Method for laying track systems and magnetic components for tracked vehicles

Abstract

To provide a track system and a method for laying magnetic components suitable for tracked vehicles. [Solution] In a route system 1 in which a tracked vehicle 2 travels, a magnetic tape 51 is laid along a route 5. During travel by the tracked vehicle 2, which is equipped with a magnetic sensor array 4 for detecting the magnetic tape 51, the magnetic strength of the magnetic tape 51 is greater at specific locations where the distance between the magnetic sensor array 4 and the road surface 500 increases beyond the sensor mounting height, compared to other locations in the route 5.

Description

Technical Field

[0001] The present invention relates to a path for automatically driving an endless track vehicle (crawler vehicle) equipped with crawlers.

Background Art

[0002] Conventionally, as a system for automating logistics within facilities such as factories and warehouses, systems that utilize magnetic components such as magnetic tapes laid along a path and magnetic markers arranged along a path are known. As such a system, a vehicle equipped with a magnetic sensor has been proposed that automatically travels while detecting, for example, a magnetic tape (see, for example, Patent Document 1).

[0003] In recent years, there have been attempts to apply vehicles with automatic driving introduced in factories and warehouses to agricultural lands such as construction sites and orchards. For example, an endless track vehicle can also handle uneven ground such as construction sites and orchards. If automatic driving of vehicles can be realized on agricultural lands such as construction sites and orchards, the burden on workers engaged in on-site work can be reduced, and work efficiency can be improved.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, tracked vehicles have the following problems. Unlike vehicles that travel on level roads, tracked vehicles, which can travel on uneven or bumpy paths, have a unique characteristic: the front or rear of the vehicle may lift when overcoming bumps or bumps. If this lifting occurs, the distance between the magnetic components placed on the road surface and the magnetic sensors on the vehicle increases, which may impair the reliability of detection by the magnetic components.

[0006] This invention has been made in view of the aforementioned conventional problems, and aims to provide a track system and a method for laying magnetic components suitable for tracked vehicles. [Means for solving the problem]

[0007] One aspect of the present invention is a path system in which magnetic components that exert a magnetic field on their surroundings are laid in a path on which a tracked vehicle travels, wherein the tracked vehicle is equipped with one or more magnetic detection circuits for detecting the magnetic components. The track system for a tracked vehicle is characterized in that, in a specific location where, while the tracked vehicle is in motion, the distance between any of the one or more magnetic detection circuits and the road surface increases beyond the mounting height, which is the height of the magnetic detection circuit relative to a flat road surface, the magnetic intensity of the magnetic component is greater than at the location where the distance between the tracked vehicle is in motion is equal to the mounting height.

[0008] One aspect of the present invention is a method for laying magnetic components that exert a magnetic field on their surroundings in a path on which a tracked vehicle travels, wherein the tracked vehicle is equipped with one or more magnetic detection circuits for detecting the magnetic components. The method for laying magnetic components is characterized by identifying a specific location where, while the tracked vehicle is in motion, the distance between one or more of the magnetic detection circuits and the road surface increases beyond the mounting height, which is the height of the magnetic detection circuit relative to a flat road surface, and by making the magnetic strength of the magnetic component greater at the specific location than at the location where the distance between the magnetic component and the road surface is greater than at the mounting height while the tracked vehicle is in motion. [Effects of the Invention]

[0009] In the route according to the present invention, at specific locations where the distance between the magnetic detection circuit of the tracked vehicle and the road surface increases, the magnetic strength of the magnetic components is increased. Therefore, even if the distance between the magnetic detection circuit and the road surface increases when the tracked vehicle passes through a specific location, there is less risk of insufficient magnetic force acting on the magnetic detection circuit. The tracked vehicle according to the present invention can reliably detect magnetic components laid on the route. [Brief explanation of the drawing]

