted on the controlled object 10.

[0026] The object to be controlled is assumed to be a robot with multiple degrees of freedom that can control the position and force of the hand. The load control device 1 controls the movement on a two-dimensional plane along a straight line (y = x 2 ) trajectory constraints and load control are performed.

[0027] <Configuration example> The load control device 1 is configured by a computer, and as shown in FIG. 1, it implements a trajectory energy calculator 2, an energy controller 3, a load controller 4, an acceleration reference value calculator 5, an acceleration controller 6, and a differentiator 7.

[0028] The trajectory energy calculator 2 calculates the trajectory energy E from the position response [x, y] of each actuator of the control target 10. In this embodiment, the calculated trajectory energy E is as shown in Equation 1.

[0029]

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[0030] The energy controller 3 calculates the input of the orbit constraint, i.e., the acceleration reference value (Equation 2), by controlling the orbit energy E according to the command value. Here, the command value is determined in advance and is output to the load controller 4 simultaneously with the output of the orbit energy E from the orbit energy calculator 2.

[0031]

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[0032] In this embodiment, the command value is set to zero, and the energy controller 3 performs, for example, PD control of the orbital energy. The case of PD control will be explained based on FIG. 2(a). In FIG. 2(a), "d / dt" indicates the derivative with respect to time, and "K p " · "K d " indicates the proportional gain and the differential gain, respectively, and the acceleration reference value of Equation 2 is calculated as Equation 3.

[0033]

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[0034] The load controller 4 calculates an acceleration reference value (Equation 7) for controlling the load applied along the orbit in accordance with the command value. This command value is also determined in advance and is output to the load controller 4 simultaneously with the output of the orbit energy E from the orbit energy calculator 2.

[0035]

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[0036] For example, the load controller 4 applies a desired load such as a viscous load. In the case of a viscous load, the velocity on the orbit (Equation 4) is required, but it can be calculated as Equation 5.

[0037]

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[0038]

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[0039] Equation 6 in Equation 5 indicates the velocity of the actuator, and is expressed as "e s " indicates a vector in the tangential direction of the isoenergy contour described later, and the subscript "T" indicates transposition.

[0040]

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[0041] Figure 2(b) shows the block diagram for the case of viscous load. v " indicates the virtual viscosity coefficient that acts as a load, and the acceleration reference value (Equation 7) is output as Equation 8.

[0042]

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[0043] The acceleration reference value calculation unit 5 calculates the acceleration reference value (Equation 2) output from the energy controller 3 by adding a unit vector “e n " and the acceleration reference value (Equation 7) from the load controller 4 is multiplied by the unit vector "e s " is multiplied. The acceleration reference value (Equation 9) for each axis of the actuator is calculated by adding up each of these multiplied values.

[0044]

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[0045] In this case, each unit vector "e n "·"e s " is calculated by Equation 10. "norm" in Equation 10 indicates an operation to normalize as a vector of magnitude "1".

[0046]

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[0047] The acceleration control unit 6 calculates the torque command (torque command value) of each actuator shown in Equation 11 from the acceleration reference value (Equation 9) of each actuator.

[0048]

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[0049] FIG. 2(c) shows an example of the configuration of the acceleration control unit 6, in which the coordinate conversion unit 6a converts the acceleration reference value of Equation 9 into the angular acceleration reference value (Equation 12) of each axis of the motor. n " indicates the nominal function of each motor shaft, and the torque command value of Equation 11 is calculated using this function.

[0050]

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[0051] Fig. 2(d) shows the case where a disturbance observer is used, in which a coordinate conversion unit 6c converts the position response [x, y] of the actuator into a rotation angle "θ1, θ2" and outputs the result to a disturbance observer 6b. A general disturbance observer such as that described in Non-Patent Document 3 can be used for this disturbance observer 6b. Here, Equation 13 indicates an estimated value of the disturbance torque of each shaft of the motor, and a gravity term may be added when compensating for the disturbance torque.

[0052]

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[0053] The acceleration control unit 6 outputs the torque command value of the equation 11 to the controlled object 10. Here, the torque command value input to the controlled object 10 is expressed as the torque input of the equation 14.

