JP7175445B2 - Axial torque controller for tire testing equipment - Google Patents

Description

The present invention relates to a shaft torque controller for tire testing equipment. More specifically, the present invention relates to a shaft torque controller for controlling the shaft torque of a tire driving shaft of a tire to be tested in a tire testing apparatus.

Many vehicles, such as four-wheeled automobiles and motorcycles, are equipped with at least two tires. Tire performance varies depending on various factors such as its material, shape, air pressure, contact load with the road surface, and temperature. As a tire testing device for evaluating the performance of such tires, while rotating the tire on a simulated road surface such as a belt or roller, while adjusting the camber angle, slip angle, vertical load, etc., It is known to measure applied force, rolling resistance, and the like. According to such a tire testing device, the performance of a single tire can be evaluated without mounting the tire on an actual vehicle or actually driving the actual vehicle on a test course, thus reducing the time required for testing. is short and convenient.

In recent years, the information obtained by using actual tires in the above-mentioned tire test equipment is used as input, and the behavior of the entire vehicle is reproduced by simulation using a vehicle model, and the information obtained by this simulation is fed back to an actuator that moves an actual tire in a tire testing apparatus (see, for example, Patent Document 1). Such a testing device that incorporates a real device (in the above example, a real tire and its tire testing device) into the simulation is also called a HIL (Hardware In the Loop) simulator.

In such a test device, by inputting information obtained by a simulation that reproduces the behavior of the vehicle into the tire test device, it is possible to test tires under conditions closer to actual running conditions. In addition, tires are composed of composite materials such as rubber, organic fibers, and metals, and are elastic bodies that undergo large changes. Building a model is difficult. On the other hand, according to the above test equipment, it is possible to accurately analyze vehicle behavior under conditions closer to actual driving conditions by reproducing vehicle behavior through simulation using information obtained from actual tires. Become.

JP 2018-146421 A

By the way, in the test device, the load inertia of the tire driving motor that drives the actual tire changes greatly depending on whether the actual tire is in contact with the simulated road surface or not. More specifically, when the actual tire is in contact with the simulated road surface, the tire drive motor bears the inertia of both the tire inertia of the actual tire and the simulated road surface with which the actual tire is in contact. bears only tire inertia if it is not in contact with the ground. In this way, in the test equipment, the resonance frequency detected by the shaft torque sensor of the tire drive shaft that connects the tire drive motor and the actual tire can change greatly, so it is necessary to stably control the shaft torque of the tire drive shaft. However, Patent Document 1 does not sufficiently consider this point.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a shaft torque controller for a tire testing apparatus that can stably perform shaft torque control regardless of tire contact conditions.

(1) A shaft torque controller (for example, a tire shaft torque controller 62 to be described later) according to the present invention is connected to a tire drive shaft (for example, a tire drive shaft 42 to be described later) of a tire (for example, a tire T to be described later). and a shaft torque sensor (for example, a tire shaft torque sensor 40 described later) that generates a shaft torque detection signal (Tsh) corresponding to the shaft torque of the tire drive shaft. ), and a tire grounding device (for example, a tire support mechanism 3 and a vertical load adjustment motor 37, which will be described later) that grounds and separates the tire from a simulated road surface (such as a simulated road surface 25a, which will be described later). Control input to the tire drive motor based on the shaft torque detection signal (Tsh) and a shaft torque command signal (Tsh_cmd) corresponding to the shaft torque detection signal, with a test device (for example, a tire test device S described later) as a controlled object. (Itire). The shaft torque controller has an integrator (for example, an integrator 622 to be described later) that generates a first input (I1) by integrating a deviation (etsh) between the shaft torque command signal and the shaft torque detection signal. ), a low-pass filter (for example, a low-pass filter 623 to be described later) that generates a second input (I2) by attenuating high-frequency components and passing low-frequency components from the shaft torque detection signal (Tsh); and a control input generation unit (for example, a tire shaft torque command calculation unit 624 described later) that generates the control input (Itire) based on the first input (I1) and the second input (I2). do.

