JP7432346B2 - Tire ground contact characteristic measurement device, tire ground contact characteristic measurement system, and tire ground contact characteristic measurement method - Google Patents

Description

The present invention relates to a tire ground contact characteristic measuring device, a tire ground contact characteristic measuring system, and a tire ground contact characteristic measuring method.

Conventionally, in technology to measure the ground contact characteristics such as stress distribution of tires that contact a rotating drum, a sensor embedded in the rotating drum measures the stress applied to the tire and synthesizes the stress that contacts the tire in a specific range. The stress distribution on the tire was measured.

Japanese Patent Application Publication No. 2014-021012

According to the technique described above, the resolution of the stress distribution in the direction of the rotation axis of the rotating drum (hereinafter simply referred to as the rotation axis direction) is limited by the distance between the sensors embedded in the rotation axis direction. Therefore, in order to increase the resolution in the direction of the rotation axis, it was necessary to narrow the distance between the embedded sensors in the direction of the rotation axis. The spacing between the sensors embedded in the rotating drum is limited by the size of the sensors.
That is, the conventional method has a problem in that the resolution in the rotation axis direction is limited by the physical size of the sensor.

The present invention has been made in view of the above situation, and an object of the present invention is to provide a tire ground contact characteristic measuring device, a tire ground contact characteristic measuring system, and a tire ground contact characteristic measuring method that can increase the resolution in the rotational axis direction. It is said that

A tire ground contact characteristic measuring device according to one aspect of the present invention includes: a cylindrical rotating drum rotatable around a rotating shaft; a drum driving means for rotating the rotating drum around the rotating shaft; and a cylindrical surface of the rotating drum. A sensor array is embedded in the cylindrical surface and measures the stress applied to the tire in contact with the cylindrical surface, the sensor array being arranged in tandem in the direction of the rotational axis of the cylindrical surface and capable of independently measuring stress. a plurality of sensor rows having a plurality of sensor rows located at mutually different positions in the rotating circumferential direction of the rotary drum, and the position of the stress measurement area of each of the plurality of sensor rows in the rotation axis direction is between the plurality of sensor rows. of the tread surface of the tire based on stress measured by stress measuring means arranged at different positions from each other and at least two of the plurality of sensor rows of the plurality of sensor rows included in the stress measuring means. a processing device that calculates a tire ground contact characteristic that is a characteristic in a ground contact region that contacts a rotating drum; an output device that outputs the tire ground contact characteristic that is calculated by the processing device; and a stress measuring region that is included in the sensor array that is measured. an interpolation unit that calculates stress as post-interpolated stress information by interpolation, the resolution of stress in the post-interpolated stress information is higher than the resolution of stress measured by the stress measurement area, and the processing device calculates the post-interpolated stress Tire ground contact characteristics, which are characteristics of the ground contact region of the tread surface of the tire that contacts the rotating drum, are calculated based on the stress with higher resolution, which is obtained by synthesizing the stress resolution in the information.

Further, in the tire ground contact characteristic measuring device according to one aspect of the present invention, the processing device includes a synthesis unit that calculates a composite tire ground contact characteristic based on stress measured by at least two of the sensor rows. Prepare more.

Furthermore, in the tire ground contact characteristic measuring device according to one aspect of the present invention, the synthesis section performs an interpolation process of interpolating in the direction of the rotation axis of the rotary drum based on the post-interpolation stress information calculated by the interpolation section. The synthetic tire ground contact characteristic is thereby calculated, and the output device outputs the synthetic tire ground contact characteristic calculated by the synthesis section.

Further, in the tire ground contact characteristic measuring device according to one aspect of the present invention, the interpolation is linear interpolation.

Further, in the tire ground contact characteristic measuring device according to one aspect of the present invention, the interpolation is spline interpolation.

Further, in the tire ground contact characteristic measuring device according to one aspect of the present invention, the stress measuring means includes a three-component force sensor capable of measuring ground contact force, width direction shear stress, and circumferential direction shear stress applied to the tire.

Further, a tire ground contact characteristic measuring system according to one aspect of the present invention includes the above-described tire ground contact characteristic measuring device, at least one of the displacement amount and acting force of a vehicle, and the displacement amount and acting force of a wheel included in the vehicle. a vehicle characteristic measuring device that measures at least one of them as a vehicle running characteristic; a tire grounding characteristic measured by the tire grounding characteristic measuring device; and the vehicle running characteristic of the vehicle measured by the vehicle characteristic measuring device. and a vehicle behavior simulation device that predicts the behavior of the vehicle when the vehicle is running based on the vehicle behavior.

Further, the method for measuring tire ground contact characteristics according to one aspect of the present invention includes a drum driving step of rotating a rotating drum around a rotation axis, and a drum driving step that is embedded in a cylindrical surface of the rotating drum and applied to a tire that is in contact with the cylindrical surface. A sensor array for measuring stress, the sensor array having a plurality of stress measurement regions arranged in tandem in the direction of the rotational axis of the cylindrical surface and capable of independently measuring stress, is mounted on the rotating circumference of the rotating drum. A stress measuring means is provided at different positions in a plurality of stress measuring means, and the stress measuring regions of the plurality of sensor rows are arranged at different positions in the rotation axis direction among the plurality of sensor rows. a stress measuring step of measuring the stress measured by the at least two sensor rows among the stresses measured by the stress measuring step; a processing step of calculating a tire ground contact characteristic which is a characteristic in the region; an output step of outputting the tire ground contact characteristic calculated by the processing step ; and a step of interpolating the stress measured by the stress measurement region provided in the sensor array. and an interpolation step of calculating as post-stress information, the resolution of stress in the post-interpolated stress information is higher than the resolution of stress measured by the stress measurement area, and the processing step includes a step of calculating stress resolution in the post-interpolated stress information. Tire ground contact characteristics, which are characteristics of the ground contact area of the tread surface of the tire that contacts the rotating drum, are calculated based on the synthesized stress with higher resolution .

According to the present invention, it is possible to provide a tire ground contact characteristic measuring device, a tire ground contact characteristic measuring system, and a tire ground contact characteristic measuring method that can increase the resolution in the rotation axis direction.

