Control device

Abstract

To provide a control device which can improve energy consumption at the time of vehicle travel while suppressing increase of number of sensors.SOLUTION: A control device can acquire information of vehicle travel position and information of vehicle output at the travel position. The control device controls the vehicle travel position based on the information of the travel position and the vehicle output which are acquired while the vehicle travel position is changed.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a control device. [Background technology]

[0002] 2. Description of the Related Art Conventionally, a platoon driving system in which a plurality of vehicles travel in a platoon is known (see, for example, Patent Document 1).

[0003] The vehicle platoon system in Patent Document 1 is configured to organize a platoon so as to reduce the overall energy consumption of the platoon. Specifically, the vehicle platoon system is configured to determine the basic shape of the platoon based on the wind direction. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2009-157790 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, the above-mentioned conventional technology requires a wind direction sensor or the like for detecting the wind direction around the vehicle, which increases the number of sensors to be installed in the vehicle.

[0006] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a control device that can improve energy consumption when the vehicle is running while suppressing an increase in the number of sensors. [Means for solving the problem]

[0007] The control device according to the present invention comprises: In a following control in which the vehicle automatically follows the preceding vehicle while maintaining a predetermined distance, the vehicle's running is controlled by the following method. It is to control During the following control, the relative position of the host vehicle in the left-right direction with respect to the preceding vehicle is changed, and the changing relative position is acquired as information regarding the traveling position. A traveling position acquisition unit; During the following control, the energy consumption of the host vehicle required to follow the preceding vehicle in a traveling state at each of the traveling positions is acquired as information related to the output of the host vehicle. An output acquisition unit; The information regarding each of the traveling positions that is acquired and the information regarding the output of the host vehicle at each of the traveling positions are stored in association with each other, and the traveling position where the energy consumption required for the host vehicle to follow the preceding vehicle is the smallest is determined as an optimal traveling position, and the and a travel position control unit that controls the travel position.

[0008] With this configuration, a driving position where the output of the vehicle is reduced is searched for and the driving position is determined, thereby improving the energy consumption while the vehicle is traveling while suppressing an increase in the number of sensors. In other words, a driving position where the air resistance is low can be selected without knowing the wind direction. Effect of the Invention

[0009] According to the control device of the present invention, it is possible to improve energy consumption during vehicle running while suppressing an increase in the number of sensors. [Brief description of the drawings]

[0010] [Figure 1] 1 is a block diagram showing an electric vehicle equipped with a control device according to an embodiment of the present invention. [Diagram 2] 4 is a flowchart for explaining a search operation for a traveling position in the electric vehicle of FIG. [Diagram 3] FIG. 11 is a schematic diagram for explaining a hybrid vehicle according to a modified example of the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, one embodiment of the present invention will be described.

[0012] First, with reference to FIG. 1, the configuration of an electric vehicle 100 equipped with a control device 6 according to an embodiment of the present invention will be described.

[0013] The electric vehicle 100 has an automatic driving function and is configured to be able to run automatically without the operation of a passenger. As shown in Fig. 1, the electric vehicle 100 includes a motor 1, a PCU (power control unit) 2, a battery 3, a braking device 4, a steering device 5, a control device 6, a GPS receiver 7, and a surrounding information acquisition device 8. The electric vehicle 100 is an example of the "vehicle" of the present invention.

[0014] The motor 1 is provided to output a driving force for running the vehicle. The PCU 2 has an inverter and the like, and is configured to control the motor 1. The battery 3 is chargeable and dischargeable, and is configured to store power for driving the motor 1. The brake device 4 is provided to output a braking force. The steering device 5 is provided to adjust the steering angle of the wheels (not shown).

[0015] The GPS receiver 7 is configured to be able to receive signals from GPS satellites (not shown) and calculate the current location. The surrounding information acquisition device 8 is configured to acquire information about the surroundings of the electric vehicle 100. For example, the surrounding information acquisition device 8 includes a camera and a radar (not shown), and is configured to capture images of the surroundings of the electric vehicle 100 and detect objects in the surroundings of the electric vehicle 100.

