JP4082101B2 - Chassis dynamo device and vehicle test method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a chassis dynamo device and a vehicle test method for performing a vehicle performance test.
[0002]
[Prior art]
As shown in FIG. 11, the conventional chassis dynamo device fixes the rotor shaft of the load motor 52 to the rotating shaft of the contact ring roller 53 that is rotatably supported, for example, and drives the vehicle 10 on the contact roller 53. Some wheels (front wheels in the case of front-wheel drive vehicles) 11 are placed. Then, the vehicle 10 is driven, and this driving force is absorbed by the load motor 52 via the contact roller 53, so that a mechanical load equivalent to the traveling resistance when the vehicle 10 actually travels on the road is simulated. Produced various types of tests such as fuel consumption measurement and exhaust gas measurement.
[0003]
[Problems to be solved by the invention]
In this case, the mechanical load on the drive system of the vehicle 10 is determined by the impedance value of the variable impedance element as an electrical load connected between the terminals of the load motor 52. Therefore, it can be considered that an arbitrary mechanical load is created by adjusting the impedance value.
[0004]
By the way, since the contact area between the drive wheels 11, that is, the contact area between the drive wheels 11 and the contact roller 53 greatly affects the running resistance, it is necessary to make the peripheral surface of the contact wheel 53 as flat as possible. As the ring roller 53, a roller having a large diameter such as 1100 mm or 1700 mm is used.
[0005]
However, since the large-diameter contact roller 53 generates a large inertial force due to its rotation as described above, there is a delay in following the rotation of the contact roller 53 when the electrical load is rapidly changed. The mechanical load on the vehicle 10 cannot be changed rapidly. Therefore, with the conventional chassis dynamo device, it is not possible to reproduce rapidly changing dynamic driving conditions, and quasi-static driving conditions such as constant vehicle speed, constant road surface inclination angle, and driving with a predetermined load pattern. It was mainly used for testing in Japan.
[0006]
SUMMARY OF THE INVENTION An object of the present invention is to provide means capable of performing a vehicle test under dynamic driving conditions by reproducing rapidly changing driving conditions.
[0007]
[Means for Solving the Problems]
  The first aspect of the present invention is a vehicle drive wheel.Directly connectedLoad motorAnd a contact roller that contacts the drive wheel with a peripheral surface, a compensation motor that is directly coupled to the contact wheel roller, and compensation control means that controls the motion of the compensation motor, the compensation control means comprising the load motor The inertial force of the contact roller is reduced by driving the compensation motor based on the physical quantity indicating the motion of the drive wheel obtained fromThis is a chassis dynamo device.
[0008]
  In the first aspect of the present invention, since the load motor is directly connected to the drive wheel of the vehicle, the influence of the inertial force of the contact roller is markedly greater than in the case where the load motor is coupled to the contact wheel roller as in the prior art. The vehicle can be made small, and a pseudo load with high responsiveness can be given to the vehicle.In the first aspect of the present invention, the compensation motor for driving the contact roller is driven based on a physical quantity indicating the motion of the drive wheel acquired from the load motor, so that the mechanical load applied to the vehicle by the load motor is reduced. Relations such as synchronization can be given to fluctuations and fluctuations of the inertial force of the contact roller, and a sudden change in traveling conditions can be faithfully reproduced. It is also possible to use the feedback output of the load motor for the synchronous operation of the compensation motor. It is preferable to use the speed, torque, speed change or torque change of the drive wheel as the physical quantity indicating the motion of the drive wheel.
[0009]
A second aspect of the present invention is a chassis dynamo device according to the first aspect of the present invention, comprising variable load means electrically connected to a load motor, and load control means for controlling an electric load value of the variable load means. A chassis dynamo device further provided.
[0010]
In the second aspect of the present invention, since the load control means controls the electric load value of the variable load means electrically connected to the load motor, the effect of the first aspect of the present invention can be realized with a simple configuration.
[0015]
  First3The present invention is the chassis dynamo apparatus according to the first or second aspect of the present invention, further comprising a free roller contacting a peripheral surface of the drive wheel.