1 shows an example of the configuration of a tire ground contact characteristic measuring system in an embodiment. FIG. 2 is a diagram for explaining a tire and a rotating drum of a tire ground contact characteristic measuring device in an embodiment. FIG. 2 is a diagram for explaining a ground contact area that contacts a rotating drum on the tread surface of a tire in an embodiment. It is a diagram showing the functional configuration of a processing device in an embodiment. It is a figure showing an example of composition of the 1st stress measuring means and the 2nd stress measuring means in an embodiment. It is a figure showing an example of arrangement of the 1st stress measuring means and the 2nd stress measuring means in an embodiment. FIG. 3 is a diagram for explaining the ground contact characteristics of a synthetic tire in an embodiment. It is a figure which shows the stress distribution based on the stress measured by the 1st stress measurement means in embodiment, and the stress distribution based on the stress measured by the 2nd stress measurement means. It is a figure which shows the stress distribution which a synthesis part produces|generates based on the stress measured by the 1st stress measurement means and the stress measured by the 2nd stress measurement means in embodiment. It is a figure which shows the modification of the functional structure of the processing apparatus in embodiment. FIG. 3 is a diagram for explaining the synthetic tire ground contact characteristics when linear interpolation is performed in the embodiment. FIG. 6 is a diagram showing a stress distribution when the stress measured by the first stress measuring means in the embodiment is linearly interpolated, and a stress distribution when the stress measured by the second stress measuring means is linearly interpolated. It is a figure which shows the stress distribution based on the synthetic tire ground contact characteristic when linear interpolation is performed in embodiment.

Embodiments of the present invention will be described below with reference to the drawings.
[Configuration of tire ground contact characteristic measurement system 400]
An example of a tire ground contact characteristic measurement system 400 according to an embodiment will be described with reference to FIGS. 1 to 3.
FIG. 1 is a diagram showing an example of the configuration of a tire ground contact characteristic measurement system 400 in an embodiment. As shown in the figure, the tire ground contact characteristic measurement system 400 can include a tire ground contact characteristic measurement device 100, a vehicle characteristic measurement device 200, and a vehicle behavior simulation device 300.

[Configuration of tire ground contact characteristic measuring device 100]
The tire ground contact characteristic measuring device 100 measures the ground contact characteristics of the tire T (hereinafter referred to as tire ground contact characteristics). The tire ground contact characteristics indicate the characteristics of the tire T in the ground contact area. Specifically, tire ground characteristics include measured values obtained from various sensors, various stresses calculated from the measured values, wear energy, amount of slip, ground force distribution, widthwise shear stress distribution, and circumferential direction shear stress distribution. It shows characteristics such as

The tire ground contact characteristic measuring device 100 includes a rotating drum 1, a drum drive means 2, a stress measurement means 3, a processing device 4, an output device 4A, a tire position control means 5, a tire drive means 6, It includes a tire angle control means 7, a drum side rotational position detection means 8, a tire side rotational position detection means 9, and a tire air pressure change means 10.

The rotating drum 1 is a generally cylindrical drum configured to be rotatable. In this example, the rotating drum 1 is a cylindrical drum rotatable around a rotation axis.

The drum driving means 2 drives the rotating drum 1 to rotate around the rotation axis. Specifically, the drum driving means 2 includes a motor and the like. The drum driving means 2 includes a drum shaft 2A. The drum shaft 2A is connected to the rotating drum 1. The drum drive means 2 can drive the rotary drum 1 to rotate in either forward or reverse directions around the rotation axis. Further, the drum driving means 2 can adjust the rotation speed of the rotating drum 1.
In this embodiment, the rotating drum 1 will be described as an outside drum type, but the rotating drum 1 may be an inside drum type. Hereinafter, the drum driving means 2 will also be referred to as drum driving means.

The stress measuring means 3 is embedded in the cylindrical surface 1A of the rotating drum 1 and measures the stress (tire force) applied to the tire T in contact with the rotating drum 1. The stress measuring means 3 can be configured to include, for example, a three-component force sensor capable of measuring ground force, width direction shear stress, and circumferential direction shear stress applied to the tire T. In this example, the stress measuring means 3 will be explained as including a three-component force sensor, but the stress measuring means 3 includes a sensor that measures ground force, and two sensors that measure widthwise shear stress and circumferential shear stress. It may also be combined with an axis sensor.

The stress measuring means 3 includes a plurality of sensor rows.
The sensor array is embedded in the cylindrical surface 1A of the rotating drum 1 and measures the stress applied to the tire T that comes into contact with the cylindrical surface 1A. The sensor array is arranged in tandem in the direction of the rotation axis of the cylindrical surface 1A, and has a plurality of stress measurement regions that can independently measure stress.
The stress measuring means 3 includes a plurality of sensor rows at different positions in the circumferential direction of the rotating drum 1.
The first stress measuring means 3A and the second stress measuring means 3B are an example of a sensor array.

The processing device 4 calculates tire ground contact characteristics based on the stress measured by the first stress measuring means 3A and the stress measured by the second stress measuring means 3B.
The processing device 4 is, for example, a microcomputer equipped with a CPU (central processing unit), memory, and the like. A data analysis program for analyzing measurement results is stored in the memory of the processing device 4. As the data analysis program, for example, a general-purpose numerical analysis program is used.
The processing device 4 is connected to an output device 4A. The processing device 4 provides the calculated tire ground contact characteristics to the output device 4A.

The output device 4A outputs the tire ground contact characteristics calculated by the processing device 4. The output device 4A includes, for example, a liquid crystal display surface, and displays information including tire ground contact characteristics based on the information output by the processing device 4. In this example, the output device 4A will be described as a monitor equipped with a liquid crystal display screen.
The information output by the output device 4A broadly includes information obtained by visualizing information calculated by other processing devices 4. For example, the information output by the output device 4A may be information obtained by visualizing the ground force distribution, width direction shear stress distribution, circumferential direction shear stress distribution, etc. calculated by the processing device 4.
Note that in this example, the output device 4A will be described as an image display device, but the present invention is not limited to this example, and the output device 4A may be configured as an information output device such as a printer device.

The tire position control means 5 controls the position of the tire T with respect to the rotating drum 1. Specifically, the tire position control means 5 is capable of adjusting the position of the tire T with respect to the rotary drum 1 in the direction of the rotation axis of the rotary drum 1 and/or in the radial direction.
In this example, the tire position control means 5 adjusts the position of the tire T with respect to the rotary drum 1 by controlling the position of the tire T, but the position of the rotary drum 1 with respect to the tire T may be controlled. Furthermore, the position of the rotary drum 1 with respect to the tire T may be controlled by controlling both the position of the tire T and the position of the rotary drum 1.
The tire position control means 5 includes a spindle shaft 5A connected to the tire T, a tire drive means 6, and a tire angle control means 7.

The tire drive means 6 drives the tire T to rotate. In this example, the tire drive means 6 includes a motor or the like. The tire drive means 6 can rotate the tire T around the rotation axis in either forward or reverse directions. Further, the tire drive means 6 can adjust the rotational speed of the tire T.
The spindle shaft 5A transmits the power of the tire drive means 6 to the tire T.