(2) In this case, the integration gain of the integrator and the plurality of control gains that characterize the input/output characteristics of the low-pass filter are obtained by: The following polynomial Pr(s) characterized by the response frequency fr determined based on the moment of inertia of the tire drive motor and the torsional stiffness of the tire drive shaft and predetermined coefficients p1, p2, p3, p4, p5 is preferably set. In the following description, "s" is the Laplacian operator.

(3) In this case, the response frequency fr is preferably set by the following equation, where J2 is the moment of inertia of the tire drive motor and K12 is the torsional rigidity of the tire drive shaft.

(4) In this case, it is preferable that the transfer function GLPF(s) of the low-pass filter is expressed by the following equation using four control gains (Kp, Kd, a1, a2).

(5) In this case, the integration gain Ki of the integrator and the four control gains (Kp, Kd, a1, a2) are obtained by dividing the response frequency fr and the plurality of coefficients (p1, p2, p3, p4, p5) into is preferably set by the following formula using

(1) A shaft torque controller of the present invention comprises an integrator that generates a first input by performing an integral operation of a deviation between a shaft torque command signal and a shaft torque detection signal detected by a shaft torque sensor; a low pass filter for generating a second input by attenuating high frequency components and passing low frequency components from the torque sense signal; and a tire coupled to a tire drive shaft of the tire based on the first and second inputs. a control input generator that generates a control input for the drive motor. According to the shaft torque controller of the present invention, by generating the control input for the tire drive motor based on the first input and the second input, high torque is generated when the tires are in contact with the simulated road surface. It is possible to control the shaft torque of the tire drive shaft in a responsive manner and stably though the response is low when the tires are not in contact with the simulated road surface.

(2) In the shaft torque controller of the present invention, the integral gain of the integrator and the plurality of control gains that characterize the input/output characteristics of the low-pass filter are the characteristic polynomial of the closed-loop transfer function of the control circuit composed of the integrator and the low-pass filter. is the polynomial Pr(s) shown in the above equation (1) characterized by the response frequency fr determined based on the moment of inertia of the tire drive motor and the torsional stiffness of the tire drive shaft and the predetermined coefficients p1 to p5 set. According to the shaft torque controller of the present invention, the integral gain of the integrator and the control gain of the low-pass filter are adjusted so that the characteristic polynomial of the closed loop transfer function becomes a fifth-order polynomial as shown in the above equation (1). Thus, the shaft torque of the tire drive shaft can be controlled with high response when the tire is in contact with the simulated road surface, and with low response when the tire is not in contact with the simulated road surface, but stably.

(3) In the shaft torque controller of the present invention, the response frequency fr, which indicates the response performance of the shaft torque control, is determined by the above equation (2) based on the known moment of inertia J2 of the tire drive motor and torsional rigidity K12 of the tire drive shaft. ). Thus, according to the shaft torque controller of the present invention, the response is high when the tire is in contact with the simulated road surface, and the response is low but stable when the tire is not in contact with the simulated road surface. The shaft torque of the tire drive shaft can be controlled.

(4) In the shaft torque controller of the present invention, the transfer function GLPF(s) of the low-pass filter is set by the above equation (3) using the four control gains (Kp, Kd, a1, a2). According to the shaft torque controller of the present invention, the low-pass filter is set so that the characteristic polynomial of the closed-loop transfer function of the control circuit composed of the integrator and the low-pass filter becomes a fifth-order polynomial as shown in the above equation (1). By adjusting the control gains (Kp, Kd, a1, a2), the response is high when the tires are in contact with the simulated road surface, and low when the tires are not in contact with the simulated road surface. can stably control the shaft torque of the tire drive shaft.

(5) In the shaft torque controller of the present invention, the integration gain Ki of the integrator and the control gains (Kp, Kd, a1, a2) of the low-pass filter are set to the response frequency fr and the plurality of coefficients (p1, p2, p3, p4 , p5) are set according to the above equations (4-1) to (4-5). As a result, according to the shaft torque controller of the present invention, the characteristic polynomial of the closed loop transfer function satisfies the above equation (1). When the tire is not in contact with the simulated road surface, the torque of the tire drive shaft can be stably controlled although the response is low.

