JP2010011662A - Vehicle controller - Google Patents

Abstract

An object of the present invention is to provide a vehicle control device capable of suppressing slip loss and improving fuel efficiency.
The wheel drive device 3 includes means for adjusting the magnitude of the rotational driving force applied to the wheel 2, and this means reduces the variation in grounding force when the wheel 2 travels on the road surface. Since it is the structure which adjusts the magnitude | size of the rotational drive force given to the wheel 2, the local slip between the wheel 2 and a road surface can be suppressed. As a result, the slip loss can be suppressed and the rotational energy of the wheel 2 can be efficiently transmitted to the road surface, so that the fuel efficiency can be improved accordingly.
[Selection] Figure 1

Description

  The present invention relates to a vehicle control device, and more particularly to a vehicle control device that can suppress slip loss and improve fuel efficiency.

  In recent years, in response to social demands for energy saving and resource saving, research has been conducted to reduce rolling resistance of tires in order to save automobile fuel consumption. In order to reduce the rolling resistance, it is effective to reduce the hysteresis loss of the tread portion, that is, to reduce the loss tangent (tan δ). As a method of reducing this loss factor, a method of blending an inorganic filler such as silica or a silane coupling agent is common.

  However, when an inorganic filler is blended, there is a problem that storage elastic modulus (E ') and the like are lowered. When the storage elastic modulus (E ′) is lowered, the rib rigidity in the tread portion is lowered, and the steering stability is deteriorated. However, since the storage elastic modulus (E ′) is a property that is contrary to the loss tangent (tan δ), it has been difficult to achieve both fuel saving and steering stability.

Then, the method of adding resin is disclosed as a method of improving steering stability, without impairing the fuel-saving property of the rubber | gum which mix | blended the inorganic filler (patent documents 1, 2). A rubber composition containing a compound having a polymerizable unsaturated bond and a specific functional group is also disclosed (Patent Document 3).
JP 2000-80205 A JP 2000-290433 A JP 2002-179841 A

  However, in recent years, there has been a demand for further improvements in tire fuel economy due to environmental considerations, and it is difficult to meet the demand for improvement in fuel efficiency simply by improving the compound physical properties of the tread. There was a problem that there was.

  As a result of diligent investigations on this problem, the present applicant has reduced the occurrence of local slip of the tire due to non-uniformity (nonuniformity in shape, weight, rigidity, etc.) of the wheel (tire and wheel). It has been found that fuel efficiency is deteriorated (however, not known at the time of this application).

  FIG. 10 is a schematic diagram schematically showing the occurrence of a local slip due to the non-uniformity of the wheel 102, and shows the passage of time such as the wheel speed when the wheel 102 rotates about four times.

  For example, even when a constant driving torque is applied to the wheel 102 in order to cause the vehicle to travel at a constant speed, when the wheel travels on the road surface, as shown in FIG. Due to non-uniformity, a partial change occurs in the wheel speed, resulting in a change in ground load. As a result, slip loss due to local slip is generated, so that the rotational energy of the wheel 102 is absorbed, and the fuel efficiency is reduced accordingly.

  The present invention has been made in order to provide a new technique related to fuel efficiency, against the background described above, and can suppress slip loss and improve fuel efficiency. The purpose is to provide.

  In order to achieve this object, the vehicle control device according to claim 1 is used for a vehicle including a wheel and a driving device that applies a rotational driving force to the wheel, and the driving device is the wheel. The driving force adjusting means adjusts the magnitude of the rotational driving force applied to the wheel, and the driving force adjusting means is a variation in the contact force generated due to the non-uniformity of the wheel when the wheel travels on the road surface. The magnitude of the rotational driving force applied to the wheel is adjusted so as to be small.

  The vehicle control device according to claim 2 is the vehicle control device according to claim 1, wherein an adjustment ratio when the magnitude of the rotational driving force applied to the wheel by the driving force adjusting means is adjusted to the wheel. An adjustment ratio storage means for storing the phase of the wheel in association with a phase acquisition means for acquiring the phase of the wheel, and the driving force adjustment means corresponds to the phase of the wheel acquired by the phase acquisition means. The adjustment ratio to be read is read from the adjustment ratio storage means, and the magnitude of the rotational driving force applied to the wheel is adjusted based on the read adjustment ratio.

  The vehicle control device according to claim 3 is the vehicle control device according to claim 2, wherein speed acquisition means for acquiring the vehicle speed of the vehicle, vehicle speed of the vehicle acquired by the speed acquisition means, and the vehicle Speed-dependent adjustment ratio acquisition means for acquiring the adjustment ratio according to the phase of the wheel obtained by the phase acquisition means, and the driving force adjustment means acquires the adjustment acquired by the speed-dependent adjustment ratio acquisition. Based on the ratio, the magnitude of the rotational driving force applied to the wheel is adjusted.

  The vehicle control device according to claim 4 is the vehicle control device according to claim 2 or 3, wherein when the wheel travels on a road surface, a variation in grounding force caused by non-uniformity of the wheel is generated. The adjustment generated by the adjustment ratio generation means, and the adjustment ratio generation means for generating the adjustment ratio based on the fluctuation of the contact force acquired by the fluctuation acquisition means. The ratio is stored in the adjustment ratio storage means, and the change in the ground contact force is acquired by the change acquisition means while the vehicle is running.

  According to the vehicle control device of the first aspect, the driving device is operated, and the driving force is applied to the wheels from the driving device, whereby the wheels are rotated and the vehicle is driven.

  Here, when the wheel travels on the road surface, due to the non-uniformity of the wheel, a partial change occurs in the wheel speed, resulting in a change in ground load. The fluctuation of the ground contact load causes slip loss due to local slip between the wheel and the road surface, and the rotational energy of the wheel is absorbed, thereby deteriorating fuel efficiency.

