JPH0675625A - Unmanned travel vehicle - Google Patents

Abstract

PURPOSE:To select an optional route among plural travel routes and make the vehicle travel by itself by controlling the vehicle by calculating a deviation quantity on the basis of a signal from a left or right guidance line sensor corresponding to the travel direction of the vehicle body once a fixed point nearby a branch or confluence point of the guidance line is detected. CONSTITUTION:When the unmanned travel vehicle 1 approaches the branch or confluence point and the fixed point installed near it is detected by a fixed point sensor 30, a main controller 15 selects a branch/confluence mode as the control mode of a steering system and the quantity of deviation of the vehicle body 2 from the guidance line 12 is calculated by using the signal from the left or right guidance sensor 13L or 13R corresponding to the vehicle body travel direction at the branch or confluence point. Then steering systems 16 and 18 are controlled on the basis of the deviation quantity and the vehicle 1 is made to travel in a specific direction along the guidance line 12 at the branch or confluence point, so the vehicle 1 selects an optional route among plural travel routes and travels by itself along the route.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an unmanned vehicle which detects a guide line buried in the ground and travels along the guide line.

[0002]

2. Description of the Related Art Such an unmanned vehicle is self-propelled along a guide line and a predetermined single traveling route.

[0003]

However, there is a case where it is desired to select an arbitrary route from a plurality of traveling routes and allow an unmanned vehicle to travel along the route. Conventionally, such a request can be met. could not.

Therefore, it is conceivable to form a plurality of running routes by connecting a plurality of induction wires in parallel to form a plurality of loops. The value is different, and the value of the electric current flowing through the long and high resistance induction wire becomes small, which causes a situation in which the induction wire cannot be detected by the unmanned vehicle.

As a method for solving the above problem, 1
It is conceivable to form a plurality of loops with a guide line to form a plurality of traveling routes. In this case, the steering direction is determined according to the determination of the traveling direction of the vehicle at the junction and the junction of the traveling route. It is necessary to establish a system control method.

The present invention has been made in view of the above circumstances, and an object thereof is an unmanned vehicle capable of selecting an arbitrary route from a plurality of traveling routes and self-propelled along the route. To provide.

[0007]

In order to achieve the above object, the present invention provides at least a pair of left and right guide wire sensors for detecting a guide wire provided on a traveling road, a steering motor for driving a steering system, and the guide wire. The guide line is configured to include a control unit that receives a signal from the line sensor, calculates a deviation amount from the guide wire of the vehicle body, and outputs a control signal according to the calculated deviation amount to the steering motor. In an unmanned vehicle that is self-propelled along with, a fixed point sensor that detects a fixed point installed near the junction and the junction of the guide line is provided, and when the fixed point sensor detects the fixed point, it substantially corresponds to the vehicle traveling direction. In addition, a branching / merging mode for calculating a deviation amount from the guide wire of the vehicle body based on a signal from the left or right guide wire sensor is added to the control means. .

[0008]

According to the present invention, when an unmanned vehicle approaches a junction or a junction, and a fixed point installed near the junction is detected by a fixed point sensor, the branch / merge mode is selected as a steering system control mode. The deviation amount from the guide line of the vehicle body is calculated using the signal from the substantially left or right guide line sensor according to the vehicle traveling direction (right or left) at the junction or the junction. Then, the steering system is controlled based on the deviation amount, and the vehicle is allowed to proceed in a predetermined direction along the guide line at the branch point or the merging point. It is possible to select any route from among the traveling routes of and to drive along the route.

[0009]

An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a perspective view showing a basic structure of an unmanned traveling vehicle according to the present invention, and FIG. 2 is a view showing a loop structure of a guide wire forming a traveling route of the unmanned traveling vehicle according to the present invention.
Is a block diagram showing a configuration of a steering control system of an unmanned vehicle, and FIG. 4 is a flowchart showing a control procedure of the steering system.

First, the basic structure of the unmanned traveling vehicle 1 will be described with reference to FIG. 1. The unmanned traveling vehicle 1 has a pair of left and right front wheels 3, which are steering wheels, and driving wheels at the front and rear of the vehicle body 2. The pair of left and right rear wheels 4 respectively rotatably supports the rear wheels 4.

A steering shaft 5 is erected obliquely upward toward the rear at a substantially central portion of the front portion of the vehicle body 2 in the vehicle width direction. A steering wheel 6 is provided at an upper end of the steering shaft 5 and a steering wheel 6 is provided at a lower end thereof. A pair of left and right tie rods 7 for steering the rear wheels 3 are connected to each other. The steering motor 8 is provided near the steering shaft 5.
The pulley 9 connected to the output shaft end of the steering motor 8 is connected to the pulley 10 connected to the steering shaft 5 via a belt 11.

