JP6495076B2 - Reverse drive assist device for connected vehicles - Google Patents

Description

  The present invention acquires (detects) a connection angle of a connected vehicle such as a tractor (towing vehicle) and a trailer (towed vehicle) to be pulled by the tractor, and uses the acquired (detected) connection angle to move the connected vehicle backward. It relates to technology that supports driving.

  Conventionally, there is a connected vehicle in which a tractor (towing vehicle) with power is connected to a trailer (towed vehicle) so as to be rotatable around a substantially vertical pivot (note that the connection is configured to be detachable). Many).

  By the way, because it is desired to improve transportation efficiency due to lack of drivers, etc., instead of trucks etc. in which a power source such as an engine and a loaded part of a transported item (luggage) are integrated, The use of a connected vehicle in which a tractor (towed vehicle) provided and a trailer (towed vehicle) for loading an object to be transported are detachably connected is expected.

  In other words, in a situation where there is a shortage of drivers, the driver pulls a trailer loaded with objects to a certain destination on a specific tractor, and then disconnects the trailer from the tractor. It is envisaged that the form of transportation such as connecting another trailer (towed vehicle) loaded with the next object to be transported to the tractor and transporting the object to be transported to another place will be expanded.

  However, on the other hand, a connected vehicle with a trailer connected to a tractor is difficult to drive, and the driver is required to have experience and skill (especially the reverse is more difficult for a driver who has little experience). Since it takes time to cultivate, even if the transportation form changes, it is still difficult to solve the shortage of skilled drivers.

For this reason, a system that supports driving of a connected vehicle has also been proposed.
For example, Patent Document 1 describes a system that supports driving of a connected vehicle by displaying an expected movement trajectory of a trailer.

  Specifically, the connected vehicle driving support system of Patent Document 1 installs a camera on the trailer side of a connected vehicle including a tractor and a trailer, and the camera captures the back of the trailer. The driving support system converts each photographed image into a bird's eye view image by projecting each photographed image on bird's eye view coordinates parallel to the road surface, while deriving the optical flow of a moving image composed of a plurality of photographed images on the bird's eye view coordinates. Then, the connection angle between the tractor and the trailer is estimated from the optical flow and the movement information of the tractor, and the trailer movement predicted locus is derived from the connection angle and the movement information of the tractor. And it is comprised so that the image which superimposed this movement prediction locus | trajectory on the bird's-eye view image may be output to a display apparatus.

  Further, Patent Document 2 discloses a vehicle backward driving support device for towing a to-be-triggered object, a first image photographed by a first photographing means (camera) provided at the rear of the vehicle, and a to-be-triggered object. And the second image captured by the second imaging means (camera) provided behind the vehicle, the relative positional relationship between the vehicle and the to-be-towed object is extended, and the vehicle is moved according to the relative positional relationship. A description is given in which an expected movement miracle of the towed object at the time of reverse is calculated and a composite image of the second image and the expected movement miracle is displayed so as to be visible to the driver.

JP 2009-60499 A JP 2006-256544 A

  That is, as described in Patent Document 1, Patent Document 2, and the like, conventionally, information is displayed on a display device such as a monitor when the connected vehicle is reversely driven.

  However, since it is very difficult to actually drive the connected vehicle backward, it is difficult to say that it is possible to provide effective driving support because there is no room to watch the monitor because the surrounding safety is visually checked. It was a thing.

  In addition, because the tractor (tow vehicle) and trailer (towed vehicle) are bent with a connecting angle, the predicted vehicle traveling direction and the vehicle's positional relationship at the time of reverse are complicated, so they are displayed on the monitor. It is difficult to immediately grasp the current situation visually from the contents, and the current situation is that the driver's skill (skilled) is a major factor.