  On the other hand, according to the present invention, the driving device includes a driving force adjusting means that adjusts the magnitude of the rotational driving force applied to the wheel, and the driving force adjusting means is a grounding force when the wheel travels on the road surface. Since it is the structure which adjusts the magnitude | size of the rotational drive force given to a wheel so that the fluctuation | variation of this may be made small, the local slip between a wheel and a road surface can be suppressed. As a result, the slip loss can be suppressed and the rotational energy of the wheels can be efficiently transmitted to the road surface, so that there is an effect that the fuel economy can be improved correspondingly.

  According to the vehicle control device of the second aspect, in addition to the effect produced by the vehicle control device according to the first aspect, the adjustment ratio when adjusting the magnitude of the rotational driving force applied to the wheels by the driving force adjusting means. Is stored in association with the phase of the wheel, and a phase acquisition unit that acquires the phase of the wheel, and the driving force adjustment unit adjusts the phase corresponding to the phase of the wheel acquired by the phase acquisition unit. Since the ratio is read from the adjustment ratio storage means and the magnitude of the rotational driving force applied to the wheel is adjusted based on the read adjustment ratio, the variation in the contact force due to the non-uniformity of the wheel Can be adjusted for each rotation position (phase).

  As a result, it is possible to reliably reduce the fluctuation of the ground contact force when the wheel travels on the road surface, and to effectively suppress the local slip between the wheel and the road surface. As a result, the slip loss can be suppressed and the rotational energy of the wheels can be efficiently transmitted to the road surface, so that the fuel efficiency can be improved accordingly.

  In addition, as in the present invention, if the adjustment ratio storage means is provided that stores the adjustment ratio in association with the phase, the adjustment ratio corresponding to the rotation position (phase) that is next brought into contact with the road surface is adjusted. By pre-reading from the storage means, the magnitude of the rotational driving force applied to the wheel can be adjusted appropriately in accordance with the timing at which the rotational position (phase) contacts the road surface.

  Thereby, the fluctuation | variation of the ground contact force at the time of a wheel drive | working a road surface can be made small reliably, and the local slip between a wheel and a road surface can be suppressed effectively. As a result, the slip loss can be suppressed and the rotational energy of the wheels can be efficiently transmitted to the road surface, so that the fuel efficiency can be improved accordingly.

  According to the vehicle control device of the third aspect, in addition to the effect produced by the vehicle control device according to the second aspect, the speed acquisition means for acquiring the vehicle speed of the vehicle, and the vehicle acquired by the speed acquisition means. Speed-dependent adjustment ratio acquisition means for acquiring an adjustment ratio according to the vehicle speed and the phase of the wheel obtained by the phase acquisition means, and the driving force adjustment means obtains the adjustment ratio acquired by the speed-dependent adjustment ratio acquisition. Based on the configuration, the magnitude of the rotational driving force applied to the wheel is adjusted, so that the magnitude of the rotational driving force applied to the wheel can be appropriately adjusted.

  That is, the ground contact force of the wheel differs (varies) for each rotational position (phase) due to its non-uniformity, but the variation in this ground force also depends on the vehicle speed, so the same rotational position of the wheel. Even in (phase), the magnitude of the ground contact force varies depending on the vehicle speed.

  In this case, according to the present invention, the speed-dependent adjustment ratio acquisition means is configured to acquire not only the phase of the wheel but also the adjustment ratio according to the phase and the vehicle speed. The size can be adjusted appropriately regardless of the vehicle speed.

  Thereby, the fluctuation | variation of the ground contact force at the time of a wheel drive | working a road surface can be made small reliably, and the local slip between a wheel and a road surface can be suppressed effectively. As a result, the slip loss can be suppressed and the rotational energy of the wheels can be efficiently transmitted to the road surface, so that the fuel efficiency can be improved accordingly.

  According to the vehicle control device of the fourth aspect, in addition to the effect produced by the vehicle control device according to the second or third aspect, the vehicle is generated due to the non-uniformity of the wheel when traveling on the road surface. The adjustment generated by the adjustment ratio generation means is provided with a fluctuation acquisition means for acquiring the fluctuation of the contact force and an adjustment ratio generation means for generating an adjustment ratio based on the fluctuation of the contact force acquired by the fluctuation acquisition means. Since the ratio is stored in the adjustment ratio storage means and the change in the contact force by the fluctuation acquisition means is performed while the vehicle is running, the adjustment ratio in consideration of the state of the wheels and the vehicle can be generated. As a result, there is an effect that fuel consumption can be further improved.

  For example, in a configuration in which a change in ground contact force is obtained for a new wheel at the time of factory shipment and an adjustment ratio is generated based on the change, the wear of the wheel due to running or a change in rubber characteristics over time, etc. When changes occur in the non-uniformity of the wheels, the changes cannot be taken into account, so the rotational drive force applied to the wheels cannot be properly adjusted, and the grounding force fluctuations must be reduced. It becomes difficult.

  On the other hand, according to the present invention, since the adjustment ratio can be generated based on the fluctuation of the contact force acquired during the traveling of the vehicle, for example, even when the wear of the wheel or the change in the rubber characteristics with time occurs. An adjustment ratio that takes this change into account can be generated. Similarly, for example, when the wheel temperature changes due to the road surface temperature, when the wheel air pressure increases or decreases, or when the shared load changes due to the number of passengers or luggage of the vehicle, etc. Proportion can be generated.

  As a result, the magnitude of the rotational driving force applied to the wheel can be appropriately adjusted regardless of the state change of the wheel or the vehicle. Thereby, the fluctuation | variation of the ground contact force at the time of a wheel drive | working a road surface can be made small reliably, and the local slip between a wheel and a road surface can be suppressed effectively. As a result, the slip loss can be suppressed and the rotational energy of the wheels can be efficiently transmitted to the road surface, so that the fuel efficiency can be improved accordingly.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic diagram schematically showing a vehicle 1 on which a vehicle control device 100 according to the first embodiment of the present invention is mounted.

