JP3632008B2 - Autonomous driving vehicle - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an autonomous driving track vehicle and an automatic driving method of the track vehicle.
[0002]
[Prior art]
Autonomous driving is desired for vehicles. In order to realize the automatic operation, line length control is indispensable. FIG. 14 shows a known automatic driving system. The vehicle body supported by the wheels 101 is provided with a position detector 102, an automatic operation unit 103, an output unit 104, and a driving / braking unit 105. As the position detector 102, a pulse generator that is axially coupled to the axle of the wheel 101 is preferably used. The calculation part of the automatic operation unit 103 is calculated based on the vehicle calculation travel distance which is a vehicle travel distance calculated based on the rotation speed of the wheel output from the position detector 102 and the rotation speed per unit time of the wheel. The vehicle calculation speed that is the vehicle speed and the vehicle calculation position that is the vehicle position calculated based on the vehicle calculation travel distance are obtained. The storage portion of the automatic driving unit 103 stores a target vehicle speed corresponding to the vehicle absolute position. The control part of the automatic operation unit 103 compares the target vehicle speed corresponding to the obtained vehicle calculation position with the vehicle calculation speed, and outputs an acceleration travel, constant speed travel, and braking output command corresponding to the excess or deficiency of both speeds. 106 is output. The output unit 104 executes acceleration travel, constant speed travel, and braking via the drive / brake unit 105 based on the output command 106.
[0003]
Such automatic driving control is effective only when there is no slip between the wheel 101 and the traveling path 107 or when the slip between them is so small that it can be ignored. In recent years, the increase in the transport capacity of vehicles has necessitated an increase in positive and negative acceleration. According to such an increasing tendency, the slip between the wheel and the travel path cannot be ignored. If a slip occurs to such an extent that the error between the vehicle calculation position and the absolute position where the vehicle actually exists cannot be ignored, automatic driving control cannot be executed.
[0004]
There is a need to establish technology that enables automatic operation regardless of whether or not there is a slip.
[0005]
[Problems to be solved by the invention]
An object of the present invention is to provide an automatic driving orbital vehicle and an automatic driving method for an orbital vehicle that can establish a technology that enables automatic operation regardless of whether or not there is a slip.
It is another object of the present invention to provide an automatic driving track vehicle capable of reducing the number of markers to reduce the railway laying cost, and an automatic driving method of the track vehicle.
[0006]
[Means for Solving the Problems]
Means for solving the problem is expressed as follows. Technical matters appearing in the expression are appended with numbers, symbols, etc. in parentheses. The numbers, symbols, and the like are technical matters constituting at least one embodiment or a plurality of embodiments of the present invention, or a plurality of embodiments, in particular, the embodiments or examples. This corresponds to the reference numbers, reference symbols, etc. attached to the technical matters expressed in the drawings corresponding to. Such reference numbers and reference symbols clarify the correspondence and bridging between the technical matters described in the claims and the technical matters of the embodiments or examples. Such correspondence or bridging does not mean that the technical matters described in the claims are interpreted as being limited to the technical matters of the embodiments or examples.
[0007]
An autonomous driving track vehicle according to the present invention is mounted on a vehicle body (5), wheels (3) that support the vehicle body (5) on the track (2), and the vehicle body (5), and is disposed on the track side. A detection unit (1) for detecting the absolute position of the plurality of markers (6) and a travel distance of the vehicle body (5) with respect to the absolute position detected by the detection unit (1) mounted on the vehicle body (5). And a control unit (14) for controlling the operation of the vehicle body (5) based on the difference between the absolute position and the calculated position. The calculation accuracy on the vehicle side and the absolute accuracy by detecting the position of the marker are in harmony, and it is practical within the range of calculation accuracy on the vehicle side, especially in the range of accuracy degradation due to slipping, without providing countless markers. Automatic operation with sufficiently high accuracy becomes possible.