  The present invention has been made in view of such circumstances, and has a relatively simple and low-cost configuration, but the connecting angle is set when the connecting vehicle including the tractor (towed vehicle) and the trailer (towed vehicle) is driven backward. Providing a reverse drive support device for a connected vehicle that supports the reverse drive of the connected vehicle by providing the driver with information related to the sound as information related to voice, beep sound, sound effect, music and other sounds With the goal.

For this reason, the backward driving support device for a connected vehicle according to the present invention is:
A reverse drive assisting device for a connected vehicle comprising a tow vehicle and a towed vehicle connected rotatably around a connecting shaft extending in a substantially vertical direction with respect to the tow vehicle,
Steering angle acquisition means for acquiring the steering angle of the tow vehicle;
A connection angle acquisition means for acquiring a connection angle that is a rotation angle of a towed vehicle around a connection axis of the towed vehicle;
With
The change in the connecting angle when the vehicle is moved backward while maintaining the current steering angle is converted into information related to sound, and the information related to the sound is notified to the driver, thereby assisting the backward driving of the connected vehicle. In things,
The change in the connection angle when the vehicle is moved backward while maintaining the current steering angle is such that when the connection angle increases more than a predetermined value, when the connection angle falls within a predetermined range, the connection angle decreases more than a predetermined value. It is characterized by notifying the driver of sound information corresponding to each case .

In the present invention,
A connection angle θ, which is a rotation angle around a connection axis of the towed vehicle with respect to the towed vehicle,
δ: Actual steering angle (actual steering angle)
L1: Distance between tractor axles L2: Distance from coupling point to trailer rear axle Lh: Coupler offset (distance from coupling point to rear axle of tractor)
V1: Wheel speed of the rear wheel of the tractor (turning speed of the rear wheel shaft with respect to the turning center of the tractor)
V2: Wheel speed of the rear wheel of the trailer (the turning speed of the rear wheel shaft with respect to the turning center of the trailer)
It can be characterized by acquiring by.

  According to the present invention, the information related to the connection angle is voiced when the connected vehicle including the tractor (towed vehicle) and the trailer (towed vehicle) is driven backward while having a relatively simple and low-cost configuration. In addition, it is possible to provide a reverse drive assist device for a connected vehicle that supports the reverse drive of the connected vehicle by providing the driver with information related to beep sound, sound effect, music, and other sounds.

It is a side view which shows an example of the connection vehicle (tractor and trailer) to which the connection angle detection apparatus of the connection vehicle which concerns on one embodiment of this invention is applied. It is a top view which shows an example of the connection vehicle (tractor and trailer) to which the connection angle detection apparatus of the connection vehicle which concerns on embodiment same as the above is applied. (A) is a top view explaining the driving | operation operation | movement which gives the trigger of the turning at the reverse drive of a connection vehicle, (B) is about the drive operation in the case of keeping the connection angle of a connection vehicle constant at the reverse drive of a connection vehicle. It is a top view explaining, (C) is a top view explaining driving | operation operation which returns a steering wheel (steering) to a straight-ahead state in reverse driving | running | working of a connection vehicle. It is a figure explaining the area | region where a connection angle increases more than predetermined with respect to a steering angle, the area | region maintained substantially constant, and the area | region which decreases more than predetermined in reverse driving | running | working. It is explanatory drawing for detecting (acquiring) connection angle (theta) based on a geometric model in the connection angle detection apparatus of the connection vehicle which concerns on embodiment same as the above. (A) is a perspective view which shows one structural example of the driving assistance system of the connection vehicle which concerns on this Embodiment, (B) is a figure which shows the geometric model at the time of the low speed turn in the reverse driving | running | working of a connection vehicle.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments according to the present invention will be described with reference to the accompanying drawings. The present invention is not limited to the embodiments described below.

An embodiment of the present invention will be described with reference to the accompanying drawings.
As shown in FIGS. 1 and 2, a connected vehicle 10 according to an embodiment of the present invention includes a tractor (tow vehicle) 1 and a trailer (towed vehicle) 2, and the tractor (tow vehicle) 1 and the trailer. The (towed vehicle) 2 is configured to be connected by a coupler 3 so as to be rotatable around a connecting shaft extending in a substantially vertical direction. The coupler 3 can be configured so that the tractor (towed vehicle) 1 and the trailer (towed vehicle) 2 can be separated.