  First, a schematic configuration of the vehicle 1 will be described. As shown in FIG. 1, the vehicle 1 includes a vehicle body frame BF, a plurality of (four wheels in the present embodiment) wheels 2 supported by the vehicle body frame BF, and a wheel drive device that rotationally drives the wheels 2. 3, a suspension device 4 that suspends each wheel 2 in a floatable state on the vehicle body frame BF, and a steering device 5 that transmits the steering operation of the steering 63 to the wheel 2. By reducing the variation in contact load due to the property and reducing slip loss, the rotational energy of the wheels can be efficiently transmitted to the road surface, and fuel efficiency can be improved accordingly. Has been.

  Next, the detailed configuration of each part will be described. As shown in FIG. 1, the wheel 2 includes four wheels, that is, left and right front wheels 2FL and 2FR positioned on the front side in the traveling direction of the vehicle 1 and left and right rear wheels 2RL and 2RR positioned on the rear side in the traveling direction.

  As described above, the wheel driving device 3 is a rotational driving device for independently rotating each wheel 2 and, as shown in FIG. 1, four electric motors (FL to RR motors 3FL to 3RR). Are arranged on the left and right front wheels 2FL, 2FR and the left and right rear wheels 2RL, 2RR (that is, as an in-wheel motor).

  Here, the wheel driving device 3 is configured as a regenerative motor, and regenerates the rotational energy of the wheel 2 as electric energy, and generates braking force for decelerating the vehicle speed by inhibiting the rotation of the wheel 2. It is configured to be operable as a regenerative brake. The electric power generated by the regeneration is stored in a battery (not shown) configured as a power storage device, and the wheel driving device 3 is driven by the power supplied from the battery.

  As described above, the suspension device 4 is a part that functions as a suspension for floatingly connecting the wheels 2 (front and rear wheels 2FL to 2RR) to the vehicle body frame BF, and corresponds to each wheel 2 as shown in FIG. Are arranged in four places. The FL to RR motors 3FL to 3RR of the wheel drive device 3 are also suspended by the suspension device 4 together with the wheels 2.

  Here, in the present embodiment, the suspension device 4 is configured as a strut suspension. However, in FIG. 1, in order to simplify the drawing and facilitate understanding, illustration of a shock absorber, a control arm, and the like is omitted.

  The steering device 5 is a rack and pinion type steering device for steering the left and right front wheels 2FL and 2FR in accordance with the operation of the steering 63 when operated by the driver. According to the steering device 5, the driver's steering operation (rotation) is first transmitted as a rotational motion to the steering box 53 through the steering column 51 while changing the angle by the universal joint 52. Then, the rotational motion is converted into a linear motion by the steering box 53, and the tie rod 54 moves to the left and right to push and pull the knuckle 55, thereby giving a predetermined steering angle to the left and right front wheels 2FL and 2FR.

  The accelerator pedal 61 and the brake pedal 62 are operation members operated by the driver, and the traveling speed and braking force of the vehicle 1 are determined according to the depression state (depression amount, depression speed, etc.) of each pedal 61, 62. Then, operation control of the wheel drive device 3 and a braking device (a mechanical braking device and a wheel drive device 3 as a regenerative brake (not shown)) are performed by the vehicle control device 100 described later.

  The vehicle control device 100 is a control device for controlling each part of the vehicle 1 configured as described above. For example, the rotational driving force applied from the wheel driving device 3 to the wheel 2 is applied to the rotational position of the wheel 2. By adjusting according to (phase), the fluctuation of the ground load of the wheel 2 is reduced, and the fuel efficiency is improved by reducing the slip loss.

  Next, a detailed configuration of the vehicle control device 100 will be described with reference to FIG. FIG. 2 is a block diagram showing an electrical configuration of the vehicle control device 100. As shown in FIG. 2, the vehicle control apparatus 100 includes a CPU 71, an EEPROM 72, and a RAM 73, which are connected to an input / output port 75 via a bus line 74. A plurality of devices such as the wheel driving device 3 are connected to the input / output port 75.

  The CPU 71 is an arithmetic unit that controls each unit connected by the bus line 74. The EEPROM 72 is a rewritable nonvolatile memory storing a control program executed by the CPU 71, fixed value data, and the like, and the RAM 73 is a memory for storing various data in a rewritable manner when the control program is executed. .

  The EEPROM 72 stores a program of a flowchart (wheel control process) shown in FIG. Further, as shown in FIG. 2, the EEPROM 72 is provided with a rotation angle torque correction map 72a and a speed torque correction map 72b. Here, the rotation angle torque correction map 72a and the speed torque correction map 72b will be described with reference to FIG.

  FIG. 3A is a schematic diagram schematically illustrating the contents of the rotation angle torque correction map 72a, and FIG. 3B is a schematic diagram schematically illustrating the contents of the speed torque correction map 72b. .

  The rotation angle torque correction map 72a is a map that stores the relationship between the rotation angle θ of the wheel 2 and the torque correction value C, and a value measured using a test device for a new wheel 2 mounted on the vehicle 1 is obtained. It is remembered. In the present embodiment, a total of four maps are stored for each wheel 2.

  The rotation angle θ is an absolute circumferential position (phase) of the wheel 2, and a predetermined reference position of the wheel 2 is set to 0 °. The wheel 2 is mounted on the vehicle 1 in a state where its reference position (rotation angle θ = 0 °) can be recognized by a wheel rotation number sensor device 35 described later.

  The torque correction value C is a value for correcting the rotational driving force (driving torque) applied to the wheel 2 according to the rotational angle θ of the wheel 2. That is, when the rolling tester is used and the wheel 2 to which a constant rotational driving force (driving torque) is applied is caused to roll straight in a condition where the rolling radius is constant, the non-uniformity of the wheel 2 is caused. As a result, the ground load varies. As shown in FIG. 3 (a), a value derived in correspondence with the rotational position θ of the wheel 2 is a torque derived from the correction value necessary for minimizing the variation in the ground load (constant the ground load). Correction value C.

  The speed torque correction map 72b is a map in which the relationship between the vehicle speed V and the torque correction coefficient R is stored, and a value measured using a test device for a new wheel 2 mounted on the vehicle 1 is stored. . In the present embodiment, a total of four maps are stored for each wheel 2.