Further, three guide wire sensors 13L, 13C, 13R for detecting the guide wire 12 buried in the ground are juxtaposed at appropriate intervals in the vehicle width direction at the lower front portion of the vehicle body 2. There is. These guide wire sensors 13L, 13C, 1
3R is a sensor that detects a magnetic field generated by a current flowing through the guide wire sensor 12, the guide wire sensor 13C is installed in the center in the vehicle width direction, and the guide wire sensors 13L and 13R are installed on the left and right sides of the guide wire sensor 13C. Has been done. And
Each induction wire sensor 13L, 13C, 13R includes an amplifier 14
It is electrically connected to the main controller 15 which is a control means via. The steering motor 8 is electrically connected to the main controller 15 via a steering controller 16.

On the other hand, an engine 17, which is a drive source, is mounted in a substantially central portion of the vehicle body 2. A carburettor 18 and a throttle motor 19 are connected to an intake system of the engine 17, and an output of the engine 17 is provided. Pulley 20 at the shaft end
Are bound together.

A cell dynamo 21 and a differential device 22 are arranged in front of and behind the engine 17, respectively, and between the pulleys 23 and 24 connected to the respective input shafts and the pulley 20. Belts 25 and 26 are wound around each. The throttle motor 19 and the cell dynamo 21 are electrically connected to the main controller 15 as shown.

By the way, rear axles 27 extend from both sides of the differential gear 22, and the rear wheels 4 are connected to the outer ends of the respective rear axles 27. And one rear axle 2
An electromagnetic brake 28 is provided between the seven. An encoder 29 is provided below the differential device 22, and the encoder 29 and the electromagnetic brake 28 are electrically connected to the main controller 15, respectively. The electromagnetic brake 28 may be attached to the input shaft of the differential device 22.

Further, a fixed point sensor 30 for detecting a fixed point (not shown) installed in the vicinity of a junction A and a junction B (see FIG. 2) of the traveling route is attached to the lower center of the vehicle body 2. The fixed point sensor 30 is electrically connected to the main controller 15.

An operation panel 31 is provided behind the steering wheel 6, and the operation panel 31 is provided.
A traveling direction switch 33 (see FIG. 3) is arranged above. By operating the traveling direction switch 33, the occupant can select the direction in which the unmanned traveling vehicle 1 should travel at the branch point. The traveling direction switch 33 is electrically connected to the main controller 15.

FIG. 3 shows the configuration of the steering control system. In the main controller 15, a deviation amount calculator 34 for calculating the deviation amount x from the guide wire 12 of the vehicle body 2 and the guide wire sensor. A / D converter 35 for converting an analog signal input from 13L, 13C, 13R through amplifier 14 into a digital signal, and to steering motor 8 according to deviation amount x calculated by deviation amount calculation unit 34. In addition to the steering motor current command value calculation unit 36 for calculating the current command value of, the memory 37, the fixed point sensor 30, and the interface 3 of the traveling direction switch 33.
8, 39, a fixed point determination unit 40, and a traveling distance (time) calculation unit 41 are incorporated.

By the way, in this embodiment, there is one guide wire 12 as shown in FIG.
Two loops L1 and L2 are formed by 2. That is,
The induction wire 12 led out from the AC power supply 42 is provided with a part forming a short side of a rectangle, a b part forming a long side of a rectangle by being bent at a right angle from the a part, and a certain large R from the b part. And a portion c that is bent by changing its direction by about 90 ° and extends parallel to the portion a, and is bent by changing its direction by about 90 ° in the same manner as described above from the portion c and forms a part of the long side of the rectangle. A portion, an e portion which is bent at a substantially right angle from the d portion and extends toward the b portion, is folded back from the e portion by 180 ° and branched from the b portion, and is directed substantially parallel to the e portion toward the d portion. F portion extending, the f
A certain large R is provided from the portion, the direction is changed by approximately 90 °, the portion is bent to join the d portion, and the g portion is connected to the AC power source 42 and extends on the extension line of the d portion. There is.