[0008]
The plurality of absolute positions detected corresponding to the plurality of markers (6) become the operation control information that is exact for the operation control. Arbitrary positions in the section between each of the detected absolute positions are obtained by calculation. An arbitrary calculation position obtained by the calculation does not exactly match an arbitrary absolute position corresponding to the calculation position due to a physical factor such as slip. However, the absolute position cannot be known at the arbitrary calculation position. At any position that is not an absolute position that is detected, operation control can be performed based on the calculated position. The starting point of the calculation is an absolute position corresponding to an arbitrary marker among a plurality of markers that have passed in the past, and operation control is executed based on the difference between the absolute position and the calculation position. The absolute position of the marker that has passed recently is not always adopted as the starting point of the calculation. All absolute positions detected can be the starting point of the calculation. Since at least one of the detected absolute positions is employed as a calculation starting point, even if there is a detection error for one marker, the safety of operation control is reliably preserved.
[0009]
The calculation unit (7) calculates the calculation position based on the rotation speed of the wheel (3). Between the wheel (3) and the track (2), the calculation position does not always exactly match the absolute position due to physical causes such as slipping, but as described above, driving safety is ensured. Has been.
[0010]
It is important for the control unit (14) to reset the difference to zero if the above-described difference is within the set allowable range. This difference is calculated on the condition that a marker exists and the absolute position of the marker is detected. If there is a detection error, the difference is calculated based on the absolute position of the next marker and the calculation position corresponding to the absolute position. The absolute position of the marker serving as a reference for executing such a reset can be newly adopted as a calculation starting point.
[0011]
If the difference is not within the set allowable range, the control unit (14) outputs an abnormal signal. Here, the abnormal signal is a signal such as a vehicle stop signal, a warning to the driver, or a notification to the central control room, and is a signal outside the allowable difference range.
[0012]
It is preferable that a plurality of the arithmetic units (7) are mounted on the vehicle body (5) from the viewpoint that the degree of freedom of control can be further increased. The control unit (14) has a plurality of difference is calculated based on a plurality of operation positions required for each of a plurality of arithmetic units (7). If the minimum value of the absolute values of the plurality of differences is not within the allowable range, the above-described abnormal signal is output. Such anomaly determination is not based on the principle of majority voting, but originally based on a highly reliable detection / calculation technique.
[0013]
A plurality of rotation speeds are detected as the rotation speed of the wheel (3), and a plurality of differences are obtained based on the plurality of rotation speeds. The control unit (14) outputs an abnormal signal if the minimum value of the absolute values of the plurality of differences is not within the allowable range. Preferably, the plurality of rotation speeds correspond to a plurality of axles, respectively. The magnitude of slip is more realistic when there is less slip.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Corresponding to the figure, in the embodiment of the autonomous driving track vehicle according to the present invention, the absolute position detector is arranged together with the wheel rotational speed corresponding position detector. As shown in FIG. 1, the wheel rotational speed corresponding position detector 1 is a device that detects the rotational angle position of the wheel 3 that is in frictional contact with the traveling path 2, and a well-known pulse generator is preferably exemplified. The rotation shaft of the pulse generator is axially coupled to the axle of the wheel 3 coaxially or synchronously.
[0015]
An absolute position detector 4 is arranged at an appropriate part of the vehicle body 5 of the vehicle. On the side of the travel path 2, in particular, the markers 6 are arranged on the travel line at appropriate intervals on the travel road surface. The absolute position detector 4 is a known proximity sensor that can detect the position of the marker 6 with high accuracy and high speed in response to the marker 6 electrically, magnetically, or electromagnetically. The content of the detection is data such as the presence of the marker 6 and a unique number unique to the marker 6.
[0016]
The vehicle body 5 is provided with an automatic driving unit 7 and a monitoring unit 8. The rotational angle position signal 9 output from the wheel rotational speed corresponding position detector 1 and the absolute position signal 11 output from the absolute position detector 4 are input to the automatic operation unit 7 and the monitoring unit 8. The automatic driving unit 7 obtains the vehicle calculation travel distance D based on the rotation angle position signal 9. Further, based on the vehicle travel calculation distance D, a vehicle calculation position (coordinate) X is obtained by calculation. If the reference position coordinate is X0,
X = X0 + D
[0017]
Here, as the reference position coordinates, all of the plurality of markers that have been passed and whose existence and the absolute position are detected, any plurality of markers, and one absolute position of the plurality of markers are adopted. obtain.