The tire angle control means 7 controls the angle of the tire T with respect to the rotating drum 1. Specifically, the tire angle control means 7 can give the tire T a camber angle CA. Further, the tire angle control means 7 can apply a slip angle SA to the tire T. Further, the tire angle control means 7 can apply ground contact force to the tire T by bringing the tire T into contact with the rotating drum 1. In other words, the tire angle control means 7 can reproduce the tire attitude of the actual vehicle during cornering, etc. on the tire T by adjusting at least one of the camber angle CA, slip angle SA, and ground contact force of the tire T. .
Either or both of the camber angle CA and the slip angle SA given to the tire T can also be adjusted to 0°. When both the camber angle CA and the slip angle SA given to the tire T are adjusted to 0°, the tire attitude when the actual vehicle is traveling straight is reproduced on the tire T.

The drum-side rotational position detection means 8 detects the rotational position of the rotating drum 1. Specifically, the drum-side rotational position detection means 8 detects the rotational position of the stress measurement means 3 embedded in the cylindrical surface 1A of the rotary drum 1.
The drum-side rotational position detection means 8 is, for example, a rotary encoder arranged on the drum shaft 2A of the drum drive means 2.

The tire-side rotational position detection means 9 detects the rotational position of the tire T. Specifically, the tire-side rotational position detection means 9 detects the rotational position of the tire T with respect to the reference position.
The tire-side rotational position detection means 9 is, for example, a rotary encoder arranged on the spindle shaft 5A of the tire position control means 5.

The tire air pressure changing means 10 changes the air pressure of the tire T. The tire pressure changing means 10 has a function of changing the air pressure of the tire T, for example, during a period when the tire angle control means 7 is changing at least one of the camber angle, slip angle, and ground contact force of the tire T. have
The tire ground contact characteristic measuring device 100 can predict and understand the behavior when a so-called puncture occurs by changing the air pressure of the tire T by the tire air pressure changing means 10.

[Configuration of vehicle characteristic measuring device 200]
The vehicle characteristic measuring device 200 includes a test vehicle 201 having a vehicle body 203, wheels 202, and a steering wheel 205, a mount device (suspension characteristic measuring device) 210, and a controller (computer) 220.
The gantry device 210 includes a support section 214 and a measuring device 215.

The test vehicle 201 is placed on the support portion 214 . In this example, the support portion 214 can independently displace the vehicle body 203 and the wheels 202. Specifically, the support portion 214 independently displaces the vehicle body 203 and the wheels 202 in the longitudinal direction, left-right direction, vertical direction, pitch direction, and roll direction of the test vehicle 201.
Note that the support portion 214 is slidable relative to the wheel 202 so as to generate longitudinal force, lateral force, cornering force, slip ratio, and slip angle that may be generated in the tire while the vehicle is running. Good too.

The measuring device 215 measures at least one of the displacement amount and the acting force of the vehicle body 203 and at least one of the displacement amount and the acting force of the wheel 202. Specifically, the measuring device 215 measures the force acting on the support portion 214 . Furthermore, the measuring device 215 measures the camber angle, toe angle, steering angle, etc. of the wheels 202. The measuring device 215 also measures force or torque acting on an axle (not shown). Further, the measuring device 215 measures the stroke and acting force of the suspension.
Hereinafter, when at least one of the displacement amount and acting force of the vehicle body 203 measured by the measuring device 215 and at least one of the displacement amount and acting force of the wheels 202 are not distinguished, they will be referred to as vehicle running characteristics.

The controller 220 controls the amount of displacement applied to the vehicle body 203 by the support part 214 and the amount of displacement applied to the wheel 202 by the support part 214.

In this example, test vehicle 201 controls the steering angle of wheels 202 by driving steering wheel 205 . However, the test vehicle 201 is not limited to this example, and may be configured to not include the steering wheel 205 and to control the steering angle of the wheels 202.

[Configuration of vehicle behavior simulation device 300]
The vehicle behavior simulation device 300 predicts the behavior of an actual vehicle when it is running based on information input by an operator. Specifically, the vehicle behavior simulation device 300 calculates the vehicle characteristics predicted from the tire contact characteristics calculated by the processing device 4 of the tire contact characteristics measurement device 100 and the vehicle characteristics predicted by the tire contact characteristics calculated by the processing device 4 of the tire contact characteristics measurement device 100 and the vehicle characteristics measured by the measuring device 215 of the vehicle characteristic measurement device 200. At least one of the displacement amount and the acting force of the vehicle body 203 and at least one of the displacement amount and the acting force of the wheels 202 (vehicle running characteristics) are reflected in the vehicle model in the vehicle behavior simulation device 300, and the driving time of the actual vehicle is reflected. Predict the behavior of
The vehicle characteristics may include various parameters such as vehicle position, steering angle, pitch axis, roll axis, moment around the yaw axis, vehicle speed, vehicle inertia parameter, ground force, tire axial force, etc. The axial force of the tire can include at least six components of force acting on the rotation axis of the tire. The 6-component force is the force acting on the fixed axis of the tire along the X-axis, Y-axis, and Z-axis, the moment acting around the X-axis, the moment acting around the Y-axis, and the moment acting around the Z-axis. Point.
Further, commands based on predicted vehicle characteristics can be transmitted to an on-vehicle electronic control unit. The command may include wheel speed, yaw rate, vehicle acceleration, on-axis acceleration of tires, and simulated signals in place of various on-vehicle sensors such as a forward radar and a camera.

The vehicle behavior simulation device 300 is a computer that simulates the behavior of an actual vehicle during driving, and includes a CPU as a calculation processing means, a ROM, RAM, and HDD as a storage means, and an interface as a communication means. It operates based on the program. Note that the vehicle behavior simulation device 300 may be used in combination with the processing device 4.

Further, the vehicle behavior simulation device 300 includes input means such as a keyboard and mouse, and display means such as a monitor. Note that the input means may be a device capable of reproducing the driving state, which includes a steering wheel, an accelerator, a brake, and the like.
The input means is operated by an operator. The input means is operated by a worker to obtain information such as parameters necessary for predicting the behavior of the actual vehicle when it is running.
The display means displays the estimated behavior of the actual vehicle during driving. For example, the display means displays using a vehicle model.

FIG. 2 is a diagram for explaining the tire T and the rotating drum 1 of the tire ground contact characteristic measuring device 100 in the embodiment. As shown in the figure, the tread surface T1 of the tire T is brought into contact with the cylindrical surface 1A of the rotating drum 1.

The tire drive means 6 rotates the tire T via the spindle shaft 5A. The tire drive means 6 controls the angle of the tire T with respect to the rotating drum 1 by means of a tire angle control means 7. In this example, the tire T is in contact with the rotating drum 1 while being given a camber angle CA.