[0016]
  First3According to the present invention, the apparatus further includes a free roller that is in contact with the drive wheel on its peripheral surface, that is, a roller that is supported so as to be freely rotatable and is not provided with a load means.
[0017]
  First4The present invention includes the first to the first3The chassis dynamo device according to any one of the present invention, further comprising a holding mechanism for levitating the peripheral surface of the drive wheel.
[0018]
  First4In the present invention, the influence of the driving wheel from the ground contact surface can be eliminated by floating the peripheral surface of the driving wheel by the holding mechanism.
[0019]
  First5The present invention includes the first to the first4The chassis dynamo device according to any one of the present invention,carStorage means for preliminarily storing parameters indicating test conditions relating to both and the road surface, wherein the load control means controls the electric load value of the variable load means in accordance with the parameters stored in the storage means A chassis dynamo device characterized by
[0020]
  First5In the present invention, the load control means controls the electric load value of the variable load means in accordance with the parameter indicating the test condition relating to the vehicle or the road surface, thereby realizing a mechanical load on the vehicle according to the test condition. it can.
[0021]
  First6The present invention is the first5The chassis dynamo device according to the present invention is characterized in that the load control means controls the electric load value in consideration of a measured value of a state during operation of the vehicle.
[0022]
  First6In the present invention, the measurement value relating to the state of the vehicle can be reflected in real time on the mechanical load on the vehicle, and a more faithful test can be realized.
[0023]
  First5Or second6The vehicle conditions in the present invention are as follows.7As in the present invention, the friction condition of the road surface8As in the present invention, the road surface slope or9It can be the curvature of the road surface as in the present invention.10Various physical quantities representing road surface properties, topography, and weather conditions such as outside air temperature / humidity and atmospheric pressure, such as road surface unevenness conditions as in the present invention, can be expressed as parameters. The test conditions are11It may be a condition of the vehicle itself such as a power transmission system parameter as in the present invention.
[0024]
  The test conditions are12As in the present invention, it may be acquired by an actual traveling test on a predetermined traveling route, and the vehicle conditions in the actual traveling can be accurately reproduced.
[0025]
  First13The present invention isOf the first inventionA vehicle testing method using a chassis dynamo device, the step of storing parameters indicating test conditions relating to the vehicle and the road surface, the step of measuring the state of the vehicle in operation, and the stored parameters and the measurement A vehicle test method including a step of calculating an electric load value based on a measured value and a step of controlling the electric load value of the variable load means based on the calculated electric load value.
[0026]
  First13In the present invention, since the electric load value of the variable load means is controlled based on the parameter indicating the test condition and the measured value by the measurement of the vehicle, a faithful test reflecting the state of the driving vehicle in real time is performed. realizable.
[0027]
  First14The present invention includes the first to the first6A vehicle test method using the chassis dynamo device according to any one of the present invention, wherein a vibration is applied to a drive wheel by driving a load motor.
[0028]
  First14In the present invention, since the vibration is applied to the driving wheel by driving the load motor, the present invention can be used to measure the influence of the vibration in the vicinity of the driving wheel.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In FIG. 1, a chassis dynamo device 1 according to a first embodiment of the present invention is rotatably supported by a load motor 2 in which a rotor shaft is coupled to a drive wheel 11 of a vehicle 10 so as not to be relatively rotatable, and a machine frame (not shown). The contact ring roller 3 and the compensation motor 4 having a rotor shaft fixed to the rotation shaft of the contact ring roller 3 so as not to be relatively rotatable are configured. The diameter of the contact roller 3 is, for example, 1100 mm. The load motor 2 and the compensation motor 4 are both low inertia AC motors (for example, permanent magnet induction motors). During the test, the load motor 2 operates as power drive or power absorption, and the compensation motor 4 Operates as a power drive.
[0030]
An intermediate shaft 6 is fixed to the tip of the rotor shaft of the load motor 2 via a torque meter 5. As shown in FIG. 2, the flange 6a at the tip of the intermediate shaft 6 is bolted during the test. 7 is fixed to the wheel hub 11 a of the drive wheel 11 via the spacer 8. The torque meter 5 is provided with an electromagnetic pickup for detecting the rotational speed.