[0054]

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[0055] The controlled object 10 outputs the actuator position response [x, y] from the torque input of Equation 14. A gravity compensation term may be added here, and the output actuator position response [x, y] is input to the orbital energy calculator 2, and the control of the controlled object 10 is repeated by the above-mentioned units 3 to 6.

[0056] <Control Principle> In this embodiment, as described above, a robot arm with multiple degrees of freedom is the controlled object 10, and the trajectory constraint of the hand and the load on the trajectory are controlled for the motion of the robot arm on a two-dimensional plane. This control is Control to constrain the motion trajectory of the robot arm of the control object 10 Load control on constrained orbits are executed in parallel.

[0057] (1) First, we will explain the control that constrains the trajectory of the motion. Here, we will use the explicit function "y = x 2 Let us consider the case where the object is constrained on the orbit of "y=x 2 " is "yx 2 =0". The orbital energy E can be rewritten as "E=yx 2 ", then if you control "E=0", "y=x 2 " relationship holds, and the trajectory can be constrained.

[0058] That is, the trajectory energy calculator 2 calculates the trajectory energy E from the response position of the robot arm, i.e., the response [x1, x2] of the hand position, and the energy controller 3 calculates the acceleration reference value (Equation 2) that makes the trajectory energy E coincide with the command value (=0) by using PD control or the like, thereby realizing "y = x 2 " Constrained control of the trajectory is realized.

[0059] In this case, the acceleration reference value (Equation 2) output by the energy controller 3 is a scalar value, so it must be converted into a vector value on a two-dimensional plane (xy plane) and then converted into a reference value for the actuator of the axis that makes up each plane.

[0060] This vector can be explained using the iso-energy line (see Figure 3) that shows the relationship between the orbital energy E and the robot arm's hand position [x, y]. The direction in which the orbital energy E changes is the direction in which the energy height in Figure 3 changes, and therefore is the normal direction to the iso-energy line. The unit vector in the normal direction to this iso-energy line can be calculated using Equation 15.

[0061]

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[0062] The "norm" in Equation 15 indicates an operation to normalize the vector to a magnitude of "1." Therefore, the acceleration reference value (Equation 2) output from the energy controller 3 is normalized by the unit vector "e n " can be converted into the x-axis and y-axis acceleration reference values ​​(Equation 9).

[0063] (2) Next, we will explain load control on a constrained trajectory. To apply a load on a trajectory, a force is generated in the tangential direction of the iso-energy line in Figure 3 without affecting the height direction of the iso-energy line. For example, when applying a viscous load with the control configuration of Figure 1, first the hand position response [x, y] of the robot arm is differentiated by differentiator 7, and the velocity [x · ,y · Next, the velocity in the tangential direction of the iso-energy line, "x · s "

[0064]

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[0065] Here, the unit vector "e s " can be calculated using Equation 17.

[0066]

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[0067] For the tangential direction, the load controller 4 calculates the tangential acceleration reference value (Equation 7) for applying the viscous load. This calculation uses Equation 18, and "D V " indicates the viscosity coefficient.

[0068]

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[0069] Here, since the acceleration reference value (Equation 7) output from the load controller 4 is a scalar value, the acceleration reference value calculation unit 5 converts it into a vector value on a two-dimensional plane (xy plane) in the same way as the trajectory constraint, and converts it into the acceleration reference value (Equation 9) of the actuator of the axis that constitutes each plane. This conversion is performed by adding the unit vector "e" to the acceleration reference value (Equation 7) as described above. s " can be multiplied by

[0070] In this way, we calculate the acceleration reference value (Equation 2) (Equation 7) for multiplying the acceleration reference value required for orbital constraint on the "xy" axis and the load on the orbit. At this time, we use the unit vector "e s " "e n Since the acceleration references are orthogonal to each other, they do not interfere with each other.

[0071] Therefore, the vector values ​​of these acceleration reference values ​​can be summed to obtain the acceleration reference value (Equation 9) for each actuator. The acceleration reference value for each actuator is converted into a torque input (Equation 14) by the acceleration control unit 6 and input to each actuator, achieving trajectory control and force control of the robot arm's tip.