  The vehicle speed V is the ground speed of the vehicle 1, and the torque correction coefficient R is a rotational driving force (drive torque) applied to the wheel 2 according to the ground speed of the vehicle 1 (that is, the wheel speed of the wheel 2). This is a value for correction.

  That is, the rotation angle torque correction map 72a (see FIG. 3A) described above changes only the amplitude (vehicle speed V) while maintaining the waveform according to the speed of the vehicle 1 (the wheel speed of the wheel 2). Accordingly, only the magnitude of the torque correction value C with respect to the rotation angle θ changes). A value obtained by correlating the rate of change of the amplitude with the vehicle speed V is the torque correction coefficient R.

  When the CPU 71 (see FIG. 2) instructs the wheel drive device 3 to drive the wheels 2 to rotate, first, the CPU 71 (see FIG. 1) detects the operation state of the accelerator pedal 61 (see FIG. 1), and the target vehicle of the vehicle 1 from the detection result The rotational driving force T necessary for grasping the speed and obtaining the target vehicle speed is calculated, and the rotational angle θ and the vehicle speed are calculated using the maps 72a and 72b for the calculated rotational driving force T. Correct according to V.

  Specifically, if the rotation angle θ of the wheel 2 is 90 ° and the target vehicle speed V detected from the operation state of the accelerator pedal 61 is Va, the CPU 71 sets the rotation angle torque correction map 72a (FIG. 3 ( a)), the torque correction value C = Ca and the torque correction coefficient R = Ra are read from the speed torque correction map 72b (see FIG. 3B), and each read value is the target rotational drive. The corrected rotational driving force T ′ is calculated by multiplying the force (driving torque) T (T ′ = T × (1 + Ca / 100) × Ra).

  Then, the calculated rotational driving force (driving torque) T ′ after correction is output to the vehicle driving device 3 as a command torque. The vehicle driving device 3 applies the command torque (corrected rotational driving force T ′) to the wheels 2 to rotationally drive the wheels 2. Thereby, since the fluctuation | variation of the ground contact force at the time of the wheel 2 drive | working a road surface can be made small, and slip loss can be suppressed, the improvement in fuel-consumption property can be aimed at.

  Returning to FIG. As described above, the wheel driving device 3 is a device for rotationally driving the wheel 2, and the four FL to RR that apply rotational driving force to the left and right front wheels 2FL, 2FR and the left and right rear wheels 2RL, 2RR. It mainly includes motors 3FL to 3RR and a drive circuit (not shown) that drives and controls each of the motors 3FL to 3RR based on a command from the CPU 71.

  Here, the wheel drive device 3 also functions as a regenerative device as described above. That is, the wheel drive device 3 includes a regenerative circuit (not shown) in addition to the drive circuit. The regenerative circuit incorporates an inverter that converts alternating current into direct current, and based on a control signal from the CPU 71, the FL to RR motors 3FL to 3RR function as a regenerative motor, thereby converting the rotational energy of each wheel 2 into electricity. Regeneration is performed as energy, and electric power generated by the regeneration is supplied to a battery (not shown) and stored. In this embodiment, a battery that is a storage battery is described as an example of a power storage device, but a capacitor may be used as long as electrical energy can be stored.

  The vehicle speed sensor device 32 is a device for detecting the speed (absolute value and traveling direction) of the vehicle 1 with respect to the road surface and outputting the detection result to the CPU 71. The longitudinal and lateral acceleration sensors 32a and 32b, A processing circuit (not shown) that processes the detection results of each of the acceleration sensors 32a and 32b and outputs the result to the CPU 71 is provided.

  The longitudinal acceleration sensor 32a is a sensor that detects the acceleration in the longitudinal direction (the vertical direction in FIG. 1) of the vehicle 1 (body frame BF), and the lateral acceleration sensor 32b is the lateral direction of the vehicle 1 (body frame BF) ( FIG. 1 is a sensor that detects acceleration in the left-right direction. In the present embodiment, each of the acceleration sensors 32a and 32b is configured as a piezoelectric sensor using a piezoelectric element.

  The CPU 71 time-integrates the detection results (acceleration values) of the respective acceleration sensors 32a and 32b input from the vehicle speed sensor device 32 to calculate speeds in two directions (front and rear and left and right directions), respectively. By combining the components, the vehicle speed (absolute value and traveling direction) of the vehicle 1 can be obtained.

  The wheel rotation speed sensor device 35 is a device for detecting the rotation speed of each wheel 2 and outputting the detection result to the CPU 71. Four FL to RR rotations for detecting the rotation speed of each wheel 2 respectively. Number sensors 35FL to 35RR, and a processing circuit (not shown) for processing the detection results of the rotational speed sensors 35FL to 35RR and outputting the results to the CPU 71.

  In the present embodiment, each rotation sensor 35FL to 35RR is provided on each wheel 2 so that the rotation angle θ of each wheel 2 can be detected. That is, each of the rotation sensors 35FL to 35RR includes a rotating body that rotates in conjunction with each wheel 2 and a pickup that electromagnetically detects the presence or absence of a large number of teeth formed on the rotating body at predetermined intervals in the circumferential direction. It is configured as an electromagnetic pickup type sensor provided. The CPU 71 can obtain the rotation angle θ (the reference position and the rotation angle from the reference position) of each wheel 2 from the detection result input from the wheel rotation speed sensor device 35.

  The accelerator pedal sensor device 61a is a device for detecting the operation state of the accelerator pedal 61 (see FIG. 1) and outputting the detection result to the CPU 71, and an angle sensor for detecting the depression state of the accelerator pedal 61 (FIG. And a control circuit (not shown) for processing the detection result of the angle sensor and outputting it to the CPU 71. Examples of the other input / output device 36 include an angle sensor that detects an operation state of the brake pedal 62.