[0018]
As with the automatic driving unit 7, the monitoring unit 8 uniquely obtains the vehicle calculation position X-1. The vehicle body 5 further includes a position checking unit 13 and an output unit 14. The position checking unit 13 is connected to the output unit 14. The automatic operation unit 7 is connected to the position checking unit 13 together with the monitoring unit 8. The automatic operation unit 7 outputs the vehicle calculation position to the position checking unit 13, and the monitoring unit 8 outputs the vehicle calculation position to the position checking unit 13. The position checking unit 13 compares the vehicle calculation position X and the vehicle calculation position X-1, and if the difference between the vehicle calculation position X and the vehicle calculation position X-1 is within the allowable range, the output unit 14 sets an error range. Transfer information. If the difference between the vehicle calculation position X and the vehicle calculation position X-1 is not within the allowable range, the position checking unit 13 transfers information outside the error range to the output unit 14. When the difference is within the error range, the output unit 14 outputs the operation control command 12 received from the automatic operation unit 7 to the drive / brake unit 22 as it is. If the difference is outside the error range, the output unit 14 outputs an abnormal signal such as an emergency stop command to the driving / braking unit 22.
[0019]
As shown in FIG. 2, the markers 6 are not only arranged at fixed intervals, but are densely arranged on the road surface at the starting point A or a position in the vicinity thereof and at the arrival points B, C or in the vicinity thereof. Alternatively, they are arranged at the start point of the constant speed travel section and the end point of the constant speed travel section. It is preferable that the plurality of markers 6 be arranged at shorter intervals in a speed control fine section where a fine stop accuracy is required such as near the start point and near the end point of the route. It is more preferable that the number of markers 6 and the interval between the markers 6 are defined by increasing / decreasing according to route conditions (example: route length) and driving conditions (example: slippage based on acceleration / deceleration magnitude).
[0020]
As shown in FIG. 2, a plurality of operation sections in which acceleration and constant speed are respectively defined are set programmably. Since the appropriate acceleration can be obtained by calculation, it is not always necessary to define the acceleration. In each operation setting section, the target vehicle speed V ′ (X ′) is defined in a programmable manner corresponding to the vehicle absolute position X ′. In the acceleration section 17, an acceleration command 12 for increasing the vehicle calculation speed V (X) to the target vehicle speed V ′ (X ′) is transmitted to the output unit 14. The acceleration command 12 is equivalent to a momentary speed command. The vehicle calculation speed V (X) is obtained as V ′ (X), which is an operation pattern, and does not coincide with V ′ (X ′). As a result of the acceleration, slip occurs between the wheel 3 and the travel path 2, and the actual vehicle speed changes so as to be further entangled with the target vehicle speed V ′ (X ′), as indicated by a broken line curve in FIG. 3. Slip is caused by acceleration and deceleration based on the output of a motor such as a torque converter attached to an electric motor or a diesel engine generator, and further caused by gravity action on a downhill or uphill, and the actual vehicle speed is calculated by a vehicle calculation speed V ( X) larger or smaller. The vehicle calculation speed V (X) is calculated from moment to moment, and the vehicle is accelerated and decelerated from moment to moment, so slipping also occurs in the constant speed travel section 18. In the braking section 19, as shown in FIG. 4, a phenomenon opposite to the phenomenon in the acceleration section occurs, and the actual vehicle speed may exceed the vehicle calculation speed V (X).
[0021]
The area of the hatched portion, which is the integral of (actual vehicle speed−vehicle calculation speed), is the vehicle calculation distance calculated based on the signal output from the wheel rotational speed corresponding position detector 1 and the actual driving in which the vehicle actually traveled. This corresponds to an error (integrated line length error) as a difference from the distance (= vehicle calculation travel distance−actual travel distance). Such an error is not clear until the absolute position point where the marker 6 exists is reached. When the absolute position detector 4 reaches the absolute position where the marker 6 exists, the vehicle calculation position X and the vehicle calculation position X-1 calculated independently by the automatic operation unit 7 and the monitoring unit 8 are respectively The vehicle absolute position X ′ is corrected. Even after the correction, the vehicle calculation position X and the vehicle calculation position X-1 are output to the position checking unit 13, and the determination result as to whether they are within the error range or outside the error range is transferred to the output unit 14.
