JP5299047B2 - Travel control device - Google Patents

Description

  The present invention relates to a travel control device that travels on a road having a low friction region having a road surface resistance smaller than that of the surrounding area on a travel road.

  Various techniques for controlling a travel route according to a road surface condition are disclosed.

  For example, Patent Document 1 discloses a technique related to traveling control when traveling on a traveling path with a puddle. According to this travel control device, when the position of a puddle on the road is detected, if there is no other vehicle around the own vehicle, control is performed to avoid the puddle, and there is another vehicle around the own vehicle. Is controlled to decelerate.

JP 2008-179251 A

  However, in the above-described conventional travel control device, there is a case where the puddle cannot be completely avoided due to the relationship with the positions of other vehicles around the host vehicle. For this reason, when the frictional resistance with respect to the wheels on the traveling road surface such as a puddle passes through a region where the friction resistance is smaller than the surroundings, there is a possibility that the vehicle cannot be controlled properly in a stable state.

  An object of the present invention is to control the traveling of a vehicle so that the vehicle can be maintained in a stable state when traveling on a traveling road having a low friction region in which the frictional resistance against wheels is smaller than that of the surroundings on the traveling road surface. The object is to provide a travel control device.

The travel control device according to the present invention includes a low friction region acquisition means for acquiring a low friction region that is a region where the frictional resistance with respect to the wheels of the vehicle is smaller than the surroundings on the traveling road surface, and the length of the low friction region in the vehicle width direction The vehicle passes through the low friction region based on the region width acquisition means for acquiring the position, the position of the low friction region with respect to the vehicle, the width in the width direction of the low friction region, and the length between the left and right wheels in the vehicle. If it is determined that the vehicle cannot be avoided, the vehicle travel path is controlled so that the vehicle passes over the low friction region, and only one of the left and right wheels of the vehicle does not enter the low friction region. And a travel control means for controlling the travel route of the vehicle.

  According to such a travel control device, the left and right wheels of the vehicle do not come into contact with road surfaces having different friction coefficients. For example, the stability of the vehicle is improved by a yaw moment generated by a difference in braking force between the left and right wheels. It is possible to avoid the possibility that the performance is impaired. As a result, the difference in friction between the two wheels can be eliminated when traveling on a road having a low friction region where the frictional resistance against the wheels of the vehicle is small compared to the surroundings, so that the vehicle can be maintained in a stable state. Is possible.

  In the travel control device of the present invention, when it is determined that the low friction region can be avoided, the travel control unit may control the travel route of the vehicle so as to avoid the low friction region. Thereby, it is possible to completely avoid the vehicle entering the low friction region. As a result, it is possible to prevent the left and right wheels of the vehicle from entering the low friction region and to travel in the high friction region with both wheels, so that the vehicle can be maintained in a stable state.

  In the travel control device of the present invention, the travel control means determines that the low friction region cannot be avoided, and the length between the left and right wheels in the vehicle is longer than the length in the width direction of the low friction region. If determined, the travel route of the vehicle may be controlled such that the low friction region passes between the left and right wheels of the vehicle. Thereby, even if the vehicle cannot completely avoid the low friction region and the vehicle body may pass over the low friction region, both the left and right wheels of the vehicle are prevented from entering the low friction region, Since both wheels can travel in the high friction region, the vehicle can be maintained in a stable state.

  In the travel control device of the present invention, the travel control means determines that the low friction region cannot be avoided, and the length between the left and right wheels in the vehicle is shorter than the length in the width direction of the low friction region. When the determination is made, the travel route of the vehicle may be controlled such that the left and right wheels of the vehicle pass through the low friction region. This prevents the vehicle from completely avoiding the low friction area, and even if the vehicle body passes over the low friction area, the left and right wheels of the vehicle are prevented from entering different friction areas, Since the difference in friction between the two wheels can be eliminated, the vehicle can be maintained in a stable state.

ADVANTAGE OF THE INVENTION According to this invention, a vehicle can be maintained in the stable state, when drive | working the driving | running route with a low friction area | region where the frictional resistance with respect to the wheel of a vehicle is small compared with the circumference | surroundings.

It is the block diagram which showed the function structure of the traveling control apparatus which concerns on one Embodiment of this invention. It is a schematic block diagram which shows the traveling control apparatus of FIG. It is the flowchart which showed the traveling control of the traveling control apparatus of FIG. It is a figure explaining the traveling control shown in FIG. It is a figure explaining the traveling control shown in FIG. It is a figure explaining the traveling control shown in FIG. It is a figure explaining the traveling control shown in FIG. It is a figure explaining the traveling control shown in FIG. It is a figure explaining the traveling control shown in FIG.