The drum driving means 2 drives the rotating drum 1 via the drum shaft 2A. The stress measuring means 3 provided on the cylindrical surface 1A of the rotating drum 1 measures stress by coming into contact with the tire T.
In this example, the stress measuring means 3 contacts the tire T once every rotation of the rotating drum 1. The stress measuring means 3 measures stress every time it comes into contact with the tire T. In this example, since the first stress measuring means 3A and the second stress measuring means 3B are included in the stress measuring means 3, the first stress measuring means 3A and the second stress measuring means 3B are In each case, the stress of the tire T is measured once.

FIG. 3 is a diagram for explaining the ground contact area T1A that contacts the rotating drum 1 of the tread surface T1 of the tire T in the embodiment.
In the figure, a ground contact area of the tread surface T1 of the tire T that contacts the rotating drum 1 is shown as a ground contact area T1A. The position directly under the load where the rotating drum 1 and the tire T contact is set to a reference position B. The drum-side rotational position detection means 8 detects the rotational positions of the first stress measurement means 3A and the second stress measurement means 3B with respect to the reference position B. In this example, the drum-side rotational position detection means 8 detects the rotational position of the reference position B with respect to the first stress measurement means 3A and the rotational position of the reference position B with respect to the second stress measurement means 3B.

The rotational position of the first stress measuring means 3A with respect to the reference position B detected by the drum side rotational position detection means 8, the rotational position of the second stress measurement means 3B, and the reference position detected by the tire side rotational position detection means 9. The rotational position of the tire T with respect to B is input to the processing device 4. The processing device 4 calculates the circumferential position of the tire T in contact with the stress measuring means 3 based on the rotational position of the stress measuring means 3 with respect to the reference position B and the rotational position of the tire T with respect to the reference position B.

Based on the stress measured by the stress measuring means 3, the processing device 4 calculates tire ground contact characteristics, which are the characteristics in the ground contact area T1A of the tread surface T1 of the tire T that contacts the rotating drum 1.

The output device 4A outputs information including the tire ground contact characteristics calculated by the processing device 4. Specifically, since the output device 4A in this embodiment is a monitor equipped with a liquid crystal display screen, it displays information obtained by visualizing the ground force distribution, width direction shear stress distribution, circumferential direction shear stress distribution, etc. of the ground contact area T1A. do.

FIG. 4 is a diagram showing the functional configuration of the processing device 4 in the embodiment. The functional configuration of the processing device 4 will be explained using the same figure.
[Functional configuration of processing device 4]
The processing device 4 includes a first stress synthesis section 41, a second stress synthesis section 42, a synthesis section 43, and an output section 44. The processing device 4 acquires first stress information SD1, which is information including stress measured by the first stress measuring means 3A, from the first stress measuring means 3A. The processing device 4 acquires second stress information SD2, which is information including stress measured by the second stress measuring means 3B, from the second stress measuring means 3B. The processing device 4 acquires drum rotational position information DRP containing information indicating the rotational position of the rotary drum 1 from the drum side rotational position detection means 8 . The processing device 4 acquires tire rotational position information TRP including information indicating the rotational position of the tire T from the tire side rotational position detection means 9 .
The processing device 4 outputs stress distribution information SDD including information indicating the stress distribution in the ground contact area T1A of the tire T to the output device 4A.

The first stress synthesis section 41 acquires first stress information SD1 from the first stress measuring means 3A, acquires drum rotational position information DRP from the drum side rotational position detection means 8, and acquires the drum rotational position information DRP from the tire side rotational position detection means 9. Obtain rotational position information TRP.
The first stress synthesis unit 41 synthesizes the stresses during the period in which the first stress measuring means 3A is in contact with the ground contact region T1A, and generates first stress distribution information SDD1. The first stress synthesis section 41 provides the generated first stress distribution information SDD1 to the synthesis section 43.

The second stress synthesis unit 42 acquires second stress information SD2 from the second stress measuring means 3B, acquires drum rotational position information DRP from the drum side rotational position detection means 8, and acquires the drum rotational position information DRP from the tire side rotational position detection means 9. Obtain rotational position information TRP.
The second stress synthesis section 42 synthesizes the stresses during the period when the second stress measurement means 3B is in contact with the ground contact region T1A, and generates second stress distribution information SDD2. The second stress synthesis section 42 provides the generated second stress distribution information SDD2 to the synthesis section 43.

Note that the first stress synthesis section 41 and the second stress synthesis section 42 are configured such that the stress measurement means 3 is placed at the same position in the ground contact area T1A of the tire T under the same conditions such as the posture and speed of the tire T during measurement. When a plurality of measurement results are obtained for the same position on the tire T by facing the tire T, it is preferable to use the average of those measurement results as the measurement result.
Furthermore, by synchronizing and measuring the rotational position of the rotary drum 1 and the rotational position of the tire T by the drum-side rotational position detection means 8 and the tire-side rotational position detection means 9, tire footprint measurement with patterns (such as lug grooves, etc.) is performed. (calculation of the tire ground contact characteristics of the ground contact area T1A) can also be expressed.

The synthesizing unit 43 calculates a synthetic tire ground contact characteristic based on the stress measured by the first stress measuring means 3A and the stress measured by the second stress measuring means 3B.
The synthesis unit 43 acquires first stress distribution information SDD1 from the first stress synthesis unit 41 and second stress distribution information SDD2 from the second stress synthesis unit 42. The synthesizing unit 43 synthesizes the first stress distribution information SDD1 and the second stress distribution information SDD2 to generate synthetic tire ground contact characteristics. Hereinafter, the synthetic tire ground contact characteristics will also be referred to as stress distribution information SDD.
Specifically, the stress distribution information SDD is distribution information with higher resolution than the first stress distribution information SDD1 and the second stress distribution information SDD2. The second stress measuring means 3B is buried in a position different from the position where the first stress measuring means 3A is buried in the cylindrical surface 1A of the rotary drum 1 in the rotating circumferential direction of the rotary drum 1. is achieved by using the first stress distribution information SDD1 indicating the stress distribution measured by the first stress measuring means 3A and the second stress distribution information SDD2 indicating the stress distribution measured by the second stress measuring means 3B. , it is possible to generate stress distribution information SDD with high resolution.
The synthesis unit 43 provides the generated stress distribution information SDD to the output unit 44.
Note that the processing performed by the first stress synthesis section 41 and the second stress synthesis section 42 can be performed in the synthesis section 43 all at once.

The output unit 44 acquires stress distribution information SDD from the synthesis unit 43. The output unit 44 outputs the acquired stress distribution information SDD to the output device 4A.

FIGS. 5 to 7 are diagrams illustrating a method when the synthesis unit 43 synthesizes the stress distribution information SDD. Combining the first stress distribution information SDD1 and the second stress distribution information SDD2 will be explained using FIGS. 5 to 7.
[About combining the first stress distribution information SDD1 and the second stress distribution information SDD2]
FIG. 5 is a diagram showing the configuration of the first stress measuring means and the second stress measuring means in the embodiment. In the figure, the arrangement of the first stress measuring means 3A and the second stress measuring means 3B is shown by a two-dimensional orthogonal coordinate system of the x-axis and the y-axis. The x-axis is the direction of the rotation axis of the rotary drum 1. The y-axis is the circumferential direction in which the rotating drum 1 rotates.