[0022]
If the difference between the vehicle calculation position X calculated by the automatic operation unit 7 and the vehicle calculation position X-1 calculated by the monitoring unit 8 is not within the set allowable error range, an alarm signal is sent from the position checking unit 13. In particular, an emergency stop signal is output, and the vehicle 5 outputs a stop or abnormal signal. If the difference between the vehicle calculation position X calculated by the automatic operation unit 7 and the vehicle calculation position X-1 calculated by the monitoring unit 8 is within the set allowable error range, the vehicle calculation speed is used as the vehicle speed command. A driving force signal 21 corresponding to V (X) is output from the output unit 14 and input to the driving / braking unit 22, and the wheel 3 is controlled to a rotational speed corresponding to the vehicle calculation speed V (X).
[0023]
FIG. 5 shows another embodiment of the autonomous driving track vehicle according to the present invention. In the present embodiment, a plurality of monitoring devices 8 are provided, and the rotation angle position signal 9 and the absolute position signal 11 are input to the automatic operation unit 7 and the plurality of monitoring units 8, respectively. The vehicle calculation travel distance X is obtained by the automatic driving unit 7 and the two monitoring units 8. The automatic operation unit 7 calculates the vehicle calculation travel distance X and outputs it to the position verification unit 13, and the first monitoring unit 8 calculates the vehicle calculation travel distance X-1 and outputs it to the position verification unit 13. The first monitoring unit 8 outputs a vehicle calculation position X-2. The difference between the vehicle calculation travel distance X and the vehicle calculation travel distance X-1, the difference between the vehicle calculation travel distance X-1 and the vehicle calculation travel distance X-2, the vehicle calculation travel distance X-2 and the vehicle calculation travel distance. One of the vehicle calculation travel distances within the allowable error range of the smallest difference from X is adopted. If the smallest of the three differences is not within the tolerance range, all data is discarded. By such a principle, the reliability of vehicle control is further improved, the reliability of automatic driving is increased, and an emergency stop due to a calculation error is avoided.
[0024]
FIG. 6 shows still another embodiment of the autonomous driving track vehicle according to the present invention. In this embodiment, a plurality of wheel rotational speed corresponding position detectors 1 are provided. The rotational angle position signals 9 output from the two wheel rotational speed corresponding position detectors 1 are input to the automatic operation unit 7 and the monitoring unit 8, respectively. The two rotational angle position signals 9 are checked for whether the difference between the input signals of the automatic operation unit 7 and the monitoring unit 8 does not exceed a certain value, thereby improving the reliability.
[0025]
FIG. 7 shows still another embodiment of the autonomous driving track vehicle according to the present invention. This embodiment is the same as the embodiment of FIG. 6 in that a plurality of wheel rotation speed corresponding position detectors 1 are provided. In the present embodiment, one wheel rotational speed corresponding position detector 1 is arranged on each of the front wheel side and the rear wheel side. When the difference between the calculation travel position X and the absolute position coordinate X ′ becomes large due to a single slip on the front wheel side or the rear wheel side, the two rotation angle position signals 9 are transmitted between the automatic operation unit 7 and the monitoring unit 8. The reliability of the calculation travel position X can be improved by detecting the abnormality when the difference between the input signals becomes a certain value or more.
[0026]
FIG. 8 shows still another embodiment of the autonomous driving track vehicle according to the present invention. In the present embodiment, a route condition storage unit 31 is added to the above-described embodiment. The route condition storage unit 31 is connected to the automatic operation unit 7 and the monitoring unit 8 in both directions. The route condition storage unit 31 stores a route speed pattern (operation pattern) 32 shown in FIG. In the route speed pattern 32, the speed is defined in all route sections (example: total length 65km). Markers 6 are regularly arranged on the travel path 2 at intervals of 1 km. All vehicles share the route speed pattern 32 or store a unique route speed pattern 32 for each vehicle.