  Hereinafter, a travel control device 1 according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram showing a functional configuration of a travel control device 1 according to the present invention. FIG. 2 is a schematic configuration diagram showing the travel control device 1 according to the present invention.

  As shown in FIGS. 1 and 2, the traveling control device 1 includes a forward monitoring sensor 11, a road-vehicle communication device 12, a vehicle-to-vehicle communication device 13, a GPS (Global Positioning System) receiver 14, and map information. Storage unit 15, navigation ECU (Electronic Control Unit) 16, yaw / G sensor 17, speed sensor 18, vehicle control ECU (Electronic Control Unit) 19, brake actuator 21, steering actuator 22, engine control ECU (Electronic Control Unit) 23.

  As shown in FIG. 2, the forward monitoring sensor (low friction area acquisition means, area width acquisition means) 11 is disposed on the front surface of the host vehicle 100, and the wheels of the host vehicle 100 are on the road surface in front of the host vehicle 100. The positions of the low μ region (low friction region) A and the low μ region A, which are regions where the frictional resistance with respect to is smaller than the surroundings, are acquired. The forward monitoring sensor 11 is realized by a radar, a camera, or the like. Further, the front monitoring sensor 11 acquires the width direction (left-right direction) length of the host vehicle 100 in the low μ region A. The front monitoring sensor 11 sends the acquired position information and width direction length information of the low μ region A to the vehicle control ECU 19. In the low μ region A, there are an iron plate for road construction, a manhole, an ice burn, a water pool, and the like.

  The road-to-vehicle communication device (low friction area acquisition means, area width acquisition means) 12 acquires information on the low μ area A from an optical beacon installed on the road. The optical beacon transmits information in the form of infrared communication.

  The inter-vehicle communication device (low friction area acquisition means, area width acquisition means) 13 acquires information on the low μ area A acquired by another vehicle via wireless communication.

  The GPS receiver 14 receives a radio signal including satellite orbit and time data from a GPS satellite. The GPS receiver 14 sends the received radio signal to the navigation ECU 16.

  The map information storage unit 15 stores information regarding road maps.

  The navigation ECU 16 calculates the radio signal transmitted from the GPS receiver 14 and periodically specifies the current position of the host vehicle 100. And navigation ECU16 reads the information regarding a road map from the map information storage part 15 timely, and sends out the present position information of the own vehicle 100 to vehicle control ECU19.

  The yaw / G sensor 17 detects gravity in the left-right direction in the traveling direction and gravity in the front-rear direction in the traveling direction. The yaw / G sensor 17 sends the detected gravity information to the vehicle control ECU 19.

  The speed sensor 18 detects the speed of the host vehicle 100. The speed sensor 18 sends the detected speed information to the vehicle control ECU 19.

  The vehicle control ECU (running control means) 19 determines the position of the low μ region A relative to the host vehicle 100, the width L1 of the low μ region A in the width direction, and the length L2 between the left and right wheels in the host vehicle 100. Based on this, the traveling route R of the host vehicle is controlled so that only one of the left and right wheels of the host vehicle 100 does not enter the low μ region A. The vehicle control ECU 19 includes a CPU, a ROM, a RAM, an input / output interface, and the like (not shown). The traveling control by the traveling control device 1 is realized by, for example, a program stored in the ROM being developed on the RAM by the CPU and controlling the brake actuator 21, the steering actuator 22, and the engine control ECU 23.

  The brake actuator 21 is an actuator that adjusts the brake hydraulic pressure of a wheel cylinder (not shown) of each wheel. The brake actuator 21 operates according to the target hydraulic pressure signal from the vehicle control ECU 19 and adjusts the brake hydraulic pressure of the wheel cylinder.

  The steering actuator 22 is an actuator that applies a steering torque for assisting a driver's steering operation in an electric power steering apparatus (not shown). The steering actuator 22 operates in response to a steering torque control signal from the vehicle control ECU 19 and applies steering torque to the electric power steering device.

  The engine control ECU 23 is a control device that controls the engine. The engine control ECU 23 operates in accordance with the target acceleration from the vehicle control ECU 19, sets a target opening of a throttle valve (not shown) necessary to reach the target acceleration, and sets the target opening to the target throttle opening. This is transmitted as a degree signal to a throttle actuator (not shown).

  Next, the traveling control of the traveling control device 1 will be described with reference to FIG.

  FIG. 3 is a flowchart showing a flow of characteristic processing executed by the traveling control device 1.