[0010] [Figure 1] An explanatory diagram of the route the vehicle travels in Example 1. [Figure 2] A perspective view of the vehicle (tracked vehicle) that carries the transport box in Example 1. [Figure 3] A diagram illustrating the vehicle in Example 1. [Figure 4] A block diagram showing the configuration of the vehicle driving control system in Example 1. [Figure 5] A block diagram showing the configuration of the magnetic sensor array in Example 1. [Figure 6] An explanatory diagram showing how a vehicle travels along a magnetic tape in Example 1. [Figure 7] A graph showing the approximate distribution of magnetic measurement values ​​from magnetic sensors A1 to A12 in Example 1. [Figure 8] An explanatory diagram showing how the vehicle crosses the ridge in Example 1. [Figure 9]This graph shows the temporal changes in the magnetic intensity (maximum value) measured by the front magnetic sensor array, the magnetic intensity (maximum value) measured by the central magnetic sensor array, and the magnetic intensity (maximum value) measured by the rear magnetic sensor array as the vehicle crosses a ridge in Example 1. [Figure 10] An explanatory diagram showing how a vehicle crosses a valley in Example 1. [Figure 11] This graph shows the temporal changes in the magnetic intensity (maximum value) measured by the front magnetic sensor array, the magnetic intensity (maximum value) measured by the central magnetic sensor array, and the magnetic intensity (maximum value) measured by the rear magnetic sensor array as the vehicle crosses a valley in Example 1. [Figure 12] An explanatory diagram showing how the vehicle drives onto a step in Example 1. [Figure 13] This graph shows the temporal changes in the magnetic intensity (maximum value) measured by the front magnetic sensor array, the magnetic intensity (maximum value) measured by the central magnetic sensor array, and the magnetic intensity (maximum value) measured by the rear magnetic sensor array when the vehicle drives over a step in Example 1. [Figure 14] An explanatory diagram showing how a vehicle descends a step in Example 1. [Figure 15] This graph shows the temporal changes in the magnetic intensity (maximum value) measured by the front magnetic sensor array, the magnetic intensity (maximum value) measured by the central magnetic sensor array, and the magnetic intensity (maximum value) measured by the rear magnetic sensor array as the vehicle descends a step in Example 1. [Figure 16] This graph shows the positional changes in the magnetic intensity (maximum value) measured by the front magnetic sensor array, the magnetic intensity (maximum value) measured by the central magnetic sensor array, and the magnetic intensity (maximum value) measured by the rear magnetic sensor array in the section spanning the front and rear of the ridge in Example 1. [Figure 17] An explanatory diagram of the method for laying magnetic tape in the section spanning the front and back of the ridge in Example 1. [Figure 18]Graph showing the positional changes of the magnetic intensity (maximum value) measured by the front magnetic sensor array, the positional changes of the magnetic intensity (maximum value) measured by the central magnetic sensor array, and the positional changes of the magnetic intensity (maximum value) measured by the rear magnetic sensor array in the section across the valley in Example 1. [Figure 19] Explanatory diagram of the magnetic tape laying method in the section across the valley in Example 1. [Figure 20] Graph showing the positional changes of the magnetic intensity (maximum value) measured by the front magnetic sensor array, the positional changes of the magnetic intensity (maximum value) measured by the central magnetic sensor array, and the positional changes of the magnetic intensity (maximum value) measured by the rear magnetic sensor array in the section across the ascending step in Example 1. [Figure 21] Explanatory diagram of the magnetic tape laying method in the section across the ascending step in Example 1. [Figure 22] Graph showing the positional changes of the magnetic intensity (maximum value) measured by the front magnetic sensor array, the positional changes of the magnetic intensity (maximum value) measured by the central magnetic sensor array, and the positional changes of the magnetic intensity (maximum value) measured by the rear magnetic sensor array in the section across the descending step in Example 1. [Figure 23] Explanatory diagram of the magnetic tape laying method in the section across the descending step in Example 1. [Figure 24] Explanatory diagram showing how the vehicle travels with one side on the embankment in Example 1. [Figure 25] Explanatory diagram showing how the vehicle travels while straddling a groove in Example 1.

Mode for Carrying Out the Invention

[0011] The embodiments of the present invention will be specifically described using the following examples. (Example 1) This example describes a path system 1 in which a magnetic tape 51, an example of a magnetic component that exerts magnetism on its surroundings, is laid along a path 5, and a method for laying the magnetic tape 51 along the path 5. This will be explained using Figures 1 to 25.

[0012] This example shows how to set up Route 5 (Figure 1) in an environment with uneven terrain and steps, such as a construction site or orchard. Route 5 is difficult to travel on with a four-wheeled vehicle. Therefore, in this example, a crawler-type vehicle 2 (hereinafter referred to as Vehicle 2) equipped with crawlers (caterpillars) is used to travel on Route 5.

[0013] Vehicle 2 automatically travels along the route 5 while detecting the magnetic tape 51 laid along the route 5. The magnetic tape 51 is an example of a magnetic component in which one side of the front and back surfaces is the north pole and the other side is the south pole. In this example, the magnetic tape 51 is laid so that the top surface (front side) is the north pole and the bottom surface (back side) is the south pole.

[0014] Vehicle 2 (Figures 1-3) is equipped with annular rubber belts, called crawlers 21L and 21R, on both sides of the vehicle body 2B. Vehicle 2 measures 1 m in length and 1.2 m in width. The vehicle body 2B measures 0.8 m in length and 0.7 m in width. The top surface of the vehicle body 2B forms a loading platform on which a transport box 200 or the like can be placed. A rod-shaped magnetic sensor array 4 is mounted on the vehicle body 2B so as to be aligned with the vehicle width direction (lateral direction).

[0015] The vehicle 2's driving control system is electrically configured around a control circuit 20 (Figures 3 and 4). The control circuit 20 is electrically connected to a left motor 24L that rotates the left crawler 21L, a right motor 24R that rotates the right crawler 21R, a speed sensor 26L that measures the driving speed of the left crawler 21L, a speed sensor 26R that measures the driving speed of the right crawler 21R, a magnetic sensor array 4, and other components. Note that in Figure 3, the motors 24 and speed sensors 26 are not shown.

[0016] Vehicle 2 can change the orientation of its body 2B (vehicle orientation, yaw angle) according to the difference in the driving speed of the left and right crawlers 21L and R. By setting a difference in driving speed while driving the left and right crawlers 21L and R in the same direction, vehicle 2 can be made to travel along an arc-shaped trajectory. By driving the left and right crawlers 21L and R in opposite directions, a spin turn is also possible, which changes the orientation of the body 2B without changing its position.