[0027]
The route condition storage unit 31 has information about the distance distance X ′ (horizontal axis) and the target speed V ′ (X ′) in a programmable manner. The velocity V (X ′) necessarily includes information on positive and negative acceleration. Accordingly, the distance distance X ′ results in a function having time as a variable, and the target speed V ′ is represented by V ′ (X ′ (t)).
[0028]
At the first start, the current position of the vehicle is manually input and set in the automatic operation unit 7 and the monitoring unit 8. The route condition, the operation condition, and the stop position are set in the automatic operation unit 7 and the monitoring unit 8 via a setting device attached to the automatic operation unit 7. The setting is automated when the station staff or the driver inserts the IC card into which the route condition, the driving condition, and the stop position are input into the card insertion slot of the automatic driving unit 7.
[0029]
As shown in FIG. 10, the train starts at point A, stops at point B, starts at point B, stops at point C, starts at point C, stops at point D, and stops at point D. The driving conditions starting at are already input to the automatic driving unit 7. It is not necessary to set their departure time.
[0030]
The route speed pattern 32 defines the speed of a plurality of constant speed sections, but the acceleration in the vicinity of the point where the constant speed is changed is not defined. As shown in FIG. 10, the automatic driving unit 7 calculates and obtains acceleration during the transition from one constant speed section to the next constant speed section according to the acceleration condition. The operation control pattern shown in FIG. 9 can be calculated and tabulated already at the first departure time, or calculated in real time.
[0031]
If negative acceleration occurs due to resistance, control for maintaining the target speed V (X) is executed from moment to moment. Correction control for zeroing the above-described integral line length error is executed at the locations where the markers arranged at intervals of 1 km are present. Since the number of markers is large, the integral line length error is frequently zeroed and the accumulated error is frequently eliminated to zero.
[0032]
After the emergency stop, if the time has been set after the defect has been resolved, the departure drive is started at the moment when the current time is shifted to the programmable time. If the time has not been set, the operation is performed according to FIG. The automatic operation is resumed only by the input of the start signal by the judgment of the driver or the driver of the central command control room.
[0033]
If the route condition shown in FIG. 9 is set, any vehicle on the route can start automatic driving at any time. The arbitrary vehicle includes a work vehicle, a route inspection vehicle, a signal waiting vehicle, an emergency stop vehicle, and a forced stop vehicle based on the occurrence of an accident.
[0034]
In the present embodiment, individual technical features that are peculiar to the embodiments of FIGS. 1, 5, 6, and 7 can be applied as they are.
[0035]
FIG. 11 shows a modification of the marker arrangement. The plurality of markers 6 shown in FIG. 11 has unique position information corresponding to the arrangement position, and the first type marker 6-1 whose unique position information is detected by the absolute position detector 4 corresponds to the arrangement position. It includes a second type of marker 6-2 that has no unique position information and whose presence is detected by the absolute position detector 4. The first type marker 6-1 is a key point in terms of control, such as a station, a front area in the upward direction (traveling direction) of a traveling road with a large gradient, or a point where appropriate braking is applied when approaching the station. Be placed. By reducing the number of first type markers 6-1 that are expensive, the route construction unit price can be reduced.
[0036]
FIG. 12 illustrates a correction control method by eliminating the accumulated error. The markers are arranged at 1 km intervals. The solid line indicates the target travel distance X or the actual travel distance, and the broken line indicates the calculated travel distance. At the starting point A, the actual travel distance and the calculated travel distance are the same. In principle, the actual travel distance does not match the calculated travel distance at any actual vehicle position. For every 1 km on which the marker is placed, the calculated travel distance is forcibly matched with the actual travel distance (the position where the marker is present).
[0037]
FIG. 13 shows in detail the change in the accumulated error between the actual travel distance and the calculated travel distance between the 0 km point and the 1 km point. The accumulated error ΔL at an arbitrary actual point position X changes from time to time (for each position) in an increasing or decreasing manner. Positive and negative slip occurs in the uphill and downhill areas. There is no standard that can eliminate the accumulated error ΔL at any position point between 0 km and 1 km. A marker is a reference that exists only at appropriate intervals. The value of the calculated travel distance is reset to the actual travel distance (the position where the marker is present) so that the accumulated error becomes zero at the point where the marker 6 exists. Since such a forced correction is performed at an appropriate interval such as every 1 km, no error is accumulated beyond the appropriate interval.