[0072] As a result, trajectory control and load control of the robot arm's hand can be achieved without superimposing and adjusting the weight of potential fields as in Non-Patent Document 2 and Patent Document 1, which makes it possible to reduce the calculation load. Also, there is no need to apply the load on the trajectory through the conservative force of the potential field, ensuring freedom in load design. [Example]

[0073] This embodiment differs from the first embodiment in the following points regarding the load adjustment and trajectory constraint simultaneous control on the implicit function curve "f(x, y)=0".

[0074] (1) The orbital energy calculator 2 is the same as in the first embodiment in that it calculates the orbital energy E from the position response [x, y] of the actuator. However, this embodiment differs in that the curve of the implicit function to be constrained is set to "f(x, y) = 0" and the orbital energy E is determined within the range where "f(x, y) = 0" is established, including the command value.

[0075] (2) The energy controller 3 is the same as in the first embodiment in that it calculates the orbit constraint acceleration reference value (Equation 2) by controlling the orbit energy. For example, it performs PD control of the orbit energy E. However, the command value is determined to be a value that satisfies "f(x, y) = 0" according to the definition of the orbit energy E, and the command value determined in this way is input to the energy controller 3.

[0076] In the first embodiment, the trajectory to be constrained is expressed by an explicit function, but in the second embodiment, a trajectory expressed by an implicit function is used. This makes it possible to realize control for applying a load while constraining the trajectory to a circle, ellipse, or other trajectory expressed by an implicit function.

[0077] This embodiment differs from the first embodiment in the way the energy is defined by the orbital energy calculator 2 and the way the command value input to the energy controller 3 is determined. For example, assume an ellipse with a major axis radius "a" and a minor axis radius "b". In this case, the ellipse is expressed by Equation 19.

[0078]

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[0079] If we rewrite equation 19 so that "f(x,y)=0", we get equation 20.

[0080]

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[0081] In this case, if the orbital energy E is defined as Equation 21 and the command value of the orbital energy E is determined so that "E-1 = 0" holds, the command value of the orbital energy E is obtained as "1." If the orbital energy E is defined as Equation 22, the command value of the orbital energy E is obtained as "zero."

[0082]

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[0083]

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[0084] In this way, by determining the orbital energy E and command value so that "f(x,y) = 0" holds, control that is constrained to the orbit of "f(x,y) = 0" becomes possible. Figure 4 shows the iso-energy contours when the orbital energy E is defined as Equation 21.

[0085] In this embodiment, as in the first embodiment, (A) orbital constraint by the energy controller 3 and (B) load adjustment on the orbit by the load controller 4 are executed. That is, in this embodiment, the normal vector "e" pointing perpendicularly to the iso-energy line is also executed. n ” and the tangent vector along the isoenergy line “e s Since the acceleration reference values ​​(Equation 2) and (Equation 7) output by the two devices 3 and 4 are orthogonal to each other and do not interfere with each other, the acceleration reference values ​​(Equation 2) and (Equation 7) output by the two devices 3 and 4 do not interfere with each other. [Example]

[0086] The load controller 4 of this embodiment differs from the first embodiment in that the load force to be applied is directly controlled by the force controller. When the reaction force is fed back to the load controller 4, the reaction force on the trajectory "F s " is required, but it can be calculated as Equation 23.

[0087]

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[0088] 5(a) represents the reaction force of the actuator applied by the operator (user). The reaction force in Equation 24 is a sensor response value or an estimated value.

[0089]

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[0090] The details of the load controller 4 will be explained based on FIG. 5(b). s cmd ” indicates the command value of the load force on the orbit, and “C f " indicates the force control gain, and the acceleration reference value of Equation 7 is calculated as Equation 25.

[0091]

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[0092] Here, the load controller 4 in the first and second embodiments is mainly intended to control viscous loads, but the load controller 4 in this embodiment directly controls the load force. The control of the load force on a constrained orbit will be described below.

[0093] To apply a load on the trajectory, it is sufficient to generate a force in the tangential direction of the iso-energy lines shown in Figures 3 and 4 without affecting the height direction of the iso-energy lines. The control configuration in Figure 5 shows the configuration when applying a load force directly. First, the reaction force value (Equation 24) is obtained from the force sensor and reaction force estimator at the tip of the robot arm. Next, the reaction force in the tangential direction of the iso-energy lines, "F s res " is calculated using Equation 26.