[0017] The control circuit 20 (Figure 4) is composed of a CPU that performs various calculations, memory elements such as ROM and RAM, etc. The control circuit 20 is equipped with an I / O circuit that performs communication with external circuits. The control circuit 20 performs communication with external circuits such as the magnetic sensor array 4, motor 24, and speed sensor 26 via the I / O circuit.

[0018] The control circuit 20 acquires the detection results of the magnetic tape 51 by the magnetic sensor array 4. The detection results of the magnetic tape 51 include the lateral deviation of the vehicle 2 relative to the magnetic tape 51. The control circuit 20 controls the movement of the vehicle 2 so that the lateral deviation of the vehicle 2 relative to the magnetic sensor array 4 approaches zero, for example. Through this control by the control circuit 20, automatic movement of the vehicle 2 along the magnetic tape 51 is realized.

[0019] The magnetic sensor array 4 (Figure 5) is an example of a magnetic measurement circuit mounted on the underside of the vehicle 2 to acquire magnetic measurement values ​​representing the strength of the magnetic field acting from the magnetic tape 51. The mounting height of the magnetic sensor array 4, relative to a flat road surface, is approximately 8 cm. The mounting height of the magnetic sensor array 4 (referred to as the sensor mounting height) is the distance between the magnetic sensor array 4F and the road surface 500 when the vehicle 2 is located on a flat surface. In this example, the sensor mounting height of the magnetic sensor array 4 is constant regardless of whether it is mounted at the front, middle, or rear of the vehicle 2.

[0020] The magnetic sensor array 4 includes a signal acquisition unit 41 that acquires magnetic measurement values ​​(magnetic intensity) from 12 magnetic sensors An (where n is an integer from 1 to 12), a detection processing unit 43 that incorporates a CPU (not shown), and an output unit 45 that outputs the detection processing results.

[0021] The magnetic sensor array 4 is rod-shaped, with 12 magnetic sensors An arranged along its longitudinal direction at 5 cm intervals. In this example, the magnetic sensors An are MI sensors that detect magnetism using the known MI effect (Magneto Impedance Effect). The direction of magnetic force measured by each magnetic sensor An is the same. The magnetic sensor array 4 is mounted on the vehicle 2 so that the strength of the magnetic field acting in the vertical direction can be measured.

[0022] The detection processing unit 43 (Figure 5) of the magnetic sensor array 4 is an arithmetic circuit that performs detection processing to detect the magnetic tape 51. The detection processing unit 43 is composed of a CPU that performs various calculations, memory elements such as ROM and RAM, etc., although it is not shown in the figure. The detection processing unit 43 acquires 12 magnetic measurement values ​​from the magnetic sensor An at a frequency of 3 kHz and performs detection processing.

[0023] The crawler-type (continuous track) vehicle 2 has a running characteristic in which the gap between the vehicle body 2B and the road surface does not fluctuate much. Therefore, when running on a flat road surface, the distance between the road surface and the magnetic sensor array 4 does not deviate significantly from the sensor mounting height, which is the design specification value for the mounting height of the magnetic sensor array 43. In a normal running state in which no lift-up occurs, the maximum value of the magnetic measurement value measured by the magnetic sensor array 4 (hereinafter referred to as the magnetic intensity measured by the magnetic sensor array 4) is almost constant.

[0024] For example, when the vehicle 2 is automatically driven using the magnetic tape 51 as shown in Figure 6, the 12 magnetic measurements (magnetic intensity acting in the vertical direction) from the magnetic sensor An form a magnetic intensity distribution in the vehicle width direction, as illustrated by the approximate curve in Figure 7. As described above, since the front surface of the magnetic tape 51 is the north pole, a peak in magnetic intensity appears at a position directly above the magnetic tape 51.

[0025] The detection processing unit 43 (Figure 5) detects the magnetic tape 51 by detecting the peak in the distribution of magnetic intensity in the vehicle width direction, as illustrated in Figure 7. The detection processing unit 43 identifies the position of this peak in the vehicle width direction as the position directly above the magnetic tape 51. The detection processing unit 43 then identifies the lateral deviation of the vehicle 2 relative to the magnetic tape 51. The detection processing unit 43 outputs the detection processing result to an external source via the output unit 45.

[0026] The detection processing results of the detection processing unit 43 include a statement that the magnetic tape 51 was detected, the lateral deviation of the vehicle 2 relative to the magnetic tape 51, and the maximum value of the magnetic intensity. The maximum value of the magnetic intensity is the peak of the approximation curve in Figure 7, which represents the distribution of magnetic intensity in the vehicle width direction. The detection processing results are input to the control circuit 20 and used for driving control as described above.

[0027] As described above, Route 5 in this example includes steps and undulations that are not easily traversed by a four-wheeled vehicle. When the tracked vehicle 2 travels, for example, when it goes over a step or crosses a ridge, a lift-up state occurs where either the front or rear side of the vehicle 2 lifts off the road surface. Also, for example when crossing a valley, a lift-up state may occur where the middle part of the vehicle 2 lifts off the road surface.