Thus, in this embodiment, two routes along the loops L1 and L2 formed by the guide lines 12 are formed as the traveling routes of the unmanned traveling vehicle 1, and the guide lines 12 are shown in the figure. An alternating current is passed in the direction of the arrow. At this time, at the junction point A where the f portion of the guide wire 12 branches from the b portion and the junction point B where it joins the d portion,
Currents in the same direction flow through the b portion and the f portion, and the d portion and the f portion.

Further, in this embodiment, the e portion of the guide wire 12 does not fulfill the original function of leading the unmanned vehicle 1, and one guide wire 12 constitutes two loops L1 and L2. Is an extra line needed for
Each predetermined distance t from the confluence point B (in this embodiment, t =
30 cm) apart from each other and substantially perpendicular to the b and d portions. This utilizes the property that when the guide wire 12 is moved across the guide wire sensors 13L, 13C, 13R at a right angle, the guide wire sensors 13L, 13C, 13L are hard to detect the magnetic field of the guide wire 12. This is to prevent the e portion of the guide wire 12 from being erroneously detected as a traveling road. At the predetermined distance t in FIG. 2, the b portion and the f portion and the d portion and the g portion of the guide wire 12 overlap each other (however, they are electrically kept in a non-contact state). .

When the cell dynamo 21 is driven based on a command from the main controller 15 and the engine 17 is started, a part of the output of the engine 17 is transferred to the pulley 2
0, the belt 26 and the pulley 24, and input to the differential device 22 and further transmitted to the rear wheel 4 via the rear axle 27, and the rear wheel 4 is driven to drive the unmanned traveling vehicle 1.
While the unmanned traveling vehicle 1 is traveling, the encoder 2
The signal from 9 is input to the traveling distance (time) calculating unit 41 (see FIG. 3) of the main controller 15, and the traveling distance (time) calculating unit 41 calculates the unmanned traveling based on the integrated value of the number of rotations of the rear wheels 4. The distance traveled by the vehicle 1, time, etc. are calculated and the results are output to the deviation amount calculator 34. Further, the throttle motor 19 receives a command from the main controller 15 and adjusts the opening degree of a throttle valve (not shown) to set the rotation speed of the engine 17, that is, the traveling speed of the unmanned traveling vehicle 1 to a predetermined value.

Here, the unmanned vehicle 1 according to the present embodiment.
The control of the steering system will be described with reference to the flowchart shown in FIG.

The control modes of the steering system in this embodiment are the normal mode selected when traveling at a point other than the junction A and the junction B in the traveling route shown in FIG. 2, and the junction A and the junction. A branch / merge mode that is selected when passing the point B is prepared. Although not shown, fixed points for notifying the branching point A and the merging point B are installed, and the memory 37 of the main controller 15 has a type of fixed point and its meaning, and a traveling direction switch. Meaning of 33, coefficient for calculation of deviation x,
Timing for returning from the branching / merging mode to the normal mode (traveling distance or traveling time from the branching point A or the joining point B of the unmanned vehicle 1) and the like are input in advance.

Thus, while the unmanned traveling vehicle 1 is traveling, the presence or absence of a fixed point is detected by the fixed point sensor 30 provided in the vehicle 1 (STEP 1 in FIG. 4), and a point where the fixed point is not detected (that is, , A point other than the junction A and the junction B), the normal mode is selected as the control mode of the steering system when the unmanned vehicle 1 is traveling, and the deviation amount calculator 34 of the main controller 15 causes the A / D Signals V _L , V _C , V from the inductive sensors 13L, 13C, 13R digitized by the converter 35.
_The deviation amount x is calculated by the following equation using all of _R (STEP 2 in FIG. 3).

[0027]

[Number 1] _{x = f1 (V L, V} C, V R) ... (1) above (1) the deviation calculated amount x by formula is inputted to the steering motor current command value calculating unit 36, the arithmetic unit 3
In 6, the current command value to the steering motor 8 corresponding to the deviation amount x (the current command value corresponding to the deviation amount x = 0) is calculated (STEP 3 in FIG. 4), and the result is output to the steering controller 16. Is performed (STE in FIG. 4
P4). Then, the steering controller 16 controls the drive of the steering motor 8, whereby the steering shaft 5 shown in FIG. 2 is rotated in a predetermined direction by a predetermined angle, and the front wheels 3 are steered in the same direction by a predetermined amount. As a result, the unmanned traveling vehicle 1 is self-propelled along the guide line 12.