[0031]
FIG. 3 is a block diagram showing a configuration example of the control system. In the figure, the control system is mainly configured by a calculation unit 20 that calculates a load command / position command and torque command for the load motor 2 and a position command / torque command for the compensation motor 4. Connected to the output side of the arithmetic unit 20 is a load motor control unit 22 that applies a load to the load motor 2 in a forward and reverse direction, and is variable by changing the current and frequency to the load motor 2. Real load, that is, mechanical load can be applied. Similarly, the compensation motor control unit 24 is connected to the compensation motor 4, and the same control as that of the load motor 2 can be performed. Each of the load motor control unit 22 and the compensation motor control unit 24 includes a known three-phase bridge inverter circuit, and control by this is performed by, for example, a PWM (pulse width modulation) system.
[0032]
The position outputs from the electromagnetic pickups 2a and 4a provided in the load motor 2 and the compensation motor 4 are input to the calculation unit 20, and the compensation motor 4 is synchronized with the rotation angle of the load motor 2 by the position command of the calculation unit 20. And controlled to operate. In addition, the calculation unit 20 includes a vehicle speed signal, a longitudinal load change, a torque change, Each value such as the amount of movement of the center of gravity is input in real time.
[0033]
In addition, a storage unit 25 is connected to the arithmetic unit 20, and in addition to the operation program for the control system itself, various function map format data or model structures and parameters described later are stored in advance. . Such parameters include, for example, shock absorber damping force, shock absorber spring constant, differential gear ratio, and other vehicle specifications, and road surface topography and physical properties such as road gradient and friction coefficient μ. There is something related to.
[0034]
In the present embodiment, the vehicle 10 and the road surface model are calculated by the calculation unit 20 according to various test conditions described later, and the resulting load command is output to the load motor control unit 22 as a control value. The load torque of the load motor 2 is controlled. Since the load torque of the load motor 2 acts on the vehicle 10 as pseudo running resistance, the vehicle 10 can measure various physical quantities under the same conditions as when running on an actual road.
[0035]
At this time, the compensation motor 4 is controlled so that the influence of the contact roller 3 on the drive wheel 11 is cut off and the drive wheel 11 is unloaded with respect to the contact roller 3 side. The compensation motor 4 is controlled by both speed control and torque control.
[0036]
Among these, the speed control is performed so that the speeds of the driving wheel 11 and the contact roller 3 are always equal. Specifically, a load motor 2 that uses the speed ratio determined by the diameters of both the driving wheel 11 and the contact roller 3 to make the rolling contact between the driving wheel 11 and the contact roller 3 without causing slippage. A speed map showing the correspondence between the speed of the motor and the speed of the compensation motor 4 is created in advance and stored in the storage unit 25, and this speed map is used for speed control. Alternatively, a value calculated from the model structure is used for speed control.
[0037]
During operation, this speed map is calculated from the speed value of the load motor 2 (the actual speed of the load motor 2 detected from the electromagnetic pickup 2a or the speed command value for the load motor 2 held by the calculation unit 20). And the speed value of the corresponding compensation motor 4 is acquired. Then, a speed command value for the compensation motor 4 is output to the compensation motor control unit 24 so as to coincide with the acquired speed value, whereby the compensation motor 4 is rotationally controlled synchronously with the load motor 2, and the drive wheel 11 and the contact wheel Both speeds at the contact point of the roller 3 become equal.
[0038]
In the torque control, torque that is equal in magnitude and reverse in direction to the sum of the inertia force of the contact roller 3 and the device loss (that is, drag loss between the contact roller 3 and the compensation motor 4) is compensated for by the motor. The inertial force of the contact roller 3 is canceled (cancelled). Specifically, from the acceleration of the compensation motor 4 obtained as a result of the speed control described above (the differential value of the speed command or the differential value of the actual speed of the compensation motor 4 detected from the electromagnetic pickup 4a), a predetermined acceleration is obtained. -The inertial force of the contact roller 3 is obtained by referring to the inertial force map, a torque command is generated so as to balance the calculated inertial force, and the compensation motor 4 is torque controlled.