[0028] The behavior of such crawler-type vehicles is unique and differs from that of four-wheeled vehicles. In vehicle 2, if the magnetic sensor array 4 is mounted on a part that is lifted off the road surface, the magnetic strength acting from the magnetic tape 51 on the magnetic sensor array 4 may be insufficient, potentially impairing the reliability of detection of the magnetic tape 51.

[0029] The following describes the behavior of vehicle 2 (Figures 8, 10, 12, and 14) and the temporal change in the maximum magnetic intensity measured by the magnetic sensor array 4 (Figures 9, 11, 13, and 15) for the following cases: (1) crossing a ridge, (2) crossing a valley, (3) going up a step, and (4) going down a step. Note that the magnetic tape 51 (see Figure 6) is not shown in Figures 8, 10, 12, and 14, but these figures show vehicle 2 traveling along the magnetic tape 51.

[0030] The mounting locations of the magnetic sensor array 4 on vehicle 2 vary depending on the vehicle type and control method. Therefore, in this example, the magnetic sensor array 4F mounted on the front of vehicle 2, the magnetic sensor array 4C mounted on the central part of vehicle 2, and the magnetic sensor array 4R mounted on the rear of vehicle 2 are exemplified as the magnetic sensor array 4.

[0031] (1) When crossing a ridge For example, when vehicle 2 travels over a ridge 501, which is a convex undulation as shown in Figure 8, a lift-up state occurs at the front of the vehicle, followed by a lift-up state at the rear of the vehicle as the front lift-up state is resolved. Figure 8 shows the position and attitude of vehicle 2 between times t11 and t14. Note that times t12 and t13 are approximately the same time, before and after the resolution of the front lift-up state.

[0032] Vehicle 2 approaches ridge 501 at time t11, and thereafter, until time t12, the front of vehicle 2 is lifted away from the road surface 500. At time t13, this front lift is resolved, and in response, the rear of vehicle 2 also lifts away from the road surface 500. The transition from the front lift to the rear lift can occur as the front-to-rear weight balance of vehicle 2 changes as the vehicle moves forward.

[0033] After the transition to the rear-side lifted state, when vehicle 2 moves forward and passes the ridge 501, the rear of vehicle 2 lands on the road surface 500 and the rear-side lifted state is resolved (time t14). During the rear-side lifted state from time t13 to time t14, the tilt of vehicle 2 is approximately equal to the slope of the road surface 500 in front. Therefore, the rear-side lifted state is resolved as vehicle 2 moves forward.

[0034] When vehicle 2 crosses ridge 501 (Figure 8), the maximum value of the magnetic intensity measured by the magnetic sensor array 4F·C·R changes as shown in Figure 9, for example. The maximum value of the magnetic intensity is the peak in the magnetic intensity distribution in the vehicle width direction (see Figure 7, for example), and is detected by the detection processing unit 43. In the following description, the maximum value of the magnetic intensity measured by the magnetic sensor array 4 is referred to as the magnetic intensity measured by the magnetic sensor array 4.

[0035] As shown in Figures 8 and 9, until time t11, when the crawler 21L and R are not lifting and the vehicle 2 is in a normal driving state, the three magnetic intensities measured by the magnetic sensor array 4F, C, and R are all large and approximately equal in value. In the following explanation, the large magnetic intensity measured by the magnetic sensor array 4 when the distance between the magnetic sensor array 4 and the road surface 500 is the sensor mounting height specified in the design specifications is referred to as the reference intensity R.

[0036] The magnetic intensity measured by the front magnetic sensor array 4F gradually decreases from time t11 when the front of the vehicle begins to lift, and reaches its minimum at time t12, just before this lifting condition is resolved. When the front of the vehicle is resolved (time t13), the magnetic intensity measured by the front magnetic sensor array 4F returns to the reference intensity R. Thereafter, until the entire vehicle 2 passes the ridge 501 (time t14), the front of the vehicle 2 remains in contact with the road surface 500, and the front magnetic sensor array 4F remains in close proximity to the road surface 500. Therefore, until time t14, the magnetic intensity measured by the front magnetic sensor array 4F is maintained at the reference intensity R.

[0037] As shown in Figures 8 and 9, the magnetic intensity measured by the rear magnetic sensor array 4R is maintained at the reference intensity R from time t11, when the front lift-up state occurs, until time t12, when this lift-up state is maintained. At time t13, when the front lift-up state is resolved, the rear of the vehicle 2 transitions to a lift-up state where it is separated from the road surface 500, and the magnetic intensity measured by the rear magnetic sensor array 4R rapidly decreases to its minimum.

[0038] Subsequently, as vehicle 2 moves forward while its rear end remains lifted, the distance between the rear magnetic sensor array 4R and the road surface 500 gradually decreases, and the magnetic intensity measured by the magnetic sensor array 4R gradually increases. At time t14, when the entire vehicle 2 passes over the ridge 501, the magnetic intensity measured by the rear magnetic sensor array 4R returns to the standard intensity R as the rear end is released. After time t14, vehicle 2 returns to a normal driving state, and the magnetic intensity measured by the rear magnetic sensor array 4R is maintained at the standard intensity R.