Next, for example, when the unmanned vehicle is traveling in the direction of the arrow shown in the figure along the portion b of the guide line 12 shown in FIG. 2, the fixed point sensor 30 is installed near the branch point A and the fixed point is not shown. Upon detection of, the detection signal is input to the fixed point determination unit 40 via the interface 38 of the main controller 15 shown in FIG. In the fixed point determination unit 40, the memory 37
Based on the type and meaning of the fixed point previously input to, the direction (right or left) in which the unmanned vehicle 1 should travel is determined based on the detected fixed point (STEP 5 in FIG. 4), and the result is calculated as the deviation amount calculation unit 34. To enter. Alternatively, when the occupant operates the traveling direction switch 33 on the operation panel 31 to select the traveling direction of the unmanned traveling vehicle 1, the signal of the traveling direction switch 33 is directly transmitted via the interface 39 to the deviation amount calculating unit 34. Entered in.

If the direction in which the unmanned vehicle 1 should travel at the branch point A is to the left, the left branch mode is selected as the control mode (STEPs 6 and 7 in FIG. 4), and the deviation amount calculation unit 34 displays the left side. And central guide wire sensor 13L, 13
The deviation amount x is calculated by the following equation using the signals V _L and V _C from _C (STEP 8 in FIG. 4).

[0030]

[Number 2] _{x = f2 (V L, V} C) ... (2) (2) (deviation of the vehicle body 2 from part b of the induction line 12) the calculated deviation by equation x is the steering motor current command The value is input to the value calculation unit 36, and the calculation unit 36 calculates a current command value to the steering motor 8 corresponding to the deviation amount x (STEP 9 in FIG. 4), and the result is output to the steering controller 16. (STEP 10 of FIG. 4). Then, the steering controller 1
Reference numeral 6 controls the drive of the steering motor 8, whereby the steering shaft 5 is rotated in a predetermined direction by a predetermined angle and the front wheels 3 are steered in the same direction by a predetermined amount, whereby the unmanned vehicle 1 is guided by a guide wire. You can go straight along the part 12b. In this case, the signal V
With V _R in addition to the _L, for the impossible normal steering control, ignoring the signal V _R in the present embodiment.
In some cases, both signals V _L and V _R may be used to multiply both by a predetermined coefficient, and substantially the deviation of the vehicle body may be calculated by the signal V _L.

On the other hand, when the traveling direction of the unmanned vehicle 1 is to the right, the right branch mode is selected as the control mode (STEPs 6 and 11 in FIG. 4), and signals from the center and right side inductive sensors 13C and 13R are selected. The deviation amount (deviation amount of the vehicle body 2 from the f portion of the guide wire 12) x is calculated using V _C and V _R by the following equation (STEP 12 in FIG. 4).

[0032]

Equation 3] _{x = f3 (V C, V} R) ... (3) (3) (deviation of the vehicle body 2 from f portion of the guide wire 12) the calculated deviation by formula x is similar to the above It is input to the steering motor current command value calculation unit 36, and the calculation unit 36 calculates a current command value for the steering motor 8 based on the deviation amount x (STEP 9 in FIG. 4), and the result is sent to the steering controller 16. Is output (STEP 10 in FIG. 4). Then, similarly to the above, the steering controller 16 controls the drive of the steering motor 8, whereby the steering shaft 5 is rotated in a predetermined direction by a predetermined angle, and the front wheel 3 is moved in the same direction (to the right) by a predetermined amount. The driverless vehicle 1 is steered, and thereby the unmanned traveling vehicle 1 travels along the f portion (branch portion) of the guide wire 12. In this case, if V _L is used in addition to the signal V _R , normal steering control becomes impossible, so the signal V _L is ignored in this embodiment. In some cases, both signals V _L and V _R may be used to multiply both by a predetermined coefficient, and substantially the deviation of the vehicle body may be calculated by the signal V _R.

By the way, after the control mode is switched from the normal mode to the branching / merging mode, the traveling distance or traveling time from the branch point A of the unmanned vehicle 1 traveling on the b portion or the f portion of the guide wire 12 is as described above. Is calculated by the mileage (time) calculator 41 of the main controller 15 (STEP 13 in FIG. 4), and if the value exceeds a predetermined value,
The control mode is returned from the branch / merge mode to the normal mode (STEPs 14 and 15 in FIG. 4), and thereafter, the signals V _L from all the induction wire sensors 13L, 13C and 13R,
The steering system is controlled using V _C and V _R (STEPs 1 to 4 in FIG. 4), and the unmanned traveling vehicle 1 travels along the b, c or f portion of the guide line 12. In this embodiment, the control mode is returned to the normal mode based on the traveling distance or time of the unmanned traveling vehicle 1. However, in order to inform that the control mode can be returned to the normal mode during the traveling route. It is also possible to provide a fixed point of and to return the control mode to the normal mode when this fixed point is detected.