[0039]
For example, when the driving wheel 11 is accelerated from a steady running state in which the driving wheel 11 rotates in the A direction and the contact wheel roller 3 rotates in the C direction in FIG. Is applied with torque in the positive direction (C direction). Conversely, when the drive wheel 11 is decelerated, torque in the reverse direction (D direction) is applied to the output to the contact roller 3 by the output of the calculation unit 20. Therefore, the influence of the contact roller 3 on the drive wheel 11 via the contact point E is blocked while the contact roller 3 is supporting a large part of the vehicle weight, and the drive wheel 11 is connected to the contact roller 3. With respect to the running resistance on the side, there is no load as in the case of idling.
[0040]
In the present embodiment, by using a vehicle speed signal that is actually acquired (measured) from the vehicle 10, the running resistance is determined by referring to a vehicle speed-running resistance map (see FIG. 5) that is created in advance and stored in the storage unit 25. Calculated. Then, the load value of the load motor control unit 22 is controlled to the braking side according to the calculated running resistance, and a pseudo running resistance is given to the drive wheels 11 by the load torque of the load motor 2.
[0041]
As described above, in the present embodiment, since the load motor 2 is directly connected to the drive wheels 11 of the vehicle 10, the inertial component in the external mechanical load is limited to that related to the rotor of the load motor 2. Thus, compared with the case where the load motor is directly connected to the contact roller, the influence of the inertial force of the contact roller 3 can be eliminated, and a pseudo load with high responsiveness can be given to the vehicle 10.
[0042]
In the present embodiment, since the control value (current, frequency) of the load motor control unit 22 as variable load means electrically connected to the load motor 2 is controlled by the calculation unit 20, the present invention is applied. The effect can be realized with a simple configuration.
[0043]
In this embodiment, the compensation motor 4 is coupled to the contact roller 3 that contacts the drive wheel 11 with its peripheral surface, and the compensation motor control unit 24 outputs the output of the compensation motor 4 based on the speed of the drive wheel 11. By controlling, the inertia force of the contact roller 3 is decreased. Therefore, in this embodiment, the influence of the inertial force of the contact roller 3 on the drive wheel 11 can be reduced while supporting the weight of the vehicle 10 by the contact roller 3.
[0044]
In this embodiment, the compensation motor 4 that drives the contact roller 3 is driven based on the speed of the drive wheel 11 acquired from the load motor 2, so that the mechanical load applied to the vehicle 10 by the load motor 2 is reduced. The fluctuation and the fluctuation of the inertial force of the contact roller 3 can be synchronized, and a sudden change in traveling conditions can be faithfully reproduced by canceling the inertial force, which is a mechanical loss. Further, the output of the electromagnetic pickup 2 a that is the feedback output of the load motor 2 can be used for the synchronous operation of the compensation motor 4, which is preferable.
[0045]
Next, a second embodiment will be described. In the first embodiment, since the contact roller 3 and the compensation motor 4 are used, the contact area with the wheel such as the drive wheel 11 is expanded by using the large diameter contact roller 3 and traveling due to the ground contact condition is performed. Although the load characteristics such as resistance can be made close to the actual road, the use of the contact roller 3 provided with the compensation motor 4 is not essential in the present invention, as in the second embodiment not using this. It can also be configured.
[0046]
That is, as shown in FIG. 6, a free roller 31 that is supported by a machine frame (not shown) so as to freely rotate is disposed so that the peripheral surface of the drive wheel 11 is in contact with the drive wheel 11. The diameter of the free roller 31 is, for example, 100 mm. The free roller 31 is not provided with the load motor 2 or other load means described above. The remaining configuration of the second embodiment is the same as that of the first embodiment. In the second embodiment, there is an advantage that the apparatus can be designed to be small by reducing the diameter of the free roller 31.