[0039] The central part of vehicle 2 remains aligned with the road surface 500 until time t12, when the front end continues to be lifted. Therefore, the magnetic intensity measured by the central magnetic sensor array 4C is maintained at the reference intensity R until time t12. The transition from the front end to the rear end lifted, in response to the change in the front-to-rear weight balance of vehicle 2, occurs due to the forward rotation of vehicle 2 with the ridge 501 as the pivot point. During this transition, since the central part of vehicle 2 is located on the ridge 501, the central magnetic sensor array 4C is kept in close proximity to the road surface 500 (ridge 501) between times t12 and t13. Therefore, the magnetic intensity measured by the central magnetic sensor array 4C is maintained at the reference intensity R between times t12 and t13.

[0040] From time t13 onward, even if the rear magnetic sensor array 4R becomes levitated, the central magnetic sensor array 4C remains close to the road surface 500. From time t13 onward, the magnetic intensity measured by the central magnetic sensor array 4C is maintained at the reference intensity R. Thus, when vehicle 2 crosses the ridge 501, the magnetic intensity measured by the central magnetic sensor array 4C is generally maintained at the reference intensity R.

[0041] Furthermore, depending on the front-to-rear weight balance of vehicle 2, the center of rotation of vehicle 2's forward rotation, which transitions from a front-to-rear lift-up state to a rear-to-rear lift-up state, may not be located in the center of vehicle 2. In such cases, the magnetic intensity measured by the central magnetic sensor array 4C will decrease immediately before or after the forward rotation. The degree to which the magnetic intensity measured by the central magnetic sensor array 4C decreases, and the duration of this decrease, are both smaller than those for the front magnetic sensor array 4F and the rear magnetic sensor array 4R, which are further from the center of vehicle 2.

[0042] (2) When crossing a valley For example, when vehicle 2 travels across a concave valley 502 as shown in Figure 10, normal driving conditions are maintained until time t15 when vehicle 2 reaches the valley 502. At time t16, the front of vehicle 2 comes into contact with the front slope of the two opposing slopes on either side of the valley, and the rear of vehicle 2 comes into contact with the other slope.

[0043] At this time, the middle section of vehicle 2 becomes lifted off the road surface 500, and the central magnetic sensor array 4C separates from the road surface 500. Meanwhile, the front magnetic sensor array 4F and the rear magnetic sensor array 4R are both maintained in close proximity to the road surface 500. Subsequently, when vehicle 2 moves forward, at time t17, the entire vehicle 2 passes through the valley 502 and returns to a normal driving state.

[0044] As shown in Figures 10 and 11, when vehicle 2 travels across valley 502, both the front magnetic sensor array 4F and the rear magnetic sensor array 4R remain close to the road surface 500, so the detected magnetic intensity remains at the standard intensity R. On the other hand, the central magnetic sensor array 4C moves away from the road surface 500 while vehicle 2 is crossing the valley. Therefore, the magnetic intensity measured by the central magnetic sensor array 4C decreases as vehicle 2 crosses valley 502, and reaches its minimum when the central part of vehicle 2 reaches the deepest part of valley 502.

[0045] (3) When going over a step For example, when vehicle 2 drives onto a step 505 as shown in Figure 12, at time t21, after vehicle 2 reaches the step 505, the front of vehicle 2 drives onto the step 505, causing the front to rise and the vehicle 2 to tilt, and then a state of the front lift occurs. When the center of vehicle 2 passes over the step 505 (time t22), the front-to-rear balance of vehicle 2 changes as it moves forward, the front of the vehicle 2 lands on the road surface 500, and the state of the front lift is resolved (time t23).

[0046] When vehicle 2, having climbed onto step 505, is now on the higher step (time t23), the rear of vehicle 2 will be lifted up until the entire vehicle has passed step 505 (time t24). After time t24, when the entire vehicle 2 has passed step 505, it will return to its normal running state.

[0047] As shown in Figure 12, when vehicle 2 drives onto the step 505, the magnetic intensity measured by the magnetic sensor array 4F·C·R changes as shown in Figure 13. Until time t21, when vehicle 2 is in a normal driving state, the magnetic intensity measured by the magnetic sensor array 4F·C·R is always the reference intensity R.

[0048] When the front of the vehicle lifts up (time t21), the tilt of the vehicle 2 gradually increases as the vehicle 2 moves forward, and the distance between the front magnetic sensor array 4F and the road surface 500 gradually increases. As a result, the magnetic intensity measured by the front magnetic sensor array 4F gradually decreases, reaching a minimum just before the front lift-up condition is resolved (time t22). When the front lift-up condition is resolved (time t23), the magnetic intensity measured by the front magnetic sensor array 4F returns to the reference intensity R. Thereafter, until the entire vehicle 2 passes over the step 505 (time t24), the front of the vehicle 2 remains in contact with the road surface 500, and the magnetic intensity measured by the front magnetic sensor array 4F is maintained at the reference intensity R.

[0049] As shown in Figures 12 and 13, the magnetic intensity measured by the rear magnetic sensor array 4R is maintained at the reference intensity R from time t21, when the front lift-up state occurs, until time t22, when this lift-up state is maintained. At time t23, when the front lift-up state is resolved, the rear of the vehicle 2 transitions to a lift-up state where it is separated from the road surface 500, and the magnetic intensity measured by the rear magnetic sensor array 4R rapidly decreases to its minimum.