It is a figure showing composition of a tire testing device concerning one embodiment of the present invention. It is a figure which shows typically several motors and several sensors provided in a tire testing apparatus. FIG. 4 is a diagram showing a slip angle on a simulated road surface; FIG. 4 is a diagram showing camber angles on a simulated road surface; FIG. 4 is a diagram showing forces acting on a tire moving on a simulated road surface; FIG. 3 is a diagram showing the configuration of a control module related to tire shaft torque control in the general control device; FIG. 4 is a diagram showing the configuration of a control circuit of a tire shaft torque controller; FIG. 5 is a diagram showing a response waveform of a tire shaft torque detection signal when a tire shaft torque command signal that changes stepwise is input to a tire shaft torque controller while the tire is in contact with the simulated road surface. FIG. 5 is a diagram showing a response waveform of a tire shaft torque detection signal when a tire shaft torque command signal that changes stepwise is input to a tire shaft torque controller while the tire is not in contact with the simulated road surface.

An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing the configuration of a tire testing apparatus S according to this embodiment.
FIG. 2 is a diagram schematically showing a plurality of motors and a plurality of sensors provided in the tire testing device S. FIG.

The tire testing apparatus S includes a tire testing unit 1 that uses a plurality of motors to apply various external forces to the actual tire T to move the tire T, and a general control device 6 that controls the tire testing unit 1. .

The tire testing device S inputs information obtained by using the actual tire T in the tire testing unit 1 to the general control device 6, and the general control device 6 generates a virtual vehicle with the tire T as a component. The behavior is reproduced by simulation using a model, and the information obtained by this simulation is fed back to the tire testing unit 1. In the following description, the virtual vehicle assumed in the tire testing apparatus S is a four-wheeled vehicle using an engine as a power source, but the number of wheels and the power source of the virtual vehicle are not limited to these. The tires T are drive wheels to which power from the power generation source of the virtual vehicle is transmitted, and are steerable wheels whose steering angle can be changed by steering that can be operated by the driver. The role of the tire T in the vehicle is not limited to this.

The tire testing unit 1 includes a tire T mounted on a rim, a road surface simulating device 2 in contact with the tire T, and rotating the tire T about its hub while rotating the tire T against the road simulating device 2 at a predetermined angle. and a tire support mechanism 3 that supports in a posture.

The road surface simulator 2 includes a base 21 fixed to a horizontal floor surface, and a belt unit 22 rotatably provided around a rotation axis OSA along a vertical direction perpendicular to the base 21. , a slip angle motor 23 (see FIG. 2) for rotating the belt unit 22 around a rotation shaft, and a slip angle sensor 29 (see FIG. 2).

The belt unit 22 includes a pair of cylindrical belt drums 24a and 24b rotatably provided, and these belt drums 24a . and an endless belt-like flat belt 25 that is stretched over the outer periphery of 24b. The outer peripheral surface of the flat belt 25 is processed to simulate an actual road surface. As a result, the vertically upper surface of the outer peripheral surface of the flat belt 25 serves as a simulated road surface 25a with which the tire T contacts. The rotation axes of these belt drums 24a and 24b are parallel to each other and perpendicular to the rotation axis OSA.

The belt drum 24a includes a road surface driving motor 26 (see FIG. 2) whose output shaft is connected to the belt drum 24a, and a belt rotation speed sensor 27 (see FIG. 2) for detecting the rotation speed of the output shaft of the road surface driving motor 26. ), and a belt shaft torque sensor 28 (see FIG. 2) for detecting the shaft torque generated on the output shaft. The road surface driving motor 26 rotationally drives the drum 24a according to a command signal from the general control device 6 . As a result, the simulated road surface 25a flows along the road traveling direction FR in a plane perpendicular to the rotation axis OSA at a speed corresponding to the rotation speed of the belt drum 24a. The belt rotation speed sensor 27 detects the rotation speed of the output shaft, that is, the rotation speed of the belt drum 24a, and transmits a belt rotation speed detection signal ωbel corresponding to the detected value to the general control device 6. The belt shaft torque sensor 28 also detects the shaft torque generated on the output shaft and transmits a belt shaft torque detection signal Tbel corresponding to the detected value to the general control device 6 .