  The trailer (towed vehicle) 2 is connected to a tractor (towed vehicle) 1 so as to be rotatable about a connecting shaft extending in a substantially vertical direction, and the trailer (towed vehicle) 2 is connected to the tractor (towed vehicle) 1. The rotation angle around the shaft is referred to as a connection angle.

  In FIG. 1, reference numeral 4 denotes a steering angle sensor (steering sensor) for detecting the steering angle of the steering, and reference numeral 5 denotes information about sound such as sound and voice to the driver (driver). It is a speaker for transmitting through hearing.

Here, the driving operation at the time of turning of the connected vehicle 10 that is considered difficult to drive (such as entering a garage) will be described.
(1) When the connected vehicle 10 is moved backward in a certain target direction, such as when entering the garage in the reverse direction, first, the trailer 2 is turned (rotated) so that the rear end side of the trailer 2 faces the target direction. ) Therefore, as shown in FIG. 3 (A), in order to give the trailer 2 an opportunity to turn (rotate) the tractor 1, the handle is cut in the direction opposite to the target direction.

  (2) Next, when the rotation (retracting direction) of the trailer 2 can be oriented, as shown in FIG. 3 (B), the steering wheel operating amount (steering angle) of the tractor 1 is kept constant and the coupling angle θ is maintained. The connected vehicle 10 is moved backward while maintaining the above constant.

  (3) Then, as shown in FIG. 3C, when the trailer 2 side coincides with the target direction (for example, when it becomes parallel to the garage frame, etc.), the steering wheel is returned to the straight position until it reaches the fixed position. Retreat.

  Therefore, if the connection angle θ between the tractor 1 and the trailer 2 of the connected vehicle 10 can be acquired, the driver can be provided with information on the connection angle θ and the predicted traveling direction of the trailer 2 (see FIG. 6B). Yes, it can contribute to assisting driving in garage in reverse.

  Here, in addition to being extremely difficult to drive the connected vehicle 10 backward, it is an operation while confirming the safety of the surroundings, so the driver cannot afford to watch the monitor during the reverse drive, and the visual of the monitor etc. There was an actual situation that effective driving support was not possible by the presentation of information via

  In addition, as a result of various examinations, experiments, and the like, the present inventor is one of the information in which increase / decrease (change) of the connection angle with respect to the current steering angle is important in order to smoothly perform the reverse operation of the connection vehicle 10. As a result, it was found that providing such information can sufficiently contribute to assisting the driver to drive backwards. In other words, to teach the driver that the current steering angle δ is in a state where the coupled vehicle 10 can be moved backward while maintaining the coupling angle θ (the state of FIG. 3B), I thought it could be very useful information.

  For this reason, in the backward driving support system (apparatus) for a connected vehicle according to the present embodiment, as a method for providing information to the driver, it is related to the connection angle θ in addition to providing visual information or instead of providing visual information. Information is provided to the driver via the speaker 5 or the like as information related to voice, beep sound, sound effect, music and other sounds.

  As an example of the contents, for example, a region in which the connection angle θ increases more than a predetermined value due to the relationship between the steering angle δ and the connection angle θ that can be geometrically calculated in a low speed range (the vehicle speed when reversing is 3 km / m or less). (See area A in FIG. 4), the connection angle θ is maintained within a predetermined range (maintained substantially constant) (see area B and the constant curve in FIG. 4), and the connection angle θ decreases more than a predetermined value. A region (see region C in FIG. 4) is obtained, and the relationship shown in FIG. 4 is stored in advance in a ROM or the like in the ECU (electronic control unit).