  First, the vehicle control ECU 19 acquires the position information of the low μ region A and the length L1 information in the width direction from the front monitoring sensor 11 (S01). The vehicle control ECU 19 also provides rainfall information and construction information that can be acquired by the road-to-vehicle communication device 12, skidding information that can be acquired by the vehicle-to-vehicle communication device 13, rainfall information that is acquired from the raindrop sensor, and the like. By using this, position information of the low μ region A and length L1 information in the width direction can be acquired.

  Next, the navigation ECU 16 calculates the radio wave signal transmitted from the GPS receiver 14 and acquires the current position of the host vehicle 100 (S02).

  Next, the vehicle control ECU 19 acquires information on the road map from the map information storage unit 15 (S03), and the low μ region A acquired in the forward monitoring sensor 11, the road-to-vehicle communication device 12, and the vehicle-to-vehicle communication device 13. Is mapped to the road map.

  Next, the vehicle control ECU 19 determines whether or not there is a low μ region A ahead of the traveling direction of the host vehicle 100 based on the mapped result (S04). Here, if the vehicle control ECU 19 determines that there is no low μ region A (S04: None), the vehicle control ECU 19 does not require control to avoid the low μ region A, and thus continues normal travel. Next, the host vehicle 100 is controlled (S12).

  On the other hand, when the vehicle control ECU 19 determines that there is the low μ region A (S04: present), the vehicle control ECU 19 determines the position of the host vehicle 100, the speed of the host vehicle 100, and the own vehicle 100 and the low μ region A. Based on the distance, it is determined whether or not the host vehicle 100 can avoid the low μ region A. For example, the vehicle control ECU 19 determines whether it cannot be avoided in the same lane or whether it cannot be avoided by changing the lane. Note that “the host vehicle 100 avoids the low μ region A” means that the host vehicle 100 completely passes through the low μ region A as shown in FIG.

  Here, when the vehicle control ECU 19 determines that the low μ region A can be avoided (S05: YES), the vehicle control ECU 19 sets the vehicle 100 so as to avoid the low μ region A as shown in FIG. The travel route R is controlled (S11). Specifically, the vehicle control ECU 19 controls the travel route R of the host vehicle 100 by controlling the brake actuator 21, the steering actuator 22, and the engine control ECU 23.

  On the other hand, when the vehicle control ECU 19 determines that the low μ region A cannot be avoided (S05: NO), the vehicle control ECU 19 adjusts the position in the width direction, and the vehicle 100 is in a split state by the low μ region A. It is determined whether or not it can be avoided (S06). For example, the vehicle control ECU 19 determines whether or not the host vehicle 100 can avoid the split state based on the travel lane width, the speed of the host vehicle 100, the distance between the host vehicle 100 and the low μ region A, and the like. . The split state means that the left and right wheels of the host vehicle 100 are in contact with road surfaces having different friction coefficients.

  Here, when the vehicle control ECU 19 determines that the host vehicle 100 can be prevented from being split by adjusting the position in the width direction (S06: YES), the vehicle control ECU 19 determines whether the vehicle control ECU 19 It is determined whether or not the length L2 between the wheels is longer than the length L1 in the width direction of the low μ region A (S07).

  Here, when the vehicle control ECU 19 determines that the length L2 between the left and right wheels in the host vehicle 100 is longer than the length L1 in the width direction of the low μ region A (S07: YES), the vehicle control ECU 19 As shown in FIG. 5, the travel route R of the host vehicle 100 is controlled so that the low μ region A passes between the left and right wheels of the host vehicle 100 (S10). In other words, when the left and right wheels of the host vehicle 100 straddle the low μ region A, the left and right wheels of the host vehicle 100 are prevented from entering the low μ region A. As a result, even if the host vehicle 100 cannot completely avoid the low μ region A and the vehicle body of the host vehicle 100 passes over the low μ region A, both the left and right wheels of the host vehicle 100 are low. Since the vehicle can be prevented from entering the μ region A and both wheels can travel in the high friction region, the host vehicle 100 can be maintained in a stable state.

  On the other hand, when the vehicle control ECU 19 determines that the length L2 between the left and right wheels of the host vehicle 100 is equal to or less than the length L1 in the width direction of the low μ region A (S07: NO), the vehicle control ECU 19 As shown in FIG. 5, the travel route R of the host vehicle 100 is controlled so that both the left and right wheels of the host vehicle 100 pass through the low μ region A (S09). Thus, even when the host vehicle 100 cannot completely avoid the low μ region A and the vehicle body of the host vehicle 100 passes over the low μ region A, one of the left and right wheels of the host vehicle 100 is Since entering into the low μ region A can be prevented and the difference in friction between the two wheels can be eliminated, it is possible to avoid the behavior of the host vehicle 100 becoming unstable.