[0016] The control device 6 includes a calculation unit and a storage unit (not shown), and is configured to control the electric vehicle 100 by executing a program stored in the storage unit by the calculation unit. For example, the control device 6 is configured to control the PCU 2, the brake device 4, and the steering device 5 based on inputs from the GPS receiver 7 and the surrounding information acquisition device 8, etc.

[0017] Specifically, the control device 6 is configured to be capable of performing automatic driving including following control. During following control, the control device 6 controls the PCU 2, the brake device 4, and the steering device 5 so that the electric vehicle 100 automatically follows (follows) a preceding vehicle (not shown) while maintaining a predetermined distance therebetween.

[0018] The control device 6 is configured to search for an optimal driving position in the left-right direction of the vehicle relative to the preceding vehicle during tracking control, and move the vehicle to the optimal driving position. The optimal driving position is, for example, a position where air resistance is low, making it possible to improve energy consumption during vehicle driving. The control device 6 is capable of acquiring information on the driving position and information on the vehicle output (output of the motor 1), and is configured to control the driving position of the electric vehicle 100 based on the information on the driving position and information on the vehicle output acquired while changing the driving position of the electric vehicle 100. The "driving position acquisition unit", "output acquisition unit" and "driving position control unit" of the present invention are realized by the program stored in the storage unit being executed by the calculation unit.

[0019] Further, the control device 6 is connected to a switch 9, a current sensor 3a, and a voltage sensor 3b. The switch 9 is provided for an occupant to instruct the start of a search for an optimal driving position during tracking control. The current sensor 3a is provided for detecting a charging / discharging current of the battery 3, and the voltage sensor 3b is provided for detecting a voltage of the battery 3. The control device 6 is capable of calculating a vehicle output (energy consumption) based on the detection results of the current sensor 3a and the voltage sensor 3b. The control device 6 is also configured to be capable of calculating a driving position of the host vehicle relative to the preceding vehicle based on, for example, an input from the surrounding information acquisition device 8.

[0020] -Searching for driving position- Next, a search operation for a traveling position of the electric vehicle 100 of this embodiment will be described with reference to Fig. 2. This search operation for a traveling position is performed during following control. That is, it is performed when the electric vehicle 100 is automatically following a preceding vehicle while maintaining a predetermined distance therebetween. Note that the following steps are executed by the control device 6.

[0021] First, in step S1 of Fig. 2, it is determined whether the switch 9 has been operated. That is, it is determined whether an instruction to start searching for the traveling position by the occupant has been accepted. If it is determined that the switch 9 has been operated, the process proceeds to step S2. On the other hand, if it is determined that the switch 9 has not been operated, step S1 is repeated. That is, the process waits until the switch 9 is operated.

[0022] Next, in step S2, it is determined whether or not the electric vehicle 100 following the preceding vehicle can be moved in the left-right direction. Whether or not it can be moved in the left-right direction is determined, for example, based on an input from the surrounding information acquisition device 8. Then, if it is determined that the electric vehicle 100 can be moved in the left-right direction, a movable range is calculated and the process proceeds to step S3. On the other hand, if it is determined that the electric vehicle 100 cannot be moved in the left-right direction, the process proceeds to END. That is, the search for a traveling position is not performed, and following at the current traveling position is continued.

[0023] Next, in step S3, the steering device 5 is controlled to move the electric vehicle 100 to one end (for example, the right end) of the movable range. Then, for example, the position of the electric vehicle 100 after the movement relative to the preceding vehicle is acquired as information related to the traveling position. Next, in step S4, the vehicle output at this traveling position is calculated. The vehicle output is calculated, for example, based on the detection results of the current sensor 3a and the voltage sensor 3b. That is, information related to the vehicle output is acquired. Furthermore, the information related to the traveling position and the information related to the vehicle output at that traveling position are stored in the storage unit in association with each other.