[0094]

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[0095] Here, "e s " indicates the unit vector in the tangential direction of the isoenergy line, and the same subscript "T" indicates transposition. The tangential load force is directly controlled by the load controller 4 using the force controller, and the acceleration reference value (Equation 7) in Figure 5(b) is calculated using Equation 25.

[0096] As in the first embodiment, the acceleration reference value (Equation 7) output from the load controller 4 is a scalar value, so it is converted into a vector value on a two-dimensional plane (xy plane) as in the case of trajectory constraint, and then converted into the acceleration reference value (Equation 9) of the actuator of the axis that constitutes each plane.

[0097] In this embodiment, the reaction force "F s In order to calculate ", it is necessary to obtain the sensor response value or estimated value of the reaction force. If it is difficult to obtain these values, res = 0" and can be approximated by Equation 27.

[0098]

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[0099] <Simulation example> As described above, according to the first embodiment, it is possible to simultaneously realize constraint control to a trajectory expressed by an explicit function and load control on the trajectory, while according to the second embodiment, it is possible to handle a trajectory expressed by an implicit function, and according to the third embodiment, it is also possible to directly control the load force on the trajectory. Below, a simulation example applied to the fitness machine of Figs. 6 to 8 will be described.

[0100] (1) Example of fitness machine configuration As shown in FIG. 6, fitness machine 20 includes chair 23 on which a user (trainee) sits, left and right operating units (grips) 36 that the user grasps and operates, and mechanism units 21 and 22 that are movable along three axes (X-axis, Y-axis, and Z-axis). Mechanism units 21 and 22 are arranged on the left and right sides of chair 23.

[0101] Here, an example will be described in which the mechanical unit 21 in Fig. 7 is applied to a robot as the controlled object 10. In Fig. 7, x indicates rotation around the X axis, y indicates linear motion along the Y axis, and z indicates rotation around the Z axis.

[0102] The mechanism 21 includes a linear motion mechanism 34 that linearly moves the grip 36 in the y direction, and a rotation mechanism that rotates the linear motion mechanism 34 in the x and y directions, each of which is equipped with motors 38 to 39. These motors 37 to 39 correspond to the actuators of the controlled object 10 in this simulation.

[0103] Specifically, it comprises a vertically long box-shaped housing 31 erected on a rectangular base, a bracket 30 rotatably supported on the housing 31, and a linear motion mechanism 34 rotatably supported on the bracket 30.

[0104] A motor 39 is housed in the upper part of the housing 31. The bracket 30 is supported on the shaft of this motor 39 so as to be rotatable in the x direction. This forms a rotation mechanism that rotates the linear motion mechanism 34 along the x axis, and the load of the motor 39 is applied to the rotation of the bracket 30 in the same direction.

[0105] A motor 38 is fixed to the upper end of the bracket 30. The rear end of the arm portion 34a of the linear motion mechanism 34 is journaled to the shaft of this motor 38 so as to be rotatable in the y direction. This forms a rotation mechanism that rotates the linear motion mechanism 34 in the y direction, and the load of the motor 38 is applied to the rotation of the arm portion 34a in the same direction.

[0106] The linear motion mechanism 34 includes a motor 37 attached to the rear end of the arm portion 34a, a slider (movable element) 35 to which a grip 36 is fixed, and a ball screw mechanism (not shown) that applies a load from the motor 37 to the linear motion of the slider 35 along the z direction.

[0107] (2) Simulation method In this simulation, the degree of freedom of the linear motion mechanism 34 driven by motor 37 in Figure 7 (linear motion degree of freedom in the y direction) was defined as "linear," the rotational degree of freedom in the z direction driven by motor 38 was defined as "rotary1," and the rotational degree of freedom in the x direction driven by motor 39 was defined as "rotary2."

[0108] As shown in Fig. 8, the angle of "rotary1" was set to "90°" and the linear motion mechanism 34 was fixed vertically by position control. In addition, the control of Example 3 (control without reaction force feedback of Equation 27) was verified on the "two-dimensional xy plane" composed of "linear" and "rotary2".