The stress measuring means 3 is provided on the cylindrical surface 1A of the rotating drum 1. The stress measuring means 3 includes a sensor array (in this example, a first stress measuring means 3A and a second stress measuring means 3B). Each of the plurality of sensor rows has a stress measurement area. The respective stress measurement regions of the plurality of sensor rows are arranged at different positions in the direction of the rotation axis of the rotary drum 1 among the plurality of sensor rows.
Specifically, the first stress measuring means 3A includes a plurality of stress measuring regions 3AN arranged in a line. In the figure, the stress measurement area 3AN includes a stress measurement area 3A1, a stress measurement area 3A2, a stress measurement area 3A3, a stress measurement area 3A4,..., a stress measurement area 3A99, and a stress measurement area 3A100. be able to. The stress measurement areas 3AN can be arranged in tandem in the direction of the rotation axis of the cylindrical surface 1A (that is, the x-axis direction in the figure). The stress measuring means 3 can simplify the calculation of the rotation angle of the tire and drum by arranging the stress measuring means in tandem.
Moreover, the stress measurement areas 3AN are sensors that can each independently measure stress. In this example, the stress measurement area 3AN is a three-component force sensor that can independently measure stress, so it can independently measure the ground force applied to the tire T, the width direction shear stress, and the circumferential direction shear stress. can be measured.

The second stress measuring means 3B includes a plurality of stress measuring regions 3BN arranged in a line. In the figure, the stress measurement area 3BN includes a stress measurement area 3B1, a stress measurement area 3B2, a stress measurement area 3B3, a stress measurement area 3B4,..., a stress measurement area 3B99, and a stress measurement area 3B100. be able to. That is, in this example, the second stress measuring means 3B includes 100 stress measuring regions 3BN. The stress measurement regions 3BN can be arranged in tandem in the direction of the rotation axis of the cylindrical surface 1A (that is, the x-axis direction in the figure). By arranging the stress measuring means in tandem, calculation of the rotation angle of the tire and drum can be simplified.
The stress measurement regions 3BN are sensors that can each independently measure stress. In this example, the stress measurement area 3BN is a three-component force sensor that can independently measure stress, so it can independently measure the ground force applied to the tire T, the width direction shear stress, and the circumferential direction shear stress. can be measured.

FIG. 6 is a diagram showing an example of the arrangement of the first stress measuring means 3A and the second stress measuring means 3B in the embodiment. In the figure, the arrangement of the first stress measuring means 3A and the second stress measuring means 3B is shown by a two-dimensional orthogonal coordinate system of the x-axis and the y-axis. The x-axis is the direction of the rotation axis of the rotating drum 1. The y-axis is the circumferential direction in which the rotating drum 1 rotates.
The size of the stress measurement area 3AN and the stress measurement area 3BN, and the positional relationship between the stress measurement area 3AN and the stress measurement area 3BN will be explained using the stress measurement area 3A1 and the stress measurement area 3B1.
The length of the stress measurement region 3A1 in the y-axis direction is denoted by L11, and the length in the x-axis direction is denoted by L12. In this example, assume that L11 and L12 are of equal length.
Here, the lengths of L11 and L12 can be 2 to 8 mm (millimeters).

The stress measurement regions 3BN are arranged at different positions in the x-axis direction between the stress measurement regions 3AN and the stress measurement regions 3AN adjacent thereto. For example, the stress measurement area 3B1 is located between the stress measurement area 3A1 and the stress measurement area 3A2 adjacent thereto. The distance in the x-axis direction between the stress measurement region 3A1 located at the end of the stress measurement region 3AN and the stress measurement region 3B1 located at the end of the stress measurement region 3BN is denoted by L13. In this example, the code L13 is 1/2×L12. That is, the stress measurement regions 3AN and the stress measurement regions 3BN are arranged alternately at intervals of 1/2×L12 in the x-axis direction. If there are n rows of stress measuring means, by arranging them at intervals of 1/n x L12, the sensor centers can be arranged at equal intervals, so that the resolution can be appropriately improved. .

The stress measurement area 3AN and the stress measurement area 3BN are placed apart from each other by a certain distance. The distance between the stress measurement area 3AN and the stress measurement area 3BN is denoted by L14. In this example, it is preferable that the symbol L14 be smaller in terms of ease of installation. However, in each stress measurement area, it is possible to specify the rotational position of the tire and drum and synthesize the stress distribution, so it is not necessary to place stress measurement means at adjacent positions (positions where L14 is small). You can.

FIG. 7 is a diagram for explaining the synthetic tire ground contact characteristics in the embodiment. In the same figure, the combining unit 43 combines the stress measurement areas 3AN of the first stress measurement means 3A as the "first column" and the stress measurement areas 3BN of the second stress measurement means 3B as the "second column". Areas of stress are shown as "bonds".
As described above, in this example, the length of the stress measurement area 3AN and the stress measurement area 3BN in the x-axis direction is L12. Since the first stress measuring means 3A includes N stress measuring regions 3AN, it can measure stress in a range of L12×N in the width direction of the drum (symbol L21). Similarly, since the second stress measuring means 3B includes N stress measuring regions 3BN, it is possible to measure stress in a range of L12×N in the width direction of the drum (symbol L22).

The synthesizing unit 43 calculates a synthetic tire ground contact characteristic based on the stress measured by at least two sensor rows among the sensor rows. Specifically, the synthesizing unit 43 synthesizes the stress distribution based on the stress measured by the first stress measuring means 3A and the stress distribution based on the stress measured by the second stress measuring means 3B, and generates stress with higher resolution. Calculate the distribution. In this example, the synthesis unit 43 can calculate a stress distribution with twice the resolution of the stress distribution based on the stress measured by the first stress measurement means 3A and the second stress measurement means 3B.

Specifically, the stress area synthesized by the combining unit 43 in "coupling" is the stress measured at intervals of L12 by the stress measuring area 3AN of the first stress measuring means 3A in the "first column" and the stress in the "second column". The stress measurement area 3BN of the second stress measurement means 3B in the "eye" is generated by arranging the stresses measured at intervals of L12 at intervals of 1/2×L12.
For example, the stress measured by the stress measurement area 3A1 in the "first row" is set as the stress measurement area 3CA1 in the "coupling", and the stress measured by the stress measurement area 3B1 in the "second row" is set as the stress measurement area 3CB1 in the "coupling". The stress measured by the stress measurement area 3A2 in the "first row" is defined as the stress measurement area 3CA2 in the "coupling", and the stress measured by the stress measurement area 3B2 in the "second column" is defined as the stress measurement area 3CB2 in the "coupling". shall be.
In this way, the combining unit 43 alternately arranges the stresses measured by the stress measurement area 3AN at L12 intervals and the stresses measured by the stress measurement area 3BN at L12 intervals at 1/2×L12 intervals. Accordingly, a stress distribution with a resolution of 1/2×L12 intervals can be calculated. In this example, the range of the stress distribution generated by the synthesis unit 43 is L12×N (symbol L23).