  That is, in the present embodiment, for example, when the connection angle θ increases more than a predetermined value as a change in the connection angle θ when the vehicle is moved backward while maintaining the current steering angle δ (region A in FIG. 4). The connection angle θ falls within a predetermined range (see region B in FIG. 4), and the connection angle θ decreases to a predetermined value or more (see region C in FIG. 4).

  Then, the ECU determines whether the connection angle θ increases, decreases, or is constant (substantially constant) when reversing at the current steering angle δ (maintaining the current steering angle δ). Inform the driver by voice.

  For example, as shown in FIG. 4, when the connection angle θ increases, a beep sound (warning sound) (for example, beep, beep, beep,...) Is emitted from the speaker 5 or the like at relatively long intervals. When the connection angle θ decreases, a beep (warning sound) (for example, a beep, a beep, a beep, etc.) is emitted at a relatively short interval, and when the connection angle θ is substantially constant (does not change), there is no sound. By changing the way the sound is emitted according to the state, such as making a sound or continuing with a small sound, the driver is notified of the change degree (change degree) of the connection angle θ.

  Further, when the increase / decrease of the connection angle θ with respect to the current steering angle δ is relatively large (when the current steering angle δ is maintained, the degree of change is abruptly away from the current connection angle θ). By gradually increasing the volume according to the size of the vehicle, it is possible to notify the driver of the state and recognize it.

  When the connection angle θ increases due to the recorded voice or the like, the fact is notified. When the connection angle θ decreases, the fact is notified, and when the connection angle θ is substantially constant (does not change). May be configured to notify that effect.

  When the driver reverses at the current steering angle δ in this way, the connection angle θ of how the connection angle θ changes or whether the current connection angle θ is maintained constant as it is. Information related to changes can be obtained accurately and immediately through hearing as sound information without looking at a monitor, etc., so it is possible to immediately determine how to handle the steering wheel thereafter. .

  Therefore, the driver can easily and immediately grasp the traveling direction (reverse driving condition) on the trailer side without paying attention to a monitor or the like particularly in the scene as shown in FIG. The driver can perform a smooth reverse operation while visually checking surrounding safety.

  In other words, the information related to the change in the connection angle θ can be accurately and immediately transmitted to the driver through the auditory sense as a sound information when the connected vehicle is driven backwards. The driver's arm (as compared to the case where information is communicated to the driver visually such as a conventional monitor display) It is possible to contribute to the realization of smooth reverse operation without depending on skill.

  As described above, according to the present embodiment, while the configuration is relatively simple and low-cost, the connection angle is set during the backward operation of the connected vehicle including the tractor (towed vehicle) and the trailer (towed vehicle). By providing related information to the driver as information related to voice, beep sound, sound effect, music and other sounds, it is possible to effectively support the backward driving of the connected vehicle.

  In the present embodiment, a backward driving support system (apparatus) for a connected vehicle as shown in FIG. 6 (A) is employed. For example, in a connection angle acquisition device (corresponding to the connection angle acquisition means according to the present invention). The connection angle θ between the tractor 1 and the trailer 2 of the connected vehicle 10 can be obtained as follows.

Further, in the connection angle acquisition device in the backward driving support system (device) for the connected vehicle according to the present embodiment,
As known information, the distance L1 between the axles of the tractor 1 (the distance between the steering wheel shaft and the rear wheel shaft), the distance L2 between the connection point (connection shaft) of the trailer 2 and the rear wheel shaft, and the connection point of the tractor 1 Using the distance Lh between the (connection shaft) and the rear wheel shaft, the connection angle θ is obtained (calculated) by calculation based on a geometric model as shown in FIG.

  Here, the connection angle θ is a rotation angle around a connection point (vertical connection shaft) by a coupler 3 between a tractor (towed vehicle) 1 and a trailer (towed vehicle) 2 (or a tractor on a plan view). (An angle at which the longitudinal central axis of the towing vehicle 1 intersects the longitudinal central axis of the trailer 2).