The slip angle motor 23 rotates the belt unit 22 about the rotation axis OSA in response to a signal from the general control device 6 . In the road surface simulator 2, the slip angle motor 23 is used to rotate the belt unit 22, so that, as shown in FIG. The slip angle, which is the angle α formed with the traveling direction FR, can be adjusted. The slip angle sensor 29 generates a slip angle detection signal θSA corresponding to the slip angle and transmits it to the general control device 6 .

The tire support mechanism 3 includes a pair of pedestals 31a and 31b fixed to the floor at both ends in the road traveling direction FR, which is the belt feed direction of the belt unit 22, and an arcuate structure supported at both ends by the pedestals 31a and 31b. , a rod-shaped support arm 35 supported by the frame 33 , and a rotary drive unit 36 provided at the tip of the arm 35 .

The frame 33 extends vertically above the flat belt 25 . Both ends of the frame 33 are rotatably supported by pedestals 31 a and 31 b about a rotation axis OCA substantially perpendicular to the extending direction of the flat belt 25 . Also mounted on the pedestal 31a are a camber angle adjusting motor 32 (see FIG. 2) that drives the frame 33 to rotate about the rotation axis OCA, a camber angle sensor 34 that detects the angle of the frame 33 with respect to the simulated road surface 25a, is provided. The camber angle adjustment motor 32 rotates the frame 33 around the rotation axis OCA in response to a command signal from the general control device 6 . In the tire support mechanism 3, the camber angle adjustment motor 32 is used to rotate the frame 33 and the support arm 35 supported by the frame 33, thereby adjusting the rotation axis of the tire T on the simulated road surface 25a as shown in FIG. 3B. The camber angle, which is the angle between R and the simulated road surface 25a, that is, the angle β between the normal to the simulated road surface 25a and the plane perpendicular to the rotation axis R, can be adjusted. The camber angle sensor 34 generates a camber angle detection signal θCA corresponding to the camber angle and transmits it to the general control device 6 .

The support arm 35 extends along the vertical direction perpendicular to the simulated road surface 25a. A base end portion of the support arm 35 is supported by the frame 33 so as to be slidable along the extending direction of the support arm 35 . The frame 33 is provided with a vertical load adjustment motor 37 (see FIG. 2) that displaces the support arm 35 along the extension direction of the support arm 35 . The vertical load adjustment motor 37 displaces the support arm 35 along its extending direction in response to a command signal from the general control device 6 . In the tire support mechanism 3, the vertical load adjustment motor 37 is used to displace the support arm 35, thereby making the tire T contact the simulated road surface 25a or separating the tire T from the simulated road surface 25a. Further, in the tire support mechanism 3, by displacing the support arm 35 using the vertical load adjustment motor 37, it is also possible to adjust the vertical load, which is the force that presses the tire T against the simulated road surface 25a.

The rotary drive unit 36 rotatably supports the tire T at the tip of the support arm 35 . As shown in FIG. 2 , the rotary drive unit 36 includes a tire drive motor 38 , a force sensor 39 , a tire shaft torque sensor 40 , a tire rotation speed sensor 41 and a tire drive shaft 42 .

The tire drive shaft 42 extends substantially perpendicular to the support arm 35 and connects the tire drive motor 38 and the tire T. As shown in FIG. The tire drive shaft 42 has a distal end connected to the hub of the tire T, and a proximal end connected to an output shaft of the tire drive motor 38 . The tire drive motor 38 rotates the tire T according to a command signal from the general control device 6 . The tire rotation speed sensor 41 detects the rotation speed of the output shaft of the tire drive motor 38, that is, the rotation speed of the tire T, and transmits a tire rotation speed detection signal ωtire corresponding to the detected value to the general control device 6.