[0047]
Next, a third embodiment will be described. In the third embodiment, no member that contacts and supports the peripheral surface of the drive wheel 11 is provided. As shown in FIG. 7, the load motor 2 is moved up and down as a holding mechanism. The hydraulic jack mechanism 33 is provided, and the vehicle 10 is lifted by the operation of the hydraulic jack mechanism 33 so that the peripheral surface of the drive wheel 11 is not grounded. A lifting arm 34 to which the load motor 2 is fixed is provided with a support arm 35 that rotatably supports an intermediate portion of the intermediate shaft 6 via a bearing (not shown). The remaining configuration of the third embodiment is the same as that of the first embodiment.
[0048]
In the third embodiment, the degree of freedom of operation of the so-called unsprung portion of the wheel is limited unlike the case of actual traveling or the first and second embodiments, but the drive wheel 11 from the ground contact surface is restricted. The influence on can be eliminated. Instead of the configuration in which the load motor 2 is raised and lowered as in the third embodiment, the floor portion 36 on which the vehicle 10 is placed, particularly the portion corresponding to the drive wheels 11 and other wheels, sinks downward in the figure. Further, an appropriate lifting mechanism (not shown) may be provided. In addition, a universal joint may be interposed between the intermediate shaft 6 and the rotor shaft of the load motor 2, and an appropriate portion of the vehicle body of the vehicle 1 may be held to float the driving wheel 11 from the floor portion 36.
[0049]
Next, a fourth embodiment will be described. In the fourth embodiment, other various function maps are used for calculating the running resistance, and a virtual change of the friction coefficient μ between the drive wheel and the road surface is realized. The mechanical configurations in the following embodiments can be applied as they are in the first to third embodiments. In each of the following embodiments, various function maps stored in advance in the storage unit 25 are used. However, instead of the configuration using the function map, a model equation that approximates the same characteristic by experiment is used. May be used.
[0050]
In general, the slip ratio between the drive wheel and the road surface (that is, the ratio of the difference between the peripheral speed of the drive wheel and the road surface speed to the peripheral speed of the drive wheel) and the friction coefficient μ are generally The relationship as shown in FIG. 8 is established. Further, this relationship is dependent on the vehicle speed, and different slip ratio-friction coefficient characteristics (hereinafter referred to as slip characteristics) are established depending on the vehicle speed. In this embodiment, a three-dimensional slip characteristic map in which such a slip characteristic is converted into a function map for each vehicle speed is created in advance and stored in the storage unit 25.
[0051]
During the test, the vehicle speed is monitored, the slip characteristic corresponding to the vehicle speed is calculated (μ is virtually variable), and the running resistance of the load motor 2 is controlled, so that the dry road, wet road surface, ice and snow are controlled. Simulate the slip characteristics of the road.
[0052]
Specifically, the vehicle speed input from the vehicle measuring device is read into the calculation unit 20, and the slip ratio is continuously calculated from the acceleration (derived from the differential value of the vehicle speed) due to the driving operation such as acceleration / deceleration. The friction coefficient μ is calculated by referring to the slip characteristic map at the vehicle speed at that time using the rate. Then, by reflecting the calculated friction coefficient μ with a predetermined function in the rolling resistance value in the vehicle speed-running resistance map described above, the running resistance generated by the load motor 2 is changed in a pseudo manner, and the road surface state The slip state according to the driving operation state can be reproduced.
[0053]
Next, a fifth embodiment will be described. The fifth embodiment realizes virtual reproduction of an actual road by using actual data of a steering angle and a road surface gradient.
[0054]
The drag coefficient and lateral force coefficient of the drive wheel 11 are shown in accordance with the slip angle during cornering (that is, the angle x formed by the traveling direction of the drive wheel 11 and the longitudinal section of the drive wheel 11; see FIG. 9A). The characteristic shown in FIG. 9 (b) (hereinafter referred to as “steer characteristic”) is shown. In this embodiment, a steer characteristic map obtained by converting the steer characteristic into a function map is created in advance and stored in the storage unit 25.