In the connection angle detection device according to the present embodiment, the actual steering angle δ of the front wheel (steering wheel) of the tractor 1 is obtained from the actual steering angle (actual steering angle) (actual steering angle) acquired by the steering angle sensor (steering vessel) 4 of the steering. Obtained based on (steering angle). Specifically, the actual steering angle δ can be acquired by, for example, multiplying the steering angle acquired by the steering angle sensor 4 of the steering by the gear ratio of the steering gear box.
The steering angle sensor 4 is a sensor that is already mounted on the connected vehicle 10 for other purposes (DSC (Dynamic Stability Control) or the like).
The configuration for acquiring the actual steering angle in the present embodiment corresponds to the steering angle acquisition means according to the present invention.

In the present embodiment, the wheel speed V1 of the rear wheel of the tractor 1 is acquired by the wheel speed sensor, and the wheel speed V2 of the rear wheel of the trailer 2 is acquired by the wheel speed sensor. For example, it can be obtained by considering the tire diameter in the rotational speed. When there is a speed difference between the left and right wheels, the average value of the left and right wheels can be used as a representative value.
The wheel speed sensor for the rear wheel of the tractor 1 and the wheel speed sensor for the rear wheel of the trailer 2 are already installed for other purposes (DSC (Dynamic Stability Control), anti-lock brake system, etc.). It is a sensor.

In FIG.
θ: Connection angle (obtained by calculation)
δ: Actual steering angle (actual steering angle) (obtained based on the output of the steering angle sensor 4)
L1: Distance between tractor axles (wheelbase) (known value) (input or stored in computer)
L2: Distance from connecting point to trailer rear axle (known value) (input or stored in computer)
Lh: Coupler offset (distance from connecting point to rear wheel shaft of tractor) (known value) (input or stored in computer)
V1: Wheel speed of the rear wheel of the tractor (revolving speed of the rear wheel axis with respect to the turning center of the tractor) (obtained based on the output of the wheel speed sensor)
V2: Wheel speed of the rear wheel of the trailer (the turning speed of the rear wheel shaft with respect to the turning center of the trailer) (obtained based on the output of the wheel speed sensor)
Vc: Connection point speed (obtained by calculation)
R1: Distance from connecting point to tractor turning center (obtained by calculation)
R2: Distance from connecting point to trailer turning center (obtained by calculation)
R3: The shortest distance from the vehicle center line X of the tractor (the center line in the width direction of the rear wheel shaft) to the tractor turning center (obtained by calculation)
R4: The shortest distance from the vehicle center line Y of the trailer (the center line in the width direction of the rear wheel shaft) to the trailer turning center (obtained by calculation)
α: Angle (intersection angle) between the vehicle center line X of the tractor and the line connecting the connecting point and the tractor turning center (obtained by calculation)
It is defined as

According to the geometric model of FIG.
From the relationship of Vc / V1 = R1 / R3, V2 / Vc = R4 / R2,
V2 / V1 = R4 / R2 / R1 / R3 (Formula 1)

R4 / R2 = cos (π / 4 + θ−α) (Formula 2)

Also,
R3 = L1 / tan δ
R1 = (Lh ² + R3 ² ) ^1/2 = (Lh ² + (L1 / tan δ) ² ) ^1/2
R1 / R3 = ((Lh · tan δ) ² + L1 ² ) ^1/2 / L1 (Formula 3)

α = tan ⁻¹ (L1 / (Lh · tan δ)) (Formula 4)

Here, by substituting Equation 2, Equation 3, and Equation 4 into Equation 1,
cos (π / 4 + θ−α) = V 2 / V 1 · L 1 / ((Lh · tan δ) ² + L 1 ² ) ^1/2

θ = cos ⁻¹ (V2 / V1 · L1 / ((Lh · tan δ) ² + L1 ² ) ^1/2 −π / 4 + α
^{= Cos -1 (V2 / V1 ·} L1 / ((Lh · tanδ) 2 + L1 2) 1/2 -π / 4 +
tan ⁻¹ (L1 / (Lh · tan δ))
It becomes.
That is,
... (Formula A)
Thereby, the connection angle θ can be obtained (detected) by calculation.