[0109] The load controller 4 applies a constant force load, and the energy controller 3 is implemented so that the trajectory constraint is a quadratic function on a two-dimensional plane. In this case, (x, y) in Figure 7 corresponds to the actuator position response (x1, x2) in Figure 1.

[0110] (3) Simulation results First, the time series results of the simulation of Example 1 will be explained based on Figure 9. The results in Figure 9(a) show the position response of each degree of freedom, which changes at an accelerated rate, and reasonable results were obtained. Figure 9(b) shows the orbital energy command value (Ecmd) and response value (Eres), and the error is almost zero in the plot of the range of "±1 mm," indicating that the control target is fully achieved.

[0111] Next, Figure 10 shows a plot on the "xy plane," where the actual trajectory of the simulation almost overlaps with the desired trajectory, confirming the achievement of trajectory constraint. [Explanation of symbols]

[0112] 1...Load control device 2...Orbital energy calculator 3...Energy controller 4...Load controller 5...Acceleration reference value calculation section 6...Acceleration control section 6a, 6c... Coordinate conversion section 6b...Disturbance observer 10...Control object 20...Fitness machine 21,22... Mechanism section 23...Chair 30…Bracket 31...Case 34...Linear motion mechanism 35...Slider 36...Grip 37~39...Motor

Claims

1. An apparatus for constraining a trajectory of motion of a controlled object on a two-dimensional plane and controlling each actuator that applies a load on the trajectory, comprising: an energy controller that outputs a first acceleration reference value that constrains the trajectory by controlling a trajectory energy calculated from the position response of each of the actuators in accordance with a command value; a load controller that outputs a second acceleration reference value that controls the load applied along the trajectory based on a command value; an acceleration reference value calculation unit that calculates an acceleration reference value for each of the actuators by reflecting a unit vector in a normal direction of the iso-energy line in the first acceleration reference value and a unit vector in a tangential direction of the iso-energy line in the second acceleration reference value, and adding up the two values; an acceleration control unit that calculates a torque command value for each of the actuators from an acceleration reference value of each of the actuators; A load control device comprising:

2. From the position response [x, y] of the controlled object, the orbital energy E "E = y - x ２ " an orbital energy calculator that calculates The energy controller matches the orbital energy E with the command value (zero) to realize the explicit function "y = x ２ " while calculating the first acceleration reference value that constrains the trajectory of The load controller calculates the second acceleration reference value that generates a load in a tangential direction of an isoenergy line of the orbital energy E.

2. The load control device according to claim 1.

3. an orbital energy calculator that calculates orbital energy E from the position response [x, y] of a control object; The trajectory energy calculator receives the trajectory energy that satisfies an implicit function "f(x, y) = 0" and the command value, and calculates the first acceleration reference value that constrains the trajectory on the trajectory of the implicit function. The load controller calculates the second acceleration reference value that generates a load in a tangential direction of an iso-energy line when the orbital energy E is set to "E=f(x, y)." 2. The load control device according to claim 1.

4. an orbital energy calculator that calculates orbital energy E from the position response [x, y] of a control object; The load controller The reaction force value of the actuator (Equation 24) is input, Calculate the reaction force in the tangential direction of the iso-energy line using Equation 26, 2. The load control device according to claim 1, wherein the second acceleration reference value is calculated using Equation 25. [0000] [Equation 26] "e s ” = unit vector in the tangent direction of the isoenergy line "F s rｅｓ ” = reaction force in the tangential direction of the isoenergy line [Equation 25] "F s ｃｍｄ ” = Load force command value on orbit "C f " = Force control gain

5. The load controller "F" in the formula 26 s rｅｓ = 0" 5. The load control device of claim 4, wherein the second acceleration reference value is calculated using Equation 27. [0000]

6. The control object is The actuator includes: an electric motor for rotary motion about the x-axis; an electric motor for linear motion in the y-axis; Equipped with The mode conversion unit converts the position response "x, y" of each of the electric motors into the position response "x" of the actuator. １ ,x ２ " 6. The load control device according to claim 2, wherein the load is applied by restricting the movement of each of the exercises.

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