[0050] When the rear of the vehicle is lifted up while driving over the step 505, the vehicle 2 is on the higher step, while the rear of the vehicle 2 faces the road surface 500 of the lower step. This is a rear-side lift state in which the gap between the rear magnetic sensor array 4R and the road surface 500 is maintained at a constant level. This rear-side lift state continues until time t24 when the entire vehicle 2 passes over the step 505. Therefore, after the rear-side lift state occurs at time t23, the magnetic intensity measured by the rear magnetic sensor array 4R is maintained at a nearly constant minimum value until the entire vehicle 2 passes over the step 505 and the rear-side lift state is resolved (time t24). Then, when the rear-side lift state is resolved (time t24), the magnetic intensity measured by the rear magnetic sensor array 4R increases rapidly and returns to the reference intensity R.

[0051] The central magnetic sensor array 4C separates from the road surface 500 at the moment vehicle 2 drives onto the step 505 at time t21. Then, until just before time t22, when the central part of vehicle 2 reaches the step 505 and the transition occurs from a front-side lifted state to a rear-side lifted state, the degree of front-side lift of vehicle 2 increases, and the gap between the central magnetic sensor array 4C and the road surface 500 gradually widens.

[0052] At time t22, when the vehicle 2 turns forward and transitions from a front-side lifted state to a rear-side lifted state, the central part of the vehicle 2 rides onto the step 505, causing the central magnetic sensor array 4C to come close to the road surface 500 of the upper step, and the magnetic intensity measured by the central magnetic sensor array 4C returns to the reference intensity R. Then, from time t23 onward, after the transition to the rear-side lifted state, the central part of the vehicle 2 becomes aligned with the road surface 500 of the upper step, and the magnetic intensity measured by the central magnetic sensor array 4C is maintained at the reference intensity R.

[0053] (4) When going down a step For example, when vehicle 2 descends a step 506 as shown in Figure 14, after vehicle 2 reaches step 506 (time t25), the front of vehicle 2 faces the road surface 500 of the lower step with a gap between them, causing the front to lift up. When the center of vehicle 2 passes step 506 (time t26), the change in front-to-rear weight balance causes vehicle 2 to tilt downwards, and the front of vehicle 2 lands on the road surface 500, eliminating the lifted state at the front (time t27).

[0054] When the front of vehicle 2 makes contact with the lower step's road surface 500, vehicle 2 tilts downwards at the front and its rear lifts up. As vehicle 2 moves forward, the downward tilt at the front of vehicle 2 lessens, but the rear remains lifted up until the entire vehicle 2 passes over the step 506 (time t28). When vehicle 2 is tilted downwards at the front, the central part of vehicle 2 is lifted off the road surface 500 of the lower step. After the entire vehicle 2 passes over the step, the rear of vehicle 2 lands on the lower step's road surface 500, and the rear lift is eliminated.

[0055] As shown in Figure 14, when vehicle 2 descends the step 506, the magnetic intensity measured by the magnetic sensor arrays 4F·C·R changes, for example, as shown in Figure 15. Until time t25, when vehicle 2 is in a normal driving state, the magnetic intensity measured by the front magnetic sensor array 4F and the rear magnetic sensor array 4R are both at the reference intensity R.

[0056] The magnetic intensity measured by the front magnetic sensor array 4F decreases sharply to its minimum at time t25 when the front of the vehicle becomes lifted, and is maintained at this minimum value until just before this lifted state is resolved (time t26). At time t27, when the front of the vehicle becomes lifted, the magnetic intensity measured by the front magnetic sensor array 4F rapidly returns to the standard intensity R. After that, since the front of the vehicle 2 remains in contact with the road surface 500, the magnetic intensity measured by the front magnetic sensor array 4F is maintained at the standard intensity R.

[0057] As shown in Figures 14 and 15, the magnetic intensity measured by the rear magnetic sensor array 4R is maintained at the reference intensity R from time t25, when the front lift-up state occurs, until time t26, when this lift-up state is maintained. Subsequently, when the front lift-up state is resolved (time t27), the rear of the vehicle 2 transitions to a lift-up state where it separates from the road surface 500, and the magnetic intensity measured by the rear magnetic sensor array 4R rapidly decreases to its minimum value.

[0058] The lift at the rear of the vehicle 2 when descending the step 506 is caused by the downward tilt of the front of the vehicle 2. This lift at the rear continues until the entire vehicle 2 passes over the step 506 and the entire vehicle 2 makes contact with the lower step (time t28). As the vehicle 2 transitions from a lift at the front to a lift at the rear, the magnetic intensity measured by the rear magnetic sensor array 4R decreases sharply to a minimum, and then the downward tilt of the front of the vehicle 2 gradually eases as the vehicle 2 moves forward. Until the entire vehicle 2 passes over the step 506 and the lift at the rear is eliminated (time t28), the magnetic intensity measured by the rear magnetic sensor array 4R gradually increases and changes to approach the reference intensity R.

[0059] As the central magnetic sensor array 4C transitions to a floating state at time t27, it moves from being close to the upper road surface 500 to facing the lower road surface 500 with a gap between them. When the central magnetic sensor array 4C faces the lower road surface 500, the magnetic intensity measured by the central magnetic sensor array 4C decreases rapidly.