In this example, the stress region synthesized by the synthesizing section 43 in "coupling" does not include information that straddles the boundary between the stress measurement region 3AN and the stress measurement region 3BN. Specifically, the stress at the boundary between the stress measurement area 3A1 and the stress measurement area 3A2 is measured by the stress measurement area 3B1. Therefore, the stress distribution in this embodiment can be calculated using information close to the center of the sensor.

FIG. 8 is a diagram showing a stress distribution based on the stress measured by the first stress measuring means 3A and a stress distribution based on the stress measured by the second stress measuring means 3B in the embodiment. FIG. 8(A) is a diagram showing the stress distribution based on the stress measured by the first stress measuring means 3A. FIG. 8(B) is a diagram showing the stress distribution based on the stress measured by the second stress measuring means 3B.
Specifically, FIG. 8(A) shows first stress distribution information generated by the first stress synthesis unit 41 based on the first stress information SD1, the drum rotational position information DRP, and the tire rotational position information TRP. This is an example of tire ground contact characteristics obtained by visualizing SDD1. FIG. 8(B) shows the second stress distribution information SDD2 generated by the second stress synthesis unit 42 based on the second stress information SD2, the drum rotational position information DRP, and the tire rotational position information TRP. This is an example of tire ground contact characteristics.

The horizontal axis in FIGS. 8(A) and 8(B) indicates the width direction of the tire T, and the vertical axis in FIGS. 8(A) and 8(B) indicates the circumferential direction of the tire T. The upper side of FIGS. 8(A) and 8(B) shows the stepping side of the tire T, and the lower side of FIGS. 8(A) and 8(B) shows the kicking side of the tire T.
In the example shown in FIGS. 8(A) and 8(B), the distribution is based on the stress obtained by the first stress measuring means 3A and the second stress measuring means 3B at intervals of L12. That is, the resolution in the figure is L12 intervals.

FIG. 9 is a diagram showing the stress distribution generated by the combining section 43 based on the stress measured by the first stress measuring means 3A and the stress measured by the second stress measuring means 3B in the embodiment.
Specifically, FIG. 9 is an example of tire ground contact characteristics obtained by visualizing the stress distribution information SDD generated by the synthesis unit 43 based on the first stress distribution information SDD1 and the second stress distribution information SDD2.

The horizontal axis in FIG. 9 indicates the width direction of the tire T, and the vertical axis in FIG. 9 indicates the circumferential direction of the tire T. The upper side of FIG. 9 shows the kicking side of the tire T, and the lower side of FIG. 9 shows the stepping side of the tire T.
In the example shown in FIG. 9, the stress distribution is a combination of the stress obtained by the first stress measurement means 3A at L12 intervals and the stress obtained by the second stress measurement means 3B at L12 intervals, so The resolution is 1/2×L12 intervals.

FIG. 10 is a diagram showing a modified example of the functional configuration of the processing device 4 in the embodiment.
[Modified example of functional configuration of processing device 4]
The functional configuration of the processing device 40 will be explained using the same figure. The processing device 40 is a modification of the processing device 4. Components similar to those of the processing device 4 described above are denoted by the same reference numerals, and the description thereof will be omitted. The processing device 40 differs from the processing device 4 in that it includes a first interpolation section 45 and a second interpolation section 46.
Referring to the figure, the processing device 40 includes the first interpolation section 45 and the second interpolation section 46, so that the stress obtained from each stress measurement means (the first stress measurement means 3A and the second stress measurement means 3B) is We will explain the case of interpolating the calculated stress and synthesizing the interpolated data. Note that the number of stress measuring means is not limited to this example, and a plurality of stress measuring means may be provided. If the number of stress measurement means increases, it is possible to perform interpolation processing on the combined results all at once, but it is also possible to increase the number of points and data points that allow you to understand the situation of each stress measurement means and average them. In some cases, it is preferable to use data obtained by directly interpolating the stress obtained from each measurement means.

The first interpolation section 45 acquires first stress information SD1, which is the stress measured by the stress measurement area 3AN included in the first stress measurement means 3A, from the first stress measurement means 3A. The first interpolation unit 45 calculates the acquired first stress information SD1 by interpolation as post-interpolated first stress information SD1A. In this example, the interpolation performed by the first interpolation unit 45 may be linear interpolation or polynomial interpolation using a predetermined polynomial.
The first interpolator 45 provides the first stress information SD1A after interpolation to the first stress synthesizer 41.

The second interpolation unit 46 acquires second stress information SD2, which is the stress measured by the stress measurement region 3BN included in the second stress measurement means 3B, from the second stress measurement means 3B. The second interpolation unit 46 calculates the acquired second stress information SD2 by interpolation as post-interpolated second stress information SD2A. In this example, the interpolation performed by the second interpolation unit 46 may be linear interpolation or spline interpolation.
The second interpolation unit 46 provides the second stress synthesis unit 42 with the interpolated second stress information SD2A.

Note that when the first interpolation section 45 and the second interpolation section 46 are not distinguished, they are also referred to as an interpolation section. The interpolation performed by the interpolation unit is not limited to linear interpolation and polynomial interpolation. For example, the interpolation performed by the first interpolation unit 45 may be polynomial interpolation or the like.
When linear interpolation, polynomial interpolation, and spline interpolation are not distinguished, they may be referred to as interpolation.

FIG. 11 is a diagram for explaining the synthetic tire ground contact characteristics when linear interpolation is performed in the embodiment. In the figure, the stress measurement area 3AN provided in the first stress measurement means 3A is defined as the "first column", and the stress area after interpolation by the first interpolation unit 45 is defined as the "first column linear interpolation (1/2×L12 The stress measurement area 3BN provided in the second stress measurement means 3B is set as the "second column", and the stress area after interpolation by the second interpolation unit 46 is determined by "second column linear interpolation (1/2× The region of stress synthesized by the synthesizing section 43 is shown as a "coupling".
By interpolating so that the number is multiplied by n times the ground contact points of the stress measuring means, it is possible to easily interpolate and synthesize information from a plurality of stress measuring means. That is, it is desirable to perform interpolation such that the measurement area is 1/(grounding point of the stress measuring means x n). In the embodiment described later, since there are two stress measurement locations, an example in which interpolation such as 2×2 is performed will be exemplified.