[0024] Next, in step S5, the steering device 5 is controlled to move the electric vehicle 100 a predetermined distance toward the other end (e.g., the left end) of the movable range. This predetermined distance is, for example, a distance calculated based on the movable range, and is set so that the electric vehicle 100 reaches the other end of the movable range when the movement of the predetermined distance is repeated a predetermined number of times. Then, for example, the position of the electric vehicle 100 after the movement relative to the preceding vehicle is acquired as information on the traveling position. Next, in step S6, the vehicle output at this traveling position is calculated. The vehicle output is calculated based on, for example, the detection results of the current sensor 3a and the voltage sensor 3b. That is, information on the vehicle output is acquired. Furthermore, the information on the traveling position and the information on the vehicle output at the traveling position are stored in the storage unit in association with each other.

[0025] Next, in step S7, it is determined whether the electric vehicle 100 has reached the other end of the movable range. If it is determined that the electric vehicle 100 has reached the other end, the process proceeds to step S8. On the other hand, if it is determined that the electric vehicle 100 has not reached the other end, the process returns to step S5. That is, steps S5 and S6 are repeated until the electric vehicle 100 reaches the other end of the movable range. In this way, information related to the traveling position and information related to the vehicle output are acquired while the electric vehicle 100 is moved a predetermined distance within the movable range.

[0026] Next, in step S8, an optimal driving position for the electric vehicle 100 is determined. For example, a driving position where the vehicle output is the smallest is determined as the optimal driving position. In other words, a driving position where the energy required to follow the preceding vehicle is the smallest is determined as the optimal driving position. Specifically, information related to the vehicle output stored in the storage unit is compared, and the driving position where the information related to the smallest vehicle output is obtained is selected as the optimal driving position.

[0027] Next, in step S9, the steering device 5 is controlled to move the electric vehicle 100 to the determined optimum driving position. At this time, the electric vehicle 100 is moved using information about the driving position associated with information about the smallest vehicle output.

[0028] -effect- In this embodiment, as described above, the optimum driving position of the vehicle in the left-right direction relative to the preceding vehicle is searched for during tracking control, and the driving position of the electric vehicle 100 is determined to be the optimum driving position, thereby improving the energy consumption during vehicle driving while suppressing an increase in the number of sensors. In other words, a driving position that reduces air resistance can be selected without knowing the wind direction.

[0029] -Other embodiments- It should be noted that the embodiments disclosed herein are illustrative in all respects and are not intended to be limiting. Therefore, the technical scope of the present invention is not interpreted solely by the above-described embodiments, but is defined by the claims. The technical scope of the present invention includes all modifications within the scope and meaning equivalent to the claims.

[0030] For example, in the above embodiment, an example was shown in which a driving position where air resistance is low is searched for based on the vehicle output during tracking control, but this is not limited to this, and a driving position where rolling resistance is low may be searched for based on the vehicle output.

[0031] In the above embodiment, the present invention is applied to the electric vehicle 100, but the present invention may be applied to a hybrid vehicle. In this case, the vehicle output can be calculated by adding the output of the motor and the output of the internal combustion engine. The output of the motor is calculated based on the charging and discharging current and voltage of the battery. The output of the internal combustion engine is calculated based on the rotation speed and torque of the internal combustion engine. The hybrid vehicle may not have a function of charging the battery using an external power source, or may have a function of charging the battery using an external power source.

[0032] Here, in a hybrid vehicle 200 according to a modified example shown in Fig. 3, it is possible to calculate the torque of an internal combustion engine 201 based on the torque of a generator 202. This hybrid vehicle 200 includes an internal combustion engine 201, a generator 202, a motor 203, a power split mechanism 204, and a countershaft 205. The hybrid vehicle 200 is an example of the "vehicle" of the present invention.