[0055]
Further, by running on a real road (which may be a test course or a public road) in a predetermined section to be tested, the steer angle (steering angle), the wheel speed of each of the left and right drive wheels 11, the engine speed, and the gear position (or speed change) Ratio) and road surface gradient actual data are detected, recorded as a time-series actual road log, and stored in the storage unit 25 in advance.
[0056]
In addition, an electric actuator is installed on the accelerator pedal and the shift lever of the vehicle 10 set in the chassis dynamo device 1, or an input terminal to a throttle actuator or a shift actuator already provided in the vehicle 10 is connected to an external controller. Thus, the device is prepared so that the vehicle 10 is accelerated / decelerated / shifted according to the data of the actual road log.
[0057]
During the test, while driving the vehicle 10 according to the data of the actual road log (acceleration / deceleration operation / shift operation), the slip angle x determined according to the steering angle (steering angle) recorded in the actual road log, Also, the wheel speed data of the left and right drive wheels 11 is read into the calculation unit 20, and the drag coefficient and lateral force of the drive wheels 11 are referred to by using the slip angle x and the wheel speed and referring to the steering characteristic map described above. The coefficient is calculated continuously. Further, the road surface gradient is sequentially read from the actual road log into the calculation unit 20, and a gradient coefficient Wsinθ (W is the vehicle weight and θ is the road surface gradient), which is the degree of influence of the road surface gradient on the running resistance, is calculated.
[0058]
Then, the drag coefficient and lateral force coefficient calculated as described above according to the travel distance accumulated from the speed signal input from the vehicle 10 are set to a predetermined function as the rolling resistance value in the vehicle speed-travel resistance map described above. And the running resistance generated by the load motor 2 is artificially changed and output to the load motor 2 by multiplying the running coefficient by the gradient coefficient. Therefore, according to this embodiment, it is possible to realize a test (for example, a fuel efficiency evaluation test) that freely reproduces the road state and the driving state according to the actual road log, particularly the actual road gradient and corner radius.
[0059]
When the test is performed under the condition of traveling at a constant engine speed and a constant gear ratio, it is not necessary to change the engine speed and the gear ratio of the vehicle 10 according to the actual road log during the test. In this embodiment, the real path log is used. However, a virtual path log having data members corresponding to the real path log may be created in advance, and the test may be performed using the virtual path log.
[0060]
Next, a sixth embodiment will be described. The sixth embodiment realizes an influence evaluation by virtual change of vehicle parameters.
[0061]
In the present embodiment, a change in the characteristics of the vehicle 10 itself, such as a change in the characteristics of the power transmission system, is converted into a running resistance and given to the vehicle, thereby virtually changing the parameters of the vehicle 10 itself. Can be assessed for impact.
[0062]
That is, in the present embodiment, model formulas such as an engine, a transmission, a propeller shaft, a differential, a drive shaft, a driving wheel, a suspension, and a body in an actual test vehicle are created in advance and stored in the storage unit 25. For example, when a two-degree-of-freedom model model in which a member a (for example, a transmission) and a member b (for example, a wheel) are connected in series is considered, the model formula is as follows.
[0063]
[Expression 1]
f (Ma, Ka, Ca, Ja, θa, Mb, Kb, Cb, Jb, θb) = Tload
[0064]
Where T is the vehicle side torque, θ is the shaft twist angle, M is the mass, K is the spring constant, C is the viscosity coefficient, J is the moment of inertia, subscript a is member a, subscript b is member b, and Tload is a load motor. The load torque by 2 is shown.
[0065]
Based on this model formula, the value of the running resistance when the value of the parameter in the model formula is virtually varied is calculated, and the vehicle is loaded by the load motor 2. For example, when it is assumed that the member a is replaced with a member a ′ whose parameters are different from each other by Ma ′, Ka ′, Ca ′, and Ja ′, the load torque Tload ′ loaded by the load motor 2 is the following number. It is represented by 2.