  Next, the wheel control process will be described with reference to FIGS. 4 and 5. FIG. 4 is a flowchart showing the wheel control process. This process is a process that is repeatedly executed by the CPU 71 (for example, at intervals of 0.2 ms) while the power of the vehicle control device 100 is turned on, and controls the driving torque of the wheel 2 by the wheel driving device 3. Thus, by reducing the fluctuation of the ground load of the wheel 2, slip loss is reduced and fuel efficiency is improved.

  FIG. 5 is a schematic diagram schematically showing the state of the wheel 2 to which the wheel control processing is applied. FIG. 10 (that is, the occurrence of local slip due to the non-uniformity of the wheel 2 is schematically shown). This corresponds to the schematic diagram shown in the figure. That is, in FIG. 5, as in FIG. 10, the wheel 2 has non-uniformity only in a part in the circumferential direction, and the time passage such as the wheel speed when the wheel 2 rotates about 4 times is shown.

  Regarding the wheel control processing, the CPU 71 first detects the rotation angle θ of the wheel 2 and the vehicle speed V of the vehicle 1 (S1, S2), and then detects the operation state of the accelerator pedal 61 (S3). ), And shifts to the processing after S4. These processes are performed using the wheel rotation speed sensor device 35, the vehicle speed sensor device 32, and the accelerator pedal sensor device 61a as described above (see FIG. 2).

  In the process of S4, the torque correction value C corresponding to the rotation angle θ of the wheel 2 detected in the process of S1 is read from the rotation angle torque correction map 72a (see FIGS. 1 and 3A) (S4). For example, if the rotation angle θ of the wheel 2 is 90 °, the CPU 71 reads Ca as the torque correction value C from the rotation angle torque correction map 72a (see FIG. 3A).

  In the process of S5, the torque correction coefficient R corresponding to the vehicle speed V of the vehicle 1 detected in the process of S2 is read from the speed torque correction map 72b (see FIGS. 1 and 3B) (S5). For example, if the vehicle speed V is Va, the CPU 71 reads Ra as the torque correction coefficient R from the speed torque correction map 72b (see FIG. 3B).

  In the process of S6, a driving torque (rotational driving force) T ′ is calculated from the operation state of the accelerator pedal 61 detected in the process of S3 and the torque correction value C and the torque correction coefficient R read out in the processes of S4 and S5. (S6).

  Specifically, as described above, if the target vehicle speed ascertained from the operation state of the accelerator pedal 61 is T, each of the target rotational driving force (driving torque) T read in S4 and S5 is read. The corrected rotational driving force T ′ is calculated as T ′ = T × (1 + Ca / 100) × Ra (S6).

  After calculating the drive torque T 'in the process of S6, the wheel drive device 3 is driven with the calculated drive torque T' (S7). As a result, since the wheel 2 can be rotationally driven with the corrected drive torque T ′, the fluctuation of the grounding force when the wheel 2 travels on the road surface can be reduced, and slip loss can be suppressed. The fuel efficiency can be improved accordingly.

  In other words, in the conventional vehicle, when the wheel 102 has non-uniformity, the driving torque is constant, and therefore, a partial change in the wheel speed causes a change in the ground load and a slip loss due to a local slip occurs. As a result, the rotational energy of the wheel 102 is absorbed, and the fuel efficiency is reduced accordingly (see FIG. 10).

  On the other hand, in the present invention, even when non-uniformity exists in the wheel 2, a correction value (torque correction value C) for minimizing the variation of the ground load according to the rotational position (phase) of the wheel 2 is set. The rotational driving force (driving torque) T can be corrected based on the torque correction value C read out from the rotational angle torque correction map 72a. That is, as shown in FIG. 5, the variation in the ground load can be reduced by changing the driving torque at a portion where the wheel speed partially changes due to the non-uniformity of the wheel 2. As a result, the fluctuation of the contact force when the wheel 2 travels on the road surface can be reduced to suppress the slip loss, and the fuel efficiency can be improved accordingly.

  FIG. 5 shows a case where non-uniformity exists only in a part of the circumferential direction of the wheel 2 and the rotational driving force (driving torque) T is corrected only at a part of rotational positions (phases). However, this is only an example, and when there is non-uniformity over the entire circumference of the wheel 2, according to the non-uniformity (that is, using the torque correction value C as shown in FIG. 3A). Of course, it is possible to correct the rotational driving force (driving torque) T over the entire circumference.

  Next, a second embodiment will be described with reference to FIGS. FIG. 6 is a block diagram illustrating an electrical configuration of the vehicle control device 200 according to the second embodiment.

  In the first embodiment, the case where the rotation angle torque correction map 72a and the speed torque correction map 72b are created in advance has been described. However, in the second embodiment, the rotation angle torque correction map 273a and the speed torque correction map are described. 273b is created while the vehicle 1 is traveling. In addition, the same code | symbol is attached | subjected to the part same as above-described 1st Embodiment, and the description is abbreviate | omitted.

  As shown in FIG. 6, the CPU 71 includes a ROM 272 and a RAM 273 and is connected by a bus line 74. The ROM 272 is a non-rewritable nonvolatile memory storing a control program executed by the CPU 71, fixed value data, and the like, and the RAM 273 is a memory for storing various data in a rewritable manner when the control program is executed. . The RAM 273 is provided with a rotation angle torque correction map 273a and a speed torque correction map 273b.

  The rotation angle torque correction map 273a is a map that stores the relationship between the rotation angle θ of the wheel 2 and the torque correction value C, similarly to the rotation angle torque correction map 72a in the first embodiment (see FIG. 3A). A total of four maps are stored for each wheel 2. However, in the present embodiment, values actually measured while the vehicle 1 is traveling are stored.

  Similarly, the speed torque correction map 273b is a map that stores the relationship between the vehicle speed V and the torque correction coefficient R in the same manner as the speed torque correction map 72b in the first embodiment (see FIG. 3B). A total of four maps are stored for each wheel 2. However, in the present embodiment, values actually measured while the vehicle 1 is traveling are stored.