  As described above, according to the connection angle acquisition (detection) device according to the present embodiment, the sensors already mounted on the vehicle are utilized, and the calculation based on the above-described geometric model enables simple and low cost. The connection angle θ between the tractor 1 and the trailer 2 of the connected vehicle 10 can be acquired (detected).

  In addition, according to the connection angle acquisition (detection) device for a connected vehicle according to the present embodiment, even when trailers 2 having different lengths (L2) are connected, it is simply necessary to change the value of L2. The connection angle θ between the tractor 1 and the trailer 2 of the connected vehicle 10 can be acquired (detected).

However, the connection angle acquisition unit according to the present invention is not limited to the above, and may be configured to acquire the connection angle θ using a connection angle sensor or the like.
As the connection angle sensor (connection angle detection device), for example, those described in Japanese Utility Model Laid-Open No. 2002-145133, Japanese Patent Application Laid-Open No. 11-160063, Japanese Patent Application Laid-Open No. 08-332973, and the like are used. You can also

  According to the connection angle acquisition (detection) device of the connected vehicle according to the present embodiment as described above, the acquisition (detection) of the connection angle of the connection vehicle including the tractor and the trailer can be performed with a relatively simple and low-cost configuration. Therefore, the connection angle can be acquired (detected) without requiring special hardware.

  By the way, in each said embodiment, a connection vehicle is not limited to a semi-trailer, but a full trailer (a tractor having a towing function and a mounting function is connected to tow a trailer having only a mounting function without a towing function. It can also be applied to a simple connected vehicle).

  Further, in the case where the rear wheel shafts of the trailer 2 are two shafts arranged in the front-rear direction (FIGS. 3 and 6A), the average value of the rear wheel front and rear two shafts is set to L2 or V2 in the geometric model of FIG. By using it as a value, it can be processed (handled) in the same manner as described above.

  Each embodiment described above is only an example for explaining the present invention, and various modifications can be made without departing from the gist of the present invention.

1 Tractor (towing vehicle)
2 Trailer (towed vehicle)
3 Coupler 4 Steering sensor (steering angle sensor)
5 Speaker 10 Connecting vehicle (semi-trailer)

Claims (2)

A reverse drive assisting device for a connected vehicle comprising a tow vehicle and a towed vehicle connected rotatably around a connecting shaft extending in a substantially vertical direction with respect to the tow vehicle,
Steering angle acquisition means for acquiring the steering angle of the tow vehicle;
A connection angle acquisition means for acquiring a connection angle that is a rotation angle of a towed vehicle around a connection axis of the towed vehicle;
With
The change in the connecting angle when the vehicle is moved backward while maintaining the current steering angle is converted into information related to sound, and the information related to the sound is notified to the driver, thereby assisting the backward driving of the connected vehicle. In things,
The change in the connection angle when the vehicle is moved backward while maintaining the current steering angle is such that when the connection angle increases more than a predetermined value, when the connection angle falls within a predetermined range, the connection angle decreases more than a predetermined value. The connected vehicle reverse driving support device is characterized in that the driver is informed of sound information corresponding to each case . A connection angle θ, which is a rotation angle around a connection axis of the towed vehicle with respect to the towed vehicle,
δ: Actual steering angle (actual steering angle)
L1: Distance between tractor axles L2: Distance from coupling point to trailer rear axle Lh: Coupler offset (distance from coupling point to rear axle of tractor)
V1: Wheel speed of the rear wheel of the tractor (turning speed of the rear wheel shaft with respect to the turning center of the tractor)
V2: Wheel speed of the rear wheel of the trailer (the turning speed of the rear wheel shaft with respect to the turning center of the trailer)

The backward driving support device for a connected vehicle according to claim 1, wherein