[0033] The internal combustion engine 201 is configured to burn fuel to output driving force for running the vehicle. The generator 202 functions mainly as a power generator, and also functions as an electric motor depending on the situation. The motor 203 functions mainly as an electric motor, and also functions as a generator depending on the situation. The motor 203 is capable of outputting driving force for running the vehicle, and a motor-side drive gear 203a is provided on the output shaft.

[0034] The power split mechanism 204 is, for example, a planetary gear mechanism, and is configured to split the output of the internal combustion engine 201 into power for driving drive wheels (not shown) and power for driving the generator 202 to generate electricity. Specifically, the power split mechanism 204 has a sun gear 204S of an external gear that rotates at the center of multiple gear elements, a pinion gear 204P of an external gear that rotates and revolves around the sun gear 204S while circumscribing (meshing) with the sun gear 204S, a ring gear 204R of an internal gear formed in a hollow annular shape so as to mesh with the pinion gear 204P, and a planetary carrier 204C that supports the pinion gear 204P and rotates through the revolution of the pinion gear 204P. The planetary carrier 204C is connected to the output shaft of the internal combustion engine 201 via a damper. The sun gear 204S is connected to the output shaft of the generator 202. The ring gear 204R is provided with an engine side drive gear 204a.

[0035] A counter driven gear 205a is provided on the counter shaft 205, and an engine side drive gear 204a and a motor side drive gear 203a mesh with the counter driven gear 205a. Drive wheels are connected to the counter shaft 205 via a differential device (not shown).

[0036] In such a hybrid vehicle 200, the relationship of the following equation (1) holds in a steady state.

[0037] Te = ((1 + ρ) / ρ) × Tg (1) In equation (1), Te is the torque of the internal combustion engine 201, Tg is the torque of the generator 202, and ρ is the planetary gear ratio (number of sun gear teeth / number of ring gear teeth).

[0038] Therefore, as described above, in the hybrid vehicle 200, the torque of the internal combustion engine 201 can be calculated based on the torque of the generator 202.

[0039] The present invention may also be applied to conventional vehicles. In this case, the vehicle output may be predicted based on the fuel consumption.

[0040] In addition, in the above embodiment, an example is shown in which a search for the traveling position is started using switch 9, but this is not limited to the above. A search for the traveling position may be started when tracking control is started, or a search for the traveling position may be started when the vehicle output increases and exceeds a predetermined value.

[0041] In addition, in the above embodiment, an example is shown in which the optimal driving position is determined after searching the movable range, but this is not limited to the above. The electric vehicle may be moved and the vehicle output before and after the move may be compared, and this (moving the electric vehicle and comparing the vehicle output before and after the move) may be repeated while the vehicle output is decreasing, and when the vehicle output increases, the driving position immediately before that (before the move) may be determined to be the optimal driving position.

[0042] In the above embodiment, the predetermined distance in step S5 is calculated based on the movable range, but the present invention is not limited to this. The predetermined distance in step S5 may be a distance that is set in advance. [Industrial Applicability]

[0043] The present invention can be used in a control device for controlling a vehicle. [Explanation of symbols]

[0044] 6. Control device 100 Electric vehicles (vehicles) 200 Hybrid vehicles (vehicles)

Claims

[Claim 1] A control device for controlling travel of a host vehicle in a following control in which the host vehicle automatically follows a preceding vehicle while maintaining a predetermined distance therebetween, a traveling position acquisition unit that changes a relative position of the host vehicle with respect to the preceding vehicle in a left-right direction during the following control and acquires the changing relative position as information related to the traveling position; an output acquisition unit that acquires, as information related to an output of the host vehicle, energy consumption of the host vehicle that is required for following the preceding vehicle in a traveling state at each of the traveling positions during the following control; a driving position control unit that associates and stores information about each of the acquired driving positions with information about the output of the vehicle at each driving position, determines among the driving positions the driving position at which the energy consumption required for the vehicle to follow the preceding vehicle is the smallest as an optimal driving position, and controls the driving position of the vehicle.

Images