  The load sensor device 234 detects the load (ground force) in the vehicle front-rear direction (the vertical direction in FIG. 1) generated between the wheel 2 and the road surface on which the wheel 2 travels, and outputs the detection result to the CPU 71. For detecting the loads received by the left and right front wheels 2FL, 2FR and the left and right rear wheels 2RL, 2RR, and the detection results of the FL-RR load sensors 234FL-234RR. And a processing circuit (not shown) for processing and outputting to the CPU 71.

  The FL to RR load sensors 234FL to 234RR are configured as piezoresistive load sensors and are disposed on the hub of the wheel 2. The CPU 71 creates the rotation angle torque correction map 273a and the speed torque correction map 273b based on the detection results (loads in the vehicle longitudinal direction) of the FL to RR load sensors 234FL to 234RR input from the load sensor device 234.

  Next, the map creation process will be described with reference to FIG. FIG. 7 is a flowchart showing the map creation process. This process is a process that is repeatedly executed by the CPU 71 (for example, at intervals of 0.2 ms) while the power of the vehicle control device 200 is turned on, and the rotational angle torque correction map 273a and the vehicle 1 are traveling while the vehicle 1 is traveling. A speed torque correction map 273b is created.

  Regarding this map creation processing, the CPU 71 first determines whether or not the rotation angle torque correction map 273a and the speed torque correction map 273b have been created (S21), and determines that both maps 273a and 273b have been created. If it is to be performed (S21: Yes), it is not necessary to create both maps 273a, 273b, so the processing after S22 is skipped and the map creation processing is terminated.

  On the other hand, in the process of S21, when it is determined that both maps 273a and 273b have not been created (S21: No), the processes after S22 are executed to create these maps 273a and 273b. When creating the maps 273a and 273b, first, the vehicle speed of the vehicle 1 is detected (S22), and it is determined whether or not the detected vehicle speed is the vehicle speed for which the rotation angle torque correction map 273a has been created. (S23).

  Here, as described above, the contents of the rotation angle torque correction map 273a have different characteristics depending on the vehicle speed of the vehicle 1 (that is, the waveform of the torque correction value C with respect to the rotation angle θ is the same and the amplitude is different). Therefore, in the present embodiment, the rotation angles at a plurality of vehicle speeds (in this embodiment, three types of low speed (5 km / h), medium speed (30 km / h) and high speed (60 km / h)). A torque correction map (relationship between the rotation angle θ and the torque correction value C, see FIG. 3A) is created, and the three types of results are linearly complemented to obtain a speed torque correction map 273b (FIG. 3B). Browse).

  In the process of S23, when it is determined that the vehicle speed detected in the process of S22 (that is, the current vehicle speed) is the vehicle speed for which the rotation angle torque correction map has already been created (S23: Yes), this Since it is not necessary to create a rotation angle torque correction map at the vehicle speed, the process proceeds to S22 until the vehicle speed of the vehicle 1 matches a predetermined vehicle speed (any one of the three types of vehicle speeds described above). Wait (S22, S23: Yes).

  On the other hand, in the process of S23, when it is determined that the current vehicle speed is not the vehicle speed for which the rotation angle torque correction map has been created (S23: No), the vehicle speed of the vehicle 1 is a predetermined vehicle speed (described above). Any one of the three types of vehicle speeds) has been reached, so that the process proceeds to S24 and subsequent steps in order to create a rotation angle torque correction map at the predetermined vehicle speed.

  In creating the rotation angle torque correction map, first, the contact force at the rotation angle θ is detected (S24), and a predetermined increment α (α = 3 ° in the present embodiment) is added to the rotation angle θ ( S25) The processes of S24 and S25 are repeatedly executed until the execution for one rotation of the wheel 2 is completed (S26: No). The contact force is detected for each wheel 2 using the load sensor device 234 (see FIG. 6).

  In the process of S26, when it is determined that the detection of the contact force is completed for one rotation of the wheel 2 (S26: Yes), a rotation angle torque correction map creation process (S27) is executed to execute the predetermined vehicle. A rotational angle torque correction map at speed is created. Specifically, the torque for each rotation angle θ based on the variation of the contact force at each rotation angle θ (in this embodiment, 0 °, 3 °, 6 °,..., 354 °, 357 °). Each correction value C is calculated.

  In this case, it is assumed that the ground contact force at each rotation angle θ is detected under the condition that the vehicle speed of the vehicle 1 and the rotational drive force (drive torque) of the wheel drive device 3 are constant. When detecting the ground contact force at each rotation angle θ (S24), the rotational driving force of the wheel driving device 3 is kept constant even if the accelerator pedal 61 is operated at least until the wheel 2 rotates once. You may comprise so that it may maintain. Thereby, the accuracy of the torque correction value C can be improved.

  After creating the rotation angle torque correction map at a predetermined vehicle speed (any one of the three types of speeds described above) by the process of S27, the process proceeds to S28, and the rotation angle torque correction map has not been created. It is determined whether or not there is a speed (S28). As a result, when it is determined that there is a vehicle speed for which a rotation angle torque correction map has not been created (S28: Yes), the process of S22 is shifted to create a rotation torque correction map at that vehicle speed, The process described above is executed.

  On the other hand, in the process of S28, when it is determined that there is no vehicle speed for which the rotation angle torque correction map has not been created (S28: No), the rotation angle torque for the three types of vehicle speeds, low speed, medium speed, and high speed. Since the creation of the correction map has been completed, the speed torque correction map 273b (FIG. 3 (FIG. 3) is executed by executing the speed torque correction map creation process (S29) and linearly complementing the three types of results. b) create).

  In the present embodiment, the rotation angle torque correction map for the medium vehicle speed is stored in the RAM 273 as the rotation torque correction map 273a. Therefore, in the speed torque correction map 273b, the torque correction coefficient R at medium speed (30 km / h) is 1, and the torque correction coefficient R is larger than 1 at higher speed than the medium speed (1 <R). On the lower speed side, the torque correction coefficient R is smaller than 1 (R <1).