  If the vehicle control ECU 19 determines in step S06 that it cannot be avoided that the host vehicle 100 is in a split state due to the low μ region A, the vehicle control ECU 19 applies the following addition to the host vehicle 100. Deceleration / steering suppression control is performed (S08).

  That is, as shown in FIG. 7, the vehicle control ECU 19 determines that there is a sufficient distance L3 between the low μ region A and the other vehicle 101 located in front of the low μ region A, or as shown in FIG. As described above, when the other vehicle 101 in front of the low μ region A is traveling and the distance L4 between the low μ region A and the other vehicle 101 is expected to be sufficiently secured, the low μ region A is The own vehicle 100 is controlled to pass. Further, the vehicle control ECU 19 performs control so that the host vehicle 100 does not perform acceleration / deceleration while passing through the low μ region A. Thereby, even when the host vehicle 100 travels in the low μ region A, the host vehicle 100 can be maintained in a stable state.

On the other hand, when the vehicle control ECU 19 determines that the distance L5 between the low μ region A and the other vehicle 101 located in front of the low μ region A cannot be sufficiently secured, as shown in FIG. The host vehicle 100 is controlled to stop before this. Specifically, the vehicle control ECU 19 sets the speed of the other vehicle 101 positioned in front of the low μ region A to V, the assumed maximum deceleration of the other vehicle 101 to a, the speed of the host vehicle 100 to U, and the host vehicle. When the assumed minimum deceleration of 100 is b and the distance between the low μ region A and the host vehicle 100 is 1, the front of the low μ region A is satisfied when the condition of l + V ² / 2a <U ² / 2b is satisfied. The host vehicle 100 is controlled to stop. As a result, the behavior of the host vehicle 100 becomes unstable in the low μ region A, and the other vehicle 101 in front of the low μ region A can be prevented from contacting.

  As described above, according to the traveling control device 1 of the present embodiment, the left and right wheels of the host vehicle 100 do not come into contact with road surfaces having different friction coefficients. For this reason, it is possible to avoid the possibility that the stability of the host vehicle 100 is impaired due to a yaw moment or the like generated by a difference in braking force between the left and right wheels. As a result, the host vehicle 100 can be maintained in a stable state when traveling on a road surface with the low μ region A.

  As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the meaning of invention.

  DESCRIPTION OF SYMBOLS 1 ... Traveling control apparatus, 11 ... Front monitoring sensor, 12 ... Road-to-vehicle communication machine, 13 ... Inter-vehicle communication machine, 14 ... GPS receiver, 15 ... Map information storage part, 16 ... Navigation ECU, 17 ... Yaw / G Sensor, 18 ... Speed sensor, 19 ... Vehicle control ECU, 21 ... Brake actuator, 22 ... Steering actuator, 23 ... Engine control ECU, 100 ... Own vehicle, 101 ... Other vehicle, A ... Low-μ region, L1 ... Vehicle width direction Length, L2: Length in the low μ region width direction, L3: Distance, L4 ... Distance, L5 ... Distance, R ... Traveling route.

Claims (3)

A low friction region acquisition means for acquiring a low friction region in which the frictional resistance against the wheels of the vehicle is small compared to the surroundings on the road surface;
Area width acquisition means for acquiring the length of the vehicle in the width direction of the low friction area;
Based on the position of the low friction region with respect to the vehicle, the length in the width direction of the low friction region, and the length between the left and right wheels in the vehicle , the vehicle is prevented from passing through the low friction region. When it is determined that the vehicle cannot be used, the vehicle travel path is controlled so that the vehicle passes over the low friction region, and only one of the left and right wheels of the vehicle enters the low friction region. Travel control means for controlling the travel route of the vehicle so that there is no
A travel control device comprising: When the traveling control means determines that the low friction region cannot be avoided and determines that the length between the left and right wheels in the vehicle is longer than the width of the low friction region in the width direction, Controlling the travel path of the vehicle so that a low friction region passes between the left and right wheels of the vehicle;
The travel control device according to claim 1. When the travel control means determines that the low friction region cannot be avoided and determines that the length between the left and right wheels in the vehicle is shorter than the width direction length of the low friction region, Controlling the travel route of the vehicle so that the left and right wheels of the vehicle pass through the low friction region;
The travel control device according to claim 1.

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