The force sensor 39 detects force acting on the tire T moving on the simulated road surface 25a. As the force sensor 39, for example, a 5-component force meter that detects 5 of the 6-component forces acting on the tire T as shown in FIG. 3C is used. More specifically, the force sensor 39 detects the longitudinal force detection signal Fx corresponding to the longitudinal force along the traveling direction axis X of the tire T and the lateral force corresponding to the lateral force along the lateral axis Y of the tire T. A detection signal Fy, a vertical load detection signal Fz corresponding to the vertical load along the longitudinal axis Z of the tire T, an overturning detection signal Mx corresponding to the moment about the traveling direction axis X of the tire T, and the tire T and a self-aligning torque detection signal Mz corresponding to the moment about the longitudinal axis of . In the following description, the five signals Fx, Fy, Fz, Mx, and Mz generated by the force sensor 39 are collectively referred to as "F5".

The tire shaft torque sensor 40 generates a tire shaft torque detection signal Tsh corresponding to the shaft torque of the tire drive shaft 42, that is, the moment about the lateral axis of the tire T, and the tire shaft torque detection signal Tsh is sent to the general control device 6. Send to

The general control device 6 A/D converts input signals sent from various sensors 27, 28, 29, 34, 39, 40, 41, etc., and inputs them to various motors 23, 26, 32, 37, 38, etc. I/O interface for D/A conversion of the output signal, CPU for executing arithmetic processing according to various programs, storage means such as ROM and RAM for storing various data, and for the operator to input various commands. It is a computer configured by hardware such as operable input means and display means for displaying operation results and the like in a manner that can be visually recognized by the operator.

The general control unit 6 performs a simulation that reproduces the behavior of a virtual vehicle with tires T as a component based on input signals transmitted from various sensors 27, 28, 29, 34, 39, 40, 41, and the like. Along with performing calculations, output signals to various motors 23, 26, 32, 37, 38, etc. are generated by this simulation calculation, and input to various motors 23, 26, 32, 37, 38, etc. FIG.

FIG. 4 is a diagram showing the configuration of a control module related to tire shaft torque control acting on the tire drive shaft 42 in the general control device 6. As shown in FIG. The general control device 6 includes a tire-driven vehicle model calculator 61 and a tire shaft torque controller 62 as control modules related to tire shaft torque control.

Based on the engine torque command signal Teng and the tire rotation speed detection signal ωtire transmitted from the tire rotation sensor 41, the tire driven vehicle model calculation unit 61 calculates a tire shaft torque command signal Tsh_cmd corresponding to the target for the tire shaft torque detection signal Tsh. and inputs this tire shaft torque command signal Tsh_cmd to the tire shaft torque controller 62 . Here, the engine torque command signal Teng is a command signal for the engine torque generated by the engine mounted on the virtual vehicle, and corresponds to the opening of the accelerator pedal in the virtual vehicle. This engine torque command signal Teng is calculated by a simulation calculation (not shown).

2. Description of the Related Art In general vehicles, various spring elements such as clutches and drive shafts are present in a drive train that transmits power generated by an engine to tires. Therefore, when the engine torque is suddenly changed, the shaft torque for driving the tire oscillates due to the torsional vibration of these spring elements. Therefore, in the tire-driven vehicle model calculation unit 61, based on the engine torque command signal Teng and the tire rotation speed detection signal ωtire, a calculation simulating the operation of the drive train in the virtual vehicle is performed to generate the tire shaft torque command signal Tsh_cmd. .

Based on the tire shaft torque detection signal Tsh and the tire shaft torque command signal Tsh_cmd, the tire shaft torque controller 62 generates a motor torque command signal Itire corresponding to a control input to the tire drive motor 38, and outputs this motor torque command. A signal Itire is input to the tire drive motor 38 .