When the fixed point sensor 30 installed in the unmanned traveling vehicle 1 detects a fixed point (not shown) installed in the vicinity of the confluence B, the direction in which the unmanned traveling vehicle 1 should travel is determined again (FIG. 4). STEP 1, 5). In this case, the direction in which the unmanned traveling vehicle 1 should travel is automatically determined depending on the type of fixed point, that is, whether the unmanned traveling vehicle 1 is traveling along the c portion or the f portion of the guide line 12.

That is, when the unmanned traveling vehicle 1 is traveling along the portion c of the guide line 12, it is determined that the direction to proceed at the junction B is left, and the left junction mode is selected (FIG. 4). 6), and the same control as described above (STEPs 8 to 10 in FIG. 4), the unmanned traveling vehicle 1 travels along the g portion of the guide line 12.

Further, when the unmanned traveling vehicle 1 is traveling along the f portion of the guide line 12, it is determined that the traveling direction at the junction B is right, and the right junction mode is selected (FIG. 4). 6) and the same control as described above (STEPs 12, 9, 10 in FIG. 4), the unmanned traveling vehicle 1 also travels along the g portion of the guide line 12.

When it is confirmed that the unmanned vehicle 1 has traveled from the junction B for a predetermined distance or time as described above (STEPs 13 and 14 in FIG. 4), the control mode is returned to the normal mode again. (STEP1 of FIG. 4
5), and thereafter all the guide wire sensors 13L, 13C, 13
The steering system is controlled using the signals V _L , V _C , and V _R from _R (STEPs 1 to 4 in FIG. 4), and the unmanned traveling vehicle 1 travels along the g portion of the guide line 12.

Thus, the unmanned traveling vehicle 1 has one guide line 1
2 along two loops L1, L2 formed by 2
It is possible to select an arbitrary route from the two traveling routes, but since the value of the current flowing through one guide wire 12 is constant, the unmanned traveling vehicle 1 is traveling along which route. However, it is possible to always reliably detect the guide wire 12 along the route and travel along the guide wire 12.

[0039]

As is apparent from the above description, according to the present invention, at least a pair of left and right guide wire sensors for detecting a guide wire provided on a traveling road, a steering motor for driving a steering system, and the guide The guide line is configured to include a control unit that receives a signal from the line sensor, calculates a deviation amount from the guide wire of the vehicle body, and outputs a control signal according to the calculated deviation amount to the steering motor. In an unmanned vehicle that is self-propelled along with, a fixed point sensor that detects a fixed point installed near the junction and the junction of the guide line is provided, and when the fixed point sensor detects the fixed point, the vehicle substantially moves according to the traveling direction of the vehicle body. In addition, since the branching / merging mode for calculating the deviation amount from the guide wire of the vehicle body based on the signal from the left or right guide wire sensor is added to the control means, the unmanned vehicle Effect that can be self-propelled along the route select any route from among a plurality of travel route is obtained.

[Brief description of drawings]

FIG. 1 is a perspective view showing a basic configuration of an unmanned traveling vehicle according to the present invention.

FIG. 2 is a diagram showing a loop configuration of guide lines forming a traveling route of an unmanned traveling vehicle according to the present invention.

FIG. 3 is a block diagram showing the configuration of a steering control system of an unmanned vehicle according to the present invention.

FIG. 4 is a flowchart showing a control procedure of a steering system.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Unmanned traveling vehicle 2 Vehicle body 8 Steering motor 12 Guide line 13L, 13C, 13R Guide line sensor 15 Main controller (control means) 30 Fixed point sensor A Branch point B Confluence point

Claims (1)

[Claims] 1. A pair of left and right guide wire sensors for detecting a guide wire provided on a traveling road, a steering motor for driving a steering system, and a guide wire of a vehicle body for receiving a signal from the guide wire sensor. In an unmanned vehicle that is configured to include a control unit that calculates a deviation amount and outputs a control signal corresponding to the calculated deviation amount to the steering motor, the self-propelled vehicle along the guide line, A fixed point sensor for detecting a fixed point installed near the branch point and the confluence point is provided, and when the fixed point sensor detects the fixed point, substantially based on the signal from the left or right guide line sensor according to the traveling direction of the vehicle body. An unmanned vehicle in which a branching / merging mode for calculating a deviation amount from a guide line of a vehicle body is added to the control means.