[0060] The state in which the central part of vehicle 2 is separated from the road surface 500 of the lower step continues as long as the rear of vehicle 2 is on the step 506 and vehicle 2 is tilted downwards from the front. During this time, the magnetic intensity measured by the central magnetic sensor array 4C remains below the reference intensity R. As vehicle 2 moves forward and the downward tilt of vehicle 2 becomes less pronounced, the distance between the central magnetic sensor array 4C and the road surface 500 gradually decreases, and as a result, the magnetic intensity measured by the central magnetic sensor array 4C gradually increases. Then, at time t28, when the rear of vehicle 2 lands on the lower step, the magnetic intensity measured by the central magnetic sensor array 4C returns to the reference intensity R.

[0061] The temporal changes in magnetic intensity measured by the magnetic sensor array 4F·C·R when passing over undulations on path 5 (Figures 9, 11, 13, and 15) can be replaced with positional changes in the direction of travel of path 5, as shown in Figures 16, 18, 20, and 22. Figure 16 shows the positional changes in magnetic intensity measured by the magnetic sensor array 4F·C·R when (1) crossing a ridge. Figure 18 shows the positional changes in magnetic intensity measured by the magnetic sensor array 4F·C·R when (2) crossing a valley. Figure 20 shows the positional changes in magnetic intensity measured by the magnetic sensor array 4F·C·R when (3) going over a step. Figure 22 shows the positional changes in magnetic intensity measured by the magnetic sensor array 4F·C·R when (4) going down a step.

[0062] (1) When crossing a ridge Figure 16 illustrates the positional changes in magnetic intensity measured by the magnetic sensor array 4F·C·R along path 5, which includes the ridge 501 that vehicle 2 crosses. Position P11 in the figure is half the length of vehicle 2, relative to position P12, which is the peak of the ridge 501 (reverse position). Position P13 is half the length of vehicle 2, past position P12, which is the peak of the ridge 501 (advancing position).

[0063] In the section from position P11 to position P12, the rear magnetic sensor array 4R moves away from the road surface 500. Therefore, the magnetic intensity measured by the rear magnetic sensor array 4R decreases in this section. In the section from position P12 to position P13, the front magnetic sensor array 4F moves away from the road surface 500. Therefore, the magnetic intensity measured by the front magnetic sensor array 4F decreases in this section.

[0064] In Figure 16, the sections where the magnetic intensity measured by the front magnetic sensor array 4F decreases are indicated by upward-sloping hatching. Similarly, the sections where the magnetic intensity measured by the rear magnetic sensor array 4R decreases are indicated by downward-sloping hatching. The sections indicated by upward-sloping hatching are unique locations where the distance between the front magnetic sensor array 4F and the road surface 500 is greater than the sensor mounting height. The sections indicated by downward-sloping hatching are unique locations where the distance between the rear magnetic sensor array 4R and the road surface 500 is greater than the sensor mounting height. The sensor mounting height is the mounting height of the magnetic sensor array 4 relative to a flat road surface, and is the distance between the magnetic sensor array 4 and the road surface 500 when the vehicle 2 is located on a flat surface.

[0065] In the route system 1 of this example, as shown in Figure 17, an overlay tape 51P is attached to the magnetic tape 51 in the section from position P11 to position P13. The overlay tape 51P, which is an example of a magnetic component, is a magnetic tape for overlaying, and is a magnetic tape cut from the continuous strip-shaped magnetic tape 51 before laying. By overlaying the overlay tape 51P, if two magnetic tapes 51 are stacked, the magnetic strength acting on the magnetic sensor array 4F·R can be increased, and the decrease in magnetic strength measured by the magnetic sensor array 4F·R can be compensated for. If the magnetic strength measured by the magnetic sensor array 4F·R is sufficient, the risk that the detection reliability of the magnetic tape 51 will be affected by the lifting of the front or rear of the vehicle 2 can be suppressed.

[0066] Depending on the specifications and control method of vehicle 2, for example, only the front magnetic sensor array 4F may be used. In such cases, it is advisable to apply the overlapping tape 51P to the section from position P12 to position P13. Alternatively, for example, only the rear magnetic sensor array 4R may be used. In such cases, it is advisable to apply the overlapping tape 51P to the section from position P11 to position P13.

[0067] (2) When crossing a valley Figure 18 illustrates the positional changes in magnetic intensity measured by the magnetic sensor array 4F·C·R along a path that includes the valley 502 traversed by vehicle 2. Position P15 in the figure is half the length of vehicle 2 before position P16, which is the deepest point of the valley 502. Position P17 is half the length of vehicle 2 past position P16, which is the deepest point of the valley 502.

[0068] In the section from position P15 to position P17, which includes position P16, the deepest part of valley 502, the central magnetic sensor array 4C moves away from the road surface 500. Therefore, in this section, the magnetic intensity measured by the central magnetic sensor array 4C decreases. The magnetic intensity measured by the central magnetic sensor array 4C gradually decreases from position P15, reaches a minimum at position P16, and then gradually increases, returning to the reference intensity R at position P17. On the other hand, the magnetic intensity measured by the front magnetic sensor array 4F and the rear magnetic sensor array 4R is maintained at approximately the reference intensity R in the section from position P15 to position P17, which is before and after valley 502.