The first interpolation unit 45 applies linear interpolation to the stress measured at L12 intervals by the stress measurement area 3AN of the first stress measurement means 3A, and calculates the stress at 1/4×L12 intervals. “First column linear interpolation” shown in the same figure indicates stress generated by the first interpolation unit 45 at intervals of 1/4×L12.
The second interpolation unit 46 applies linear interpolation to the stress measured at L12 intervals by the stress measurement area 3AB of the second stress measurement means 3B, and calculates the stress at 1/4×L12 intervals. “Second column linear interpolation” shown in the same figure indicates stress generated by the second interpolation unit 46 at intervals of 1/4×L12.

The synthesizing unit 43 generates first stress distribution information SDD1 based on stress at intervals of 1/4×L12 calculated by the first interpolation unit 45 and first stress distribution information SDD1 based on stress at intervals of 1/4×L12 calculated by the second interpolation unit 46. 2. Based on the stress distribution information SDD2, interpolation processing is performed to perform interpolation in the direction of the rotation axis of the rotary drum 1. The synthesis unit 43 calculates a synthetic tire ground contact characteristic with higher resolution by performing interpolation processing to synthesize the first stress distribution information SDD1 and the second stress distribution information SDD2.
In this example, the synthesis unit 43 can calculate a stress distribution with four times the resolution of the stress distribution based on the stress measured by the first stress measurement means 3A and the second stress measurement means 3B.

Specifically, the stress area synthesized by the synthesis unit 43 in “coupling” is the stress based on the stress at 1/4×L12 interval calculated by the first interpolation unit 45 in “first column linear interpolation”, and “ Regarding the portion where the stress of 1/4×L12 interval calculated by the second interpolation unit 46 in "second row linear interpolation" overlaps in the circumferential direction of the rotating drum 1 (range indicated by code L33), the first interpolation The average value of the stress at intervals of 1/4×L12 calculated by the unit 45 and the stress at intervals of 1/4×L12 calculated by the second interpolation unit 46 is used.
For example, the stress measurement area 3C1C uses the average value of the stress measurement area 3A1C and the stress measurement area 3B1A. The same applies to stress measurement areas 3C1C to 3C100C.

Since the first stress measuring means 3A and the second stress measuring means 3B are arranged shifted by 1/2×L12 in the direction of the rotation axis of the rotary drum 1, the first interpolation section 45 in "first row linear interpolation" The stress based on the stress at the 1/4 x L12 interval calculated by , and the stress at the 1/4 x L12 interval calculated by the second interpolation unit 46 in "second row linear interpolation" overlap in the circumferential direction of the rotating drum 1. There are portions where the data is not included (ranges indicated by symbols L34 and L35). For these parts, the stress based on the stress at 1/4 x L12 intervals calculated by the first interpolation unit 45 in 1 linear interpolation in the 1st column (in 1/2 x L12 increments) or the stress based on the stress at 1/4 x L12 intervals in the 1 linear interpolation in the 2nd column The stress of either one of the 1/4×L12 intervals calculated by the second interpolation unit 46 in “(1/2×L12 increments)” can be used as is.
For example, stress measurement regions 3A1A and 3A1B can be applied to stress measurement region 3C1A and stress measurement region 3C1B, respectively, and stress measurement regions 3B100B and 3B100C can be applied to stress measurement region 3C100D and stress measurement region 3C101A, respectively. .

FIG. 12 shows the stress distribution when the stress measured by the first stress measuring means 3A in the embodiment is linearly interpolated, and the stress distribution when the stress measured by the second stress measuring means 3B is linearly interpolated. FIG. FIG. 12(A) is a diagram showing the stress distribution when the stress measured by the first stress measuring means 3A is linearly interpolated. FIG. 12(B) is a diagram showing the stress distribution when the stress measured by the second stress measuring means 3B is subjected to linear interpolation.

Specifically, FIG. 12(A) shows the first stress generated by the first stress synthesis unit 41 based on the interpolated first stress information SD1A, the drum rotational position information DRP, and the tire rotational position information TRP. This is an example of tire ground contact characteristics obtained by visualizing the distribution information SDD1. FIG. 12(B) visualizes the second stress distribution information SDD2 that the second stress synthesis unit 42 generates based on the interpolated second stress information SD2A, the drum rotational position information DRP, and the tire rotational position information TRP. This is an example of processed tire ground contact characteristics. When the first post-interpolated stress information SD1A and the second post-interpolated stress information SD2A are not distinguished, they are also referred to as post-interpolated stress information.

The horizontal axis in FIGS. 12(A) and 12(B) indicates the width direction of the tire T, and the vertical axis in FIGS. 12(A) and 12(B) indicates the circumferential direction of the tire T. The upper side of FIGS. 12(A) and 12(B) shows the stepping side of the tire T, and the lower side of FIGS. 12(A) and 12(B) shows the kicking side of the tire T.

FIG. 13 is a diagram showing the stress distribution based on the synthetic tire ground contact characteristics when linear interpolation is performed in the embodiment. Specifically, in the example shown in FIG. 13, the synthesis unit 43 generates first stress distribution information SDD1 based on the interpolated first stress information SD1A, and second stress distribution information SDD2 based on the interpolated second stress information SD2A. This is an example of synthetic tire ground contact characteristics obtained by visualizing the stress distribution information SDD generated based on the following.
In the figure, the processing device 40 has four times the resolution as compared to the case where the processing device 40 does not include the first interpolation section 45 and the second interpolation section 46 (see FIG. 8). That is, the resolution in the figure is 1/4×L12 intervals.

[Summary of effects of embodiment]
As described above, the tire ground contact characteristic measuring device 100 of this embodiment includes the first stress measuring means 3A and the second stress measuring means 3B on the cylindrical surface 1A of the rotating drum 1. The first stress measuring means 3A and the second stress measuring means 3B are arranged at different positions in the direction of the rotation axis of the rotary drum 1.
The processing device 4 calculates the tire ground contact characteristics based on the first stress measuring means 3A and the second stress measuring means 3B, which are arranged at different positions in the direction of the rotation axis of the rotary drum 1. Therefore, the tire ground contact characteristic measuring device 100 of this embodiment can increase the resolution in the rotation axis direction compared to the case where the second stress measuring means 3B is not provided.

Further, according to the embodiment described above, the first stress measuring means 3A and the second stress measuring means 3B are provided with a plurality of stress measuring regions capable of independently measuring stress. The stress measurement region 3BN of the second stress measurement means 3B is arranged between the stress measurement region 3AN of the first stress measurement means 3A and the stress measurement region 3AN adjacent thereto.
Therefore, the synthesis unit 43 can calculate a stress distribution with twice the resolution by alternately arranging the stress measured by the stress measurement area 3AN and the stress measured by the stress measurement area 3BN. In other words, the tire ground contact characteristic measuring device 100 can easily calculate a stress distribution with a resolution twice as high as the location where the stress measuring means is installed.