  After executing the speed torque correction map creation process (S29), the map creation process is terminated. Thereby, since the rotation angle torque correction map 273a and the speed torque correction map 273b are stored in the RAM 273, when the CPU 71 instructs the wheel drive device 3 to drive the rotation of the wheel 2 thereafter, the first described above. As in the case of the embodiment, the rotational driving force T is calculated based on the operation state of the accelerator pedal 61 (see FIG. 1), and both maps 273a and 273b are used for the calculated rotational driving force T. Thus, the corrected rotational driving force T ′ according to the rotational angle θ and the vehicle speed V is calculated.

  Next, a third embodiment will be described with reference to FIGS. FIG. 8 is a block diagram showing an electrical configuration of the vehicle control device 300 according to the third embodiment.

  In 1st Embodiment, although the case where the magnitude | size of the rotational driving force provided to the wheel 2 was controlled based on the rotation angle torque correction map 72a and the speed torque correction map 72b was demonstrated, in 3rd Embodiment, The magnitude of the rotational driving force applied to the wheel 2 is controlled based on the torque average value for the latest one rotation. In addition, the same code | symbol is attached | subjected to the part same as each above-mentioned embodiment, and the description is abbreviate | omitted.

  The CPU 71 includes a RAM 373, which is a memory for storing various data in a rewritable manner when the control program is executed, and the RAM 373 is provided with a rotation angle torque memory 373a as shown in FIG. . The turning angle memory 373a is a memory that stores the relationship between the rotation angle θ of the wheel 2 and the torque at the rotation angle θ, and a total of four areas are secured for each wheel 2.

  Next, the map creation process will be described with reference to FIG. FIG. 9 is a flowchart showing the wheel control process. This process is a process that is repeatedly executed by the CPU 71 (for example, at intervals of 0.2 ms) while the power of the vehicle control device 300 is turned on, and calculates an average value of the torque that acts on the wheels 2; Based on the average value, the rotational driving force (driving torque) applied to the wheel 2 is controlled.

  Regarding the wheel control process, the CPU 71 first detects the torque at the rotation angle θ (S31), and stores the detected torque value in the rotation angle torque memory 373a (S32). Next, a predetermined increment α (α = 3 ° in the present embodiment) is added to the rotation angle θ (S33), and the processing of S31 and S32 is completed for one rotation of the wheel 2. It repeats until it does (S34: No).

  The wheel drive device 3 is configured such that torque sensors are mounted on the drive shafts of the motors 3FL to 3RR, and the torque acting on each wheel 2 can be detected by the torque sensor.

  The rotation angle torque memory 373a is configured as an annular ring memory, and stores data for predetermined rotations (two rotations in the present embodiment) while sequentially updating (that is, data for two rotations is stored). Until the torque is stored, the torque value is accumulated every time the torque at the rotation angle θ is detected by the process of S31, and after the data for two rotations has already been stored, the shift process is performed. Only the data (torque) for the two most recent rotations is stored).

  In the process of S34, when it is determined that the torque for one rotation of the wheel 2 has already been stored in the rotation angle torque memory 373a (S34: Yes), the data stored in the rotation angle torque memory 373a. Based on the above, an average value of torque in the latest one rotation is calculated (S35), and the process proceeds to S36.

  In the process of S36, the average value calculated in the process of S35 is compared with the torque detected this time (that is, the torque detected in the process of S31) (S36), and the drive torque is calculated based on the comparison result. The wheel drive device 3 is driven with the calculated drive torque (S37), and the wheel control process is terminated.

  Specifically, in the process of S36, when the torque detected this time is larger than the average value, it means that the ground load is increased due to the non-uniformity of the wheel 2, so the process of S37. Then, the wheel driving device 3 is controlled so as to reduce the rotational driving force (driving torque) applied to the wheel 2.

  On the other hand, in the process of S36, if the torque detected this time is smaller than the average value, it means that the ground contact load is reduced due to the non-uniformity of the wheel 2. Therefore, in the process of S37, the wheel The wheel driving device 3 is controlled so as to increase the rotational driving force (driving torque) applied to 2.

  As a result, it is possible to reduce the fluctuation of the ground load caused by the non-uniformity (non-uniformity) of the wheel 2 and to apply unnecessary rotational driving force and suppress slip loss. It can be transmitted efficiently to the road surface, and fuel efficiency can be improved accordingly.

  Here, in the flowchart (wheel control process) shown in FIG. 4, the process of S7 is performed as the driving force adjusting means according to claim 1, and the process of S1 is performed as the phase acquiring means according to claim 2. The process of S2 corresponds to the speed acquisition means, and the process of S5 corresponds to the speed dependence adjustment ratio acquisition means. Moreover, in the flowchart (wheel control process) shown in FIG. 9, the process of S37 corresponds to the driving force adjusting means according to claim 1.

  Further, in the flowchart (map creation process) shown in FIG. 7, the process of S24 corresponds to the fluctuation acquisition means according to claim 4, and the process of S27 corresponds to the adjustment ratio generation means.

  The present invention has been described above based on the embodiments. However, the present invention is not limited to the above embodiments, and various improvements and modifications can be made without departing from the spirit of the present invention. It can be easily guessed.

  For example, the numerical values given in the above embodiments are merely examples, and other numerical values can naturally be adopted.

  Although description is omitted in the first embodiment, the contents of the rotation angle torque correction map 72a and the speed torque correction map 72b stored in the EEPROM 72 may be changeable. Specifically, when a wheel 2 (tire, wheel) is newly replaced, characteristics unique to the wheel 2 (that is, the rotational angle torque correction map 72a and the speed torque correction map 72b actually measured for the wheel 2), The rotational angle torque correction map 72a and the speed torque correction map 72b already stored in the EEPROM 72 may be overwritten (replaced).

  In the second embodiment, the case where the rotational angle torque correction map 273a and the speed torque correction map 273b are provided in the ROM 273 has been described. However, the present invention is not limited to this, and the EEPROM 72 (see FIG. 2), and the EEPROM 72 may be provided with a rotation angle torque correction map 273a and a speed torque correction map 273b. Thereby, it is not necessary to execute the map creation process every time the engine is started.