FIG. 5 is a diagram showing the configuration of the control circuit of the tire shaft torque controller 62. As shown in FIG. The tire shaft torque controller 62 includes a shaft torque deviation calculator 621, an integrator 622, a low-pass filter 623, and a tire shaft torque command calculator 624, and uses these to generate a motor torque command signal Itire. do.

Shaft torque deviation calculator 621 generates shaft torque deviation signal etsh by subtracting tire shaft torque detection signal Tsh from tire shaft torque command signal Tsh_cmd, and inputs this shaft torque deviation signal etsh to integrator 622 .

The integrator 622 generates a first input I1 by performing an integration operation on the shaft torque deviation signal etsh multiplied by a predetermined integral gain Ki, and inputs this first input I1 to the tire shaft torque command calculation unit 624. . A transfer function GI(s) representing the input/output characteristics of the integrator 622 is expressed by the following equation (5) using the integral gain Ki and the Laplace operator s.

Low-pass filter 623 generates a second input I2 by attenuating high frequency components and passing low frequency components from shaft torque detection signal Tsh, and inputs this second input I2 to tire shaft torque command calculation unit 624. . A transfer function GLPF(s) representing the input/output characteristics of the low-pass filter 623 is expressed by the following equation (6) using four predetermined control gains (Kp, Kd, a1, a2) and the Laplace operator s. .

The tire shaft torque command calculation unit 624 generates a motor torque command signal Itire based on the first input I1 and the second input I2 and inputs the motor torque command signal Itire to the tire drive motor 38 . More specifically, tire shaft torque command calculator 624 generates motor torque command signal Itire by subtracting second input I2 from first input I1.

Next, a procedure for setting the integral gain Ki and the four control gains (Kd, Kp, a1, a2) characterizing the input/output characteristics of the tire shaft torque controller 62 will be described. As described above, in the tire testing apparatus S, the tire T can be brought into contact with the simulated road surface 25a by the vertical load adjusting motor 37, or separated from the simulated road surface 25a. Therefore, the inertia of the tire drive motor 38 changes greatly depending on whether the tire T is in contact with the simulated road surface 25a or not, so that the resonance frequency detected by the tire shaft torque sensor 40 changes significantly. can.

Therefore, in the tire shaft torque controller 62, the integral gain Ki and the four control gains (Kd, Kp, a1 , a2), the characteristic polynomial Pr(s) of the closed-loop transfer function of the control circuit formed by the tire shaft torque controller 62 is expressed by the following equation (7), with predetermined coefficients (p1, p2, p3, p4 , p5) is set to be a fifth-order polynomial.

In the above equation (7), the coefficients (p1, p2, p3, p4, p5) are set by the tire axle torque controller 62 so that desired control characteristics are obtained. Also, in the above equation (7), “fr” is the response frequency that characterizes the response characteristic of the tire shaft torque controller 62 . More specifically, this response frequency fr is set by the following equation (8) using the moment of inertia J2 of the tire drive motor 38 and the torsional stiffness K12 of the tire drive shaft 42, which are known.

Under the above conditions, the integral gain Ki and the four control gains (Kd, Kp, a1, a2) are obtained by using the response frequency fr and the coefficients (p1, p2, p3, p4, p5), for example, by the following equation It is set by (9-1) to (9-5). That is, the following equations (9-1) to (9-5) are the integral gain Ki and four It is an example of a solution for control gains (Kd, Kp, a1, a2). Note that when the tire T is in contact with the simulated road surface 25a, the inertia acting on the tire drive motor 38 is sufficiently greater than the moment of inertia J2 of the tire drive motor 38. FIG. Therefore, in deriving the following equations (9-1) to (9-5), the moment of inertia of the tire T was approximated to be infinite.

Next, the effect of the tire shaft torque controller 62 according to this embodiment will be described with reference to FIGS. 6 and 7. FIG.
FIG. 6 shows the tire shaft torque when the tire shaft torque command signal Tsh_cmd (see the broken line in FIG. 6) that changes stepwise is input to the tire shaft torque controller 62 while the tire T is in contact with the simulated road surface 25a. 7 is a diagram showing a response waveform of a detection signal Tsh (see solid line in FIG. 6); FIG.