Further, according to the embodiment described above, the tire ground contact characteristic measuring device 100 includes the synthesis section 43, the first interpolation section 45, and the second interpolation section 46. The tire ground contact characteristic measuring device 100 includes a first interpolation section 45 and a second interpolation section 46, so that the first stress information SD1 measured by the first stress measuring means 3A and the first stress information SD1 measured by the second stress measuring means 3B are The second stress information SD2 is subjected to linear interpolation. The synthesizing unit 43 synthesizes the interpolated first stress information SD1A subjected to linear interpolation and the interpolated second stress information SD2A, thereby obtaining information about the sensors included in the first stress measuring means 3A and the second stress measuring means 3B. It is possible to calculate a stress distribution with higher resolution than a numerical value.

Further, according to the embodiment described above, the linear interpolation performed by the first interpolation section 45 and the second interpolation section 46 is linear interpolation. Therefore, the tire ground contact characteristic measuring device 100 can perform processing at high speed.

Further, according to the embodiment described above, the first stress measuring means 3A and the second stress measuring means 3B include a three-component force sensor. Therefore, the tire ground contact characteristic measuring device 100 can measure the ground contact force applied to the tire T, the width direction shear stress, and the circumferential direction shear stress.

Although the mode for implementing the present invention has been described above using embodiments, the present invention is not limited to these embodiments in any way, and various modifications and substitutions can be made without departing from the spirit of the present invention. can be added.

1... Rotating drum 2... Drum drive means 2A... Drum shaft 3... Stress measuring means 3A... First stress measuring means 3B... Second stress measuring means 4... Processing device 4A... Output device 5... Tire position control means 5A... Spindle Shaft 6... Tire drive means 7... Tire angle control means 8... Drum side rotational position detection means 9... Tire side rotational position detection means 10... Tire air pressure changing means 100... Tire ground contact characteristic measuring device 200... Vehicle characteristic measuring device 201... Test vehicle 202... Wheels 203... Vehicle body 205... Steering wheel 210... Frame device 214... Support part 215... Measuring instrument 220... Controller 300... Vehicle behavior simulation device T... Tire T1... Tread surface T1A... Ground contact area

Claims (8)

A cylindrical rotating drum that can rotate around a rotation axis,
drum driving means for rotationally driving the rotating drum around a rotation axis;
A sensor array is embedded in the cylindrical surface of the rotating drum and measures the stress applied to the tire in contact with the cylindrical surface, and is arranged in tandem in the direction of the rotational axis of the cylindrical surface and can independently measure stress. A plurality of sensor rows each having a plurality of stress measurement regions are provided at mutually different positions in the rotating circumferential direction of the rotating drum, and each of the plurality of sensor rows has a plurality of stress measurement regions each having a plurality of positions in the rotation axis direction. stress measuring means arranged at mutually different positions between the sensor rows;
Based on the stress measured by at least two of the plurality of sensor rows of the plurality of sensor rows included in the stress measuring means, tire ground contact is a characteristic of a ground contact region of the tread surface of the tire that contacts the rotating drum. a processing device that calculates the characteristics;
an output device that outputs the tire ground contact characteristics calculated by the processing device ;
an interpolation unit that calculates the stress measured by the stress measurement area of the sensor array as post-interpolated stress information by interpolation;
The stress resolution in the interpolated stress information is higher than the stress resolution measured by the stress measurement area,
The processing device determines tire ground contact characteristics, which are characteristics of a ground contact area of the tread surface of the tire that contacts the rotating drum, based on a stress with a higher resolution obtained by synthesizing stress resolutions in the interpolated stress information. calculate
Tire ground characteristics measuring device. The tire ground contact characteristic measurement device according to claim 1, wherein the processing device further includes a synthesis unit that calculates a composite tire ground contact characteristic based on the stress measured by at least two of the sensor rows. The synthesis unit calculates the synthetic tire ground contact characteristic by performing an interpolation process of interpolating in the direction of the rotation axis of the rotating drum based on the post-interpolation stress information calculated by the interpolation unit,
The tire ground contact characteristic measuring device according to claim 2, wherein the output device outputs the composite tire ground contact characteristic calculated by the synthesis section. The tire ground contact characteristic measuring device according to claim 2 or 3, wherein the interpolation is linear interpolation. The tire ground contact characteristic measuring device according to claim 2 or 3, wherein the interpolation is spline interpolation. The tire ground contact according to any one of claims 1 to 5, wherein the stress measuring means includes a three-component force sensor capable of measuring ground contact force, width direction shear stress, and circumferential direction shear stress applied to the tire. Characteristic measurement device. The tire ground contact characteristic measuring device according to any one of claims 1 to 6,
a vehicle characteristic measuring device that measures at least one of a displacement amount and an acting force of a vehicle, and at least one of a displacement amount and an acting force of wheels included in the vehicle as vehicle running characteristics;
a vehicle behavior simulation device that predicts the behavior of the vehicle during running based on the tire ground contact characteristic measured by the tire ground contact characteristic measurement device and the vehicle running characteristic of the vehicle measured by the vehicle characteristic measurement device; Equipped with a tire ground contact characteristics measurement system. a drum drive step for rotating the rotating drum around the rotation axis;
A sensor array is embedded in the cylindrical surface of the rotating drum and measures the stress applied to the tire in contact with the cylindrical surface, and is arranged in tandem in the direction of the rotational axis of the cylindrical surface and can independently measure stress. A plurality of sensor rows each having a plurality of stress measurement regions are provided at mutually different positions in the rotating circumferential direction of the rotating drum, and each of the plurality of sensor rows has a plurality of stress measurement regions each having a plurality of positions in the rotation axis direction. a stress measuring step of measuring stress of stress measuring means arranged at mutually different positions between the sensor rows;
Tire ground contact characteristics, which are characteristics in a ground contact area of the tread surface of the tire that contacts the rotating drum, based on the stresses measured by at least two of the sensor rows among the stresses measured in the stress measuring step. a processing step for calculating
an output step of outputting the tire ground contact characteristics calculated in the processing step ;
an interpolation step of calculating the stress measured by the stress measurement area of the sensor array as post-interpolated stress information by interpolation;
The stress resolution in the interpolated stress information is higher than the stress resolution measured by the stress measurement area,
The processing step determines tire ground contact characteristics, which are characteristics of a ground contact area of the tread surface of the tire that contacts the rotating drum, based on a stress with a higher resolution obtained by synthesizing stress resolutions in the post-interpolated stress information. calculate
Method for measuring tire ground contact characteristics.

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