  In the second embodiment, after the rotation angle torque correction map 273a and the speed torque correction map 273b are created, the case where the contents are maintained until the power of the vehicle control device 200 is turned off has been described. However, the present invention is not limited to this, and the contents of the rotation angle torque correction map 273a and the speed torque correction map 273b may be updated during traveling (the map creation process is re-executed). For example, the re-execution of the map creation process is performed when the travel distance of the vehicle 1 reaches a predetermined distance, when the air pressure of the wheels 2 fluctuates, or when the driver gives an instruction. .

  In the second embodiment, the case where the rotation angle torque correction map 273a and the speed torque correction map 273b are not created in the map creation process (S21: No) has been described. However, the present invention is not necessarily limited to this, and the processing after S22 may be executed only when it is determined that a predetermined condition is satisfied.

  Here, the predetermined condition is that when the travel route of the vehicle 1 is determined to be a straight line, when the travel route of the vehicle is determined to be a flat road having a predetermined inclination angle or less, the travel route of the vehicle 1 is Examples include cases where it is determined that the vehicle is a paved road surface, cases where the vehicle 1 is determined to be traveling at a constant speed, and cases where the wind pressure received by the vehicle 1 is determined to be equal to or less than a predetermined value. A navigation system may be used for these determinations.

  You may combine the said 2nd Embodiment and 3rd Embodiment. That is, in the second embodiment, the wheel control process described in the third embodiment is executed until the rotation angle torque correction map 273a and the speed torque correction map 273b are created by the map creation process. You may comprise so that it may do. As a result, slip loss can be reduced even when the rotation angle torque correction map 273a or the like has not been created, so that fuel efficiency can be further improved.

  In the second embodiment, the case where the load sensor device 234 is used to directly detect the ground contact force of the wheel 2 has been described. However, the present invention is not necessarily limited to this. For example, each motor 3FL in the wheel drive device 3 You may comprise so that the contact force of each wheel 2 may be calculated using the torque sensor with which the drive shaft of -3RR was mounted | worn. Specifically, the ground contact force Fr of the wheel 2 is obtained by using the torque Fb detected by the torque sensor, the rotational angular acceleration ω ′ of the wheel 2, and the completion moment I of the wheel 2, Fr = Fb−ω '× I can be obtained.

  In the third embodiment, the case where the average value of torque in the latest one rotation is calculated has been described. However, the present invention is not necessarily limited to this, and the average value of torque is calculated using data of one rotation or more. It is naturally possible to calculate.

  In the third embodiment, the case where the drive torque is calculated based on the average value of the torque in the latest one rotation has been described, but the value of the command torque commanded to the wheel drive device 3 and the torque sensor are detected. You may comprise so that the rotational driving force (drive torque) provided to the wheel 2 may be calculated from the difference with the value of torque.

It is the schematic diagram which showed typically the vehicle by which the vehicle control apparatus in 1st Embodiment of this invention is mounted. It is the block diagram which showed the electric constitution of the control apparatus for vehicles. (A) is the schematic diagram which illustrated typically the content of the rotation angle torque correction map, (b) is the schematic diagram which illustrated typically the content of the speed torque correction map. It is a flowchart which shows a wheel control process. It is the schematic diagram which illustrated typically the state of the wheel which applied the wheel control process. It is the block diagram which showed the electrical structure of the vehicle control apparatus in 2nd Embodiment. It is a flowchart which shows a map creation process. It is the block diagram which showed the electric constitution of the control apparatus for vehicles in 3rd Embodiment. It is a flowchart which shows a wheel control process. It is the model which illustrated typically generation | occurrence | production of the local slip resulting from the non-uniformity of a wheel, and time passages, such as a wheel speed at the time of a wheel rotating about 4 times, are represented.

Explanation of symbols

100, 200, 300 Vehicle control device 2 Wheel 2FL, 2FR Front wheel 2RL, 2RR Rear wheel 3 Wheel drive device (drive device)
3FL-3RR FL-RR motor (part of drive unit)
72a, 273a Rotational angle torque correction map (adjustment ratio storage means)

Claims (4)

In a vehicle control device used in a vehicle including a wheel and a drive device that applies a rotational driving force to the wheel,
A driving force adjusting means for adjusting the magnitude of the rotational driving force applied to the wheel by the driving device;
The driving force adjusting means adjusts the magnitude of the rotational driving force applied to the wheel so that the fluctuation of the contact force generated due to the non-uniformity of the wheel when the wheel travels on the road surface is reduced. A vehicle control device. An adjustment ratio storage means for storing an adjustment ratio when the driving force adjusting means adjusts the magnitude of the rotational driving force applied to the wheel in association with the phase of the wheel;
Phase acquisition means for acquiring the phase of the wheel,
The driving force adjusting means reads an adjustment ratio corresponding to the phase of the wheel acquired by the phase acquiring means from the adjustment ratio storage means, and a rotational driving force applied to the wheel based on the read adjustment ratio. The vehicle control apparatus characterized by adjusting the size of the vehicle. Speed acquisition means for acquiring a vehicle speed of the vehicle;
Speed-dependent adjustment ratio acquisition means for acquiring the adjustment ratio according to the vehicle speed of the vehicle acquired by the speed acquisition means and the phase of the wheel obtained by the phase acquisition means;
The vehicle driving device according to claim 2, wherein the driving force adjusting means adjusts the magnitude of the rotational driving force applied to the wheel based on the adjustment ratio acquired by the speed-dependent adjustment ratio acquisition. Control device. Fluctuation acquisition means for acquiring fluctuations in contact force generated due to non-uniformity of the wheels when the wheels travel on the road surface;
Adjustment rate generation means for generating the adjustment rate based on the change in the contact force acquired by the change acquisition means,
The adjustment ratio generated by the adjustment ratio generation means is stored in the adjustment ratio storage means, and the change of the ground contact force is acquired by the change acquisition means while the vehicle is running. The vehicle control device according to claim 2 or 3.

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