[0038]
The marker 6 functions with a power source and has position information corresponding to the installation location individually. Alternatively, the marker 6 can function without a power source. In this case, the vehicle has a power source for supplying power to the marker 6 wirelessly. The marker 6 preferably has individual position information corresponding to the installation location.
[0039]
According to the invention, no temporal control is necessary. The speed V of the vehicle is determined by a function of the position coordinates X ′ of the marker existing point and the subsequent calculation coordinates. Since X ′ is independent of the time t, the accumulated error of the line length is reliably eliminated at the marker existing position. The destination can be reached with an allowable line length error range. In a certain section immediately before the stop position, the vehicle can be stopped at the target stop point with sufficient accuracy by sufficiently increasing the linear density of the marker presence. The time length control can be executed independently of the line length control of the autonomous driving track vehicle according to the present invention. The time length error is eliminated by changing the calculation speed V (X) to the correction speed {V (X) + ΔV ′ (X ′)).
[0040]
【The invention's effect】
The automatic driving track vehicle and the automatic driving method of the track vehicle according to the present invention have a small number of markers for detecting the absolute position, and the cost of railway construction is reduced.
[0041]
More specifically, the calculation accuracy on the vehicle side and the absolute accuracy by detecting the position of the marker are harmonized, and the number of markers is innumerable. In this range, automatic operation with practically sufficiently high accuracy becomes possible.
[Brief description of the drawings]
FIG. 1 is a circuit block diagram showing an embodiment of an autonomous driving track vehicle according to the present invention.
FIG. 2 is a graph showing the relationship between marker placement and travel speed.
FIG. 3 is a graph showing a target speed and a calculation speed of a vehicle position.
FIG. 4 is a graph showing a target speed and a calculation speed of a vehicle position in a braking section.
FIG. 5 is a circuit block diagram showing another embodiment of the autonomous driving track vehicle according to the present invention.
FIG. 6 is a circuit block diagram showing still another embodiment of the autonomous driving track vehicle according to the present invention.
FIG. 7 is a circuit block diagram showing another embodiment of the autonomous driving track vehicle according to the present invention.
FIG. 8 is a circuit block diagram showing another embodiment of the autonomous driving track vehicle according to the present invention.
FIG. 9 is a graph showing a route speed pattern.
FIG. 10 is a graph showing another route speed pattern.
FIG. 11 is a graph showing yet another route speed pattern.
FIG. 12 is a graph illustrating a cumulative error elimination method.
FIG. 13 is a graph showing another method of eliminating accumulated errors.
FIG. 14 is a circuit block diagram showing a known self-driving orbital vehicle.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Speed detector 2 ... Track 3 ... Wheel 4 ... Marker presence detector 5 ... Car body 6 ... Marker 6-1 ... 2nd type marker 6-2 ... 1st type marker 7 ... Holding unit 8 ... Other calculation units 14 ... Driving unit

Claims (3)

The vehicle body,
Wheels for supporting the vehicle body in a track;
A detection unit that is mounted on the vehicle body and detects absolute positions of a plurality of markers arranged on the track side;
An arithmetic unit mounted on the vehicle main body and calculating a travel distance of the vehicle main body with respect to an absolute position detected by the detection unit;
Look including a control unit for controlling the operation of the vehicle body based on a difference between the operation position and the absolute position,
The calculation unit calculates the calculation position based on the rotation speed of the wheel,
As for the rotation speed of the wheel, a plurality of rotation speeds are detected, and a plurality of the differences are obtained based on the plurality of rotation speeds,
The control unit outputs an abnormal signal if the minimum value of the absolute values of the plurality of differences is not within the allowable range,
The plurality of rotation speeds respectively correspond to a plurality of axles . The automatic driving orbital vehicle according to claim 1 , wherein the control unit resets the difference to zero if the difference is within a set allowable range. 3. The autonomous driving track vehicle according to claim 2 , wherein the control unit outputs an abnormal signal if the difference is not within the set allowable range.

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