[0066]
[Expression 2]
f (Ma + Ma ′, Ka + Ka ′, Ca + Ca ′, Ja + Ja ′, θa + θa ′, Mb, Kb, Cb, Jb, θb) = Tload ′
[0067]
The load motor control unit 22 is controlled by the calculation unit 20 with the value of the load torque Tload ′ obtained in this way as the target load torque, and a change in the characteristics of the vehicle 10 is performed while loading the vehicle 10 by the load motor 2. taking measurement.
[0068]
In this embodiment, the parameter change is converted into a load torque as a pseudo running resistance by the load motor 2 and is applied to the vehicle 10 as a virtual parameter change. Therefore, each parameter of each member constituting the power transmission system is changed. It is possible to evaluate the influence of individual or arbitrary changes on the vehicle or changes in characteristics, for example, the influence of individual specification parameters on fuel consumption.
[0069]
The parameters that can be changed in this embodiment may be other types. For example, the internal drag loss, the stirring resistance, the transmission efficiency, and the engine water temperature and the warm-up state such as the transmission and the differential are used as parameters. can do.
[0070]
This embodiment can also be used for evaluating the influence of transmission parameter changes on driving force and fuel consumption characteristics. That is, a running resistance equivalent to when the transmission parameters such as a map constant of the torque converter and a transmission shift point are virtually changed in the model equation is calculated, and is changed by loading the vehicle with the load motor 2. It is possible to evaluate the influence of the parameters on driving power and fuel consumption.
[0071]
Next, a seventh embodiment will be described. The seventh embodiment realizes evaluation of vibration transfer characteristics by virtual reproduction of vibration.
[0072]
In this embodiment, the load motor 2 is operated not as power absorption but as power drive by control switching of the load motor control unit 22 (FIG. 3). The fluctuation is input to the drive wheel 11 and the vibration transmission characteristic of the vehicle 10 is evaluated by detecting the vibration with a pressure sensor provided in the vehicle interior. In this embodiment, the wheels directly connected to the load motor 2 may be driven wheels instead of the driving wheels 11.
[0073]
The vibration forcing force to be simulated is the vibration or impact generated from the wheel and its vicinity toward the passenger compartment, such as tire imbalance, non-uniform road noise (vibration caused by road surface irregularities), and brake rotor vibration. Or unbalance. On the other hand, pressure sensors (not shown) are respectively installed in the brake pedal and the steering wheel, which are equipment in the vehicle interior of the vehicle 10. The measurement point in the passenger compartment is preferably a member that can be directly contacted by an occupant during driving.
[0074]
For example, when measuring the vibration transmission characteristics due to the vibration of the brake rotor (that is, the degree to which the vibration due to the vibration of the brake rotor is transmitted to the vehicle interior), the vibration of the brake rotor is measured as shown in FIG. Corresponding rotation primary torque fluctuation is given as a pulsating torque to the load motor 2 by the calculation unit 20 as a standard input value with a constant forcing force, and vibrations of the brake pedal and the steering wheel at that time are measured.
[0075]
According to this embodiment, a plurality of different types of vehicles are tested under the same conditions, thereby comparing vibration sensitivities (vibration transfer characteristics) between vehicle types, or equivalent to an unbalance amount in a vibration forcing force to be simulated. By individually changing parameters such as amplitude, phase, and frequency in the forced vibration force waveform, it is also possible to evaluate vibration transfer characteristics with respect to the forced force, particularly non-linearity.
[0076]
In each of the above embodiments, the load motor 2 is directly connected to the drive wheel 11, but the load motor 2 may be directly connected to a wheel other than the drive wheel 11, that is, a driven wheel. Moreover, although the wheel hub 11a was used for the direct connection between the drive wheel 11 and the load motor 2, other parts or members may be used.
[0077]
In addition, the test conditions used as parameters in the present invention are not only the mechanical characteristics of the vehicle itself and the topographical / physical characteristics of the road surface mentioned in the above embodiments, but also the weather conditions such as the outside temperature / humidity and atmospheric pressure. The physical quantity representing can also be widely selected. In the fourth to seventh embodiments, examples of using various function maps and model expressions individually have been described. However, in the present invention, a plurality of types of function maps and model expressions may be used simultaneously. The apparatus and method according to the present invention are not limited to the types of tests shown in the above embodiments, and can be widely used for various other vehicle tests.