FIG. 7 shows the tire shaft torque when the tire shaft torque command signal Tsh_cmd (see the broken line in FIG. 7) that changes stepwise is input to the tire shaft torque controller 62 while the tire T is not in contact with the simulated road surface 25a. 8 is a diagram showing a response waveform of a detection signal Tsh (see solid line in FIG. 7); FIG.

As shown in FIG. 6, when the tire shaft torque command signal Tsh_cmd is stepwise changed to a positive predetermined value tstep at time t1, the tire shaft torque detection signal Tsh quickly changes to the tire shaft torque command without overshooting. Converge to signal Tsh_cmd.

As shown in FIG. 7, when the tire shaft torque command signal Tsh_cmd is stepwise changed to a positive predetermined value tstep at time t1, the tire shaft torque detection signal Tsh indicates that the tire T is in contact with the simulated road surface 25a. Although there is a delay compared to the case (see FIG. 6), it converges to the tire shaft torque command signal Tsh_cmd without overshooting.

As described above, according to the tire shaft torque controller 62 according to the present embodiment, when the tire T is in contact with the simulated road surface 25a, the response is high, and the tire T is not in contact with the simulated road surface 25a. In this case, the shaft torque of the tire drive shaft 42 can be stably controlled although the response is low.

As mentioned above, although one Embodiment of this invention was described, this invention is not limited to this. Detailed configurations may be changed as appropriate within the scope of the present invention.

S... Tire test device 1... Tire test unit T... Tire 2... Road surface simulator 25... Flat belt 25a... Simulated road surface 3... Tire support mechanism (tire grounding device)
37 Vertical load adjustment motor (tire grounding device)
36... Rotary drive unit 38... Tire drive motor 40... Tire shaft torque sensor (shaft torque sensor)
41... Tire rotation speed sensor 42... Tire drive shaft 6... Overall control device 61... Tire drive vehicle model calculation unit 62... Tire shaft torque controller (shaft torque controller)
621... Shaft torque deviation calculator 622... Integrator 623... Low-pass filter 624... Tire shaft torque command calculator (control input generator)

Claims (3)

A tire drive motor connected to a tire drive shaft of a tire, a shaft torque sensor for generating a shaft torque detection signal corresponding to the shaft torque of the tire drive shaft, and a grounding or separation of the tire from a simulated road surface. and a tire grounding device, wherein a control input is generated for the tire drive motor based on the shaft torque detection signal and a shaft torque command signal corresponding to the shaft torque detection signal. A torque controller,
an integrator that generates a first input by integrating a deviation between the shaft torque command signal and the shaft torque detection signal;
a low-pass filter for generating a second input by attenuating high frequency components and passing low frequency components from the shaft torque detection signal;
and a control input generator that generates the control input based on the first input and the second input. integral gain of the integratorKiand characterizing the input-output characteristics of the low-pass filterfourcontrol gain of(Kp, Kd, a1, a2)is the characteristic polynomial of the closed-loop transfer function of the control circuit composed of the integrator and the low-pass filter, givenresponse frequency fr and predetermined coefficients p1, p2, p3, p4, p5according to the following formula (1-1)is set to be the following polynomial Pr(s) characterized bybe,
The response frequency fr is set by the following formula (1-2), where J2 is the moment of inertia of the tire drive motor and K12 is the torsional rigidity of the tire drive shaft,
The integral gain Ki and the four control gains (Kp, Kd, a1, a2) are obtained by the following formula (1-3) using the response frequency fr and a plurality of coefficients (p1, p2, p3, p4, p5) to be set by (1-7) The axial torque controller of the tire testing apparatus according to claim 1, characterized by

3. Axial torque control for a tire testing apparatus according to claim 2, wherein the transfer function GLPF(s) of said low-pass filter is represented by the following equation using four control gains (Kp, Kd, a1, a2): vessel.

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