[Brief description of the drawings]
FIG. 1 is a front view schematically showing a first embodiment of the present invention.
FIG. 2 is a cross-sectional view showing a driving wheel in the first embodiment.
FIG. 3 is a block diagram showing a control system of the first embodiment.
FIG. 4 is an explanatory view showing the operation of the contact roller and the compensation motor in the present invention.
FIG. 5 is a graph showing a running resistance map.
FIG. 6 is a side view showing a main part of the second embodiment.
FIG. 7 is a front view showing an outline of a third embodiment.
FIG. 8 is a graph showing a slip characteristic map.
9A is an explanatory diagram showing a relationship between a slip angle and a lateral force, and FIG. 9B is a graph showing a steering characteristic map.
FIG. 10A is a graph showing input torque fluctuations in the seventh embodiment, and FIG. 10B is a graph showing frequency distributions of amplitudes in different vehicles.
FIG. 11 is a front view showing a chassis dynamo device before improvement according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Chassis dynamo device, 2 Load motor, 3 Contacting roller, 4 Compensation motor, 10 Vehicle, 11 Drive wheel, 20 Computation part, 22 Load motor control part, 24 Compensation motor control part, 25 Storage part.

Claims (14)

A load motor directly connected to the drive wheels of the vehicle ;
A contact roller contacting a peripheral surface of the drive wheel;
A compensation motor directly connected to the contact roller,
Compensation control means for controlling the motion of the compensation motor;
With
The chassis dynamo apparatus characterized in that the compensation control means drives the compensation motor based on a physical quantity indicating the motion of the drive wheel acquired from the load motor to reduce the inertial force of the contact roller . The chassis dynamo device according to claim 1,
Variable load means electrically connected to the load motor;
Load control means for controlling the electric load value of the variable load means;
A chassis dynamo device further comprising: The chassis dynamo device according to claim 1 or 2,
A chassis dynamo device further comprising a free roller contacting a peripheral surface of the drive wheel. The chassis dynamo device according to any one of claims 1 to 3,
A chassis dynamo device further comprising a holding mechanism for levitating the peripheral surface of the drive wheel. The chassis dynamo device according to any one of claims 1 to 4,
Further comprising storage means for storing in advance parameters indicating test conditions relating to the vehicle and the road surface;
The chassis dynamo apparatus characterized in that the load control means controls the electric load value of the variable load means in accordance with the parameter stored in the storage means. The chassis dynamo device according to claim 5,
The chassis dynamo device, wherein the load control means controls the electric load value in consideration of a measured value of a state during operation of the vehicle. The chassis dynamo device according to claim 5 or 6,
The chassis dynamo device characterized in that the test condition is a road friction condition. The chassis dynamo device according to claim 5 or 6,
The chassis dynamo device characterized in that the test condition is a road surface gradient. The chassis dynamo device according to claim 5 or 6,
A chassis dynamo device characterized in that the test condition is a curvature of a road surface. The chassis dynamo device according to claim 5 or 6,
A chassis dynamo device characterized in that the test condition is an uneven condition on a road surface. The chassis dynamo device according to claim 5 or 6,
A chassis dynamo device characterized in that the condition of the vehicle is a parameter of a power transmission system. The chassis dynamo device according to claim 5 or 6,
The chassis dynamo device characterized in that the test condition is acquired by an actual running test on a predetermined running route. A vehicle test method using the chassis dynamo device according to claim 1,
Storing parameters indicating test conditions relating to the vehicle and road surface;
Measuring the state of the vehicle while driving;
Calculating an electrical load value based on the stored parameter and the measured value by the measurement;
Controlling the electric load value of the variable load means based on the calculated electric load value;
A vehicle test method including: A vehicle test method using the chassis dynamo device according to any one of claims 1 to 6,
A vehicle test method, wherein vibration is applied to drive wheels by driving a load motor.

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