[0069] In Figure 18, vertical hatching indicates the sections where the magnetic intensity measured by the central magnetic sensor array 4C decreases. These sections, indicated by vertical hatching, are unique locations where the distance between the central magnetic sensor array 4C and the road surface 500 is greater than the sensor mounting height.

[0070] In the route system 1 of this example, as shown in Figure 19, an overlay tape 51P is attached to the magnetic tape 51 in the section from position P15 to position P17. By attaching the overlay tape 51P to the magnetic tape 51, the magnetic strength acting on the central magnetic sensor array 4C can be increased, compensating for the decrease in magnetic strength measured by the magnetic sensor array 4C. If the magnetic strength measured by the magnetic sensor array 4C is sufficient, the risk of the detection reliability of the magnetic tape 51 being affected by the lifting of the middle section of the vehicle 2 when crossing the valley 502 can be suppressed. Note that if the vehicle 2 is equipped with only one of the front or rear magnetic sensor arrays 4F·R, there is little need to lay the overlay tape 51P in the section spanning both the front and rear of the valley 502.

[0071] (3) When going over a step Figure 20 illustrates the positional changes in magnetic intensity measured by the magnetic sensor array 4F·C·R along path 5, which includes a step 505 that vehicle 2 drives over. Position P21 in the figure is half the length of vehicle 2 before the step 505 at position P22. Position P23 is half the length of vehicle 2 past the step 505 at position P22.

[0072] In the section from position P21 to position P22, the rear magnetic sensor array 4R and the central magnetic sensor array 4C move away from the road surface 500. Therefore, the magnetic intensity measured by the magnetic sensor arrays 4C·R decreases in this section. Also, in the section from position P22 to position P23, the front magnetic sensor array 4F moves away from the road surface 500. Therefore, the magnetic intensity measured by the front magnetic sensor array 4F decreases in this section.

[0073] In Figure 20, the section where the magnetic intensity measured by the front magnetic sensor array 4F decreases is indicated by upward-sloping hatching. The section where the magnetic intensity measured by the rear magnetic sensor array 4R decreases is indicated by downward-sloping hatching. The section where the magnetic intensity measured by the central magnetic sensor array 4C decreases is indicated by vertical hatching. Note that in the same figure, the section where the magnetic intensity measured by the rear magnetic sensor array 4R decreases and the section where the magnetic intensity measured by the central magnetic sensor array 4C decreases coincide, and the downward-sloping hatching and vertical hatching are superimposed.

[0074] In the route system 1 of this example, as shown in Figure 21, an overlay tape 51P is attached to the magnetic tape 51 in the section from position P21 to position P23. By attaching the overlay tape 51P to the magnetic tape 51, the magnetic strength acting on the magnetic sensor array 4F·C·R can be increased, and the decrease in magnetic strength measured by the magnetic sensor array 4F·C·R can be compensated for. If the magnetic strength measured by the magnetic sensor array 4F·C·R is sufficient, the risk that the detection reliability of the magnetic tape 51 will be affected by the lifting of the vehicle 2 from the road surface 500 can be suppressed.

[0075] (4) When going down a step Figure 22 illustrates the positional changes in magnetic intensity measured by the magnetic sensor array 4F·C·R along path 5, which includes a step 506 that vehicle 2 descends. Position P25 in the figure is half the length of vehicle 2 before the step 506 at position P26. Position P27 is half the length of vehicle 2 past the step 506 at position P26.

[0076] In the section from position P25 to position P26, the rear magnetic sensor array 4R moves away from the road surface 500. Therefore, the magnetic intensity measured by the magnetic sensor array 4R decreases in this section. Also, in the section from position P26 to position P27, the front magnetic sensor array 4F and the central magnetic sensor array 4C move away from the road surface 500. Therefore, the magnetic intensity measured by the front magnetic sensor arrays 4F·C decreases in this section.

[0077] In Figure 22, the section where the magnetic intensity measured by the front magnetic sensor array 4F decreases is indicated by upward-sloping hatching. The section where the magnetic intensity measured by the central magnetic sensor array 4C decreases is indicated by vertical hatching. Furthermore, the section where the magnetic intensity measured by the rear magnetic sensor array 4R decreases is indicated by downward-sloping hatching. Note that in the same figure, the section where the magnetic intensity measured by the front magnetic sensor array 4F decreases and the section where the magnetic intensity measured by the central magnetic sensor array 4C decreases coincide, and the upward-sloping hatching and vertical hatching are superimposed.

[0078] In the route system 1 of this example, as shown in Figure 23, an overlay tape 51P is attached to the magnetic tape 51 in the section from position P25 to position P27. By attaching the overlay tape 51P to the magnetic tape 51, the magnetic strength acting on the magnetic sensor array 4F·C·R can be increased, and the decrease in magnetic strength measured by the magnetic sensor array 4F·C·R can be compensated for. If the magnetic strength measured by the magnetic sensor array 4F·C·R is sufficient, the risk that the detection reliability of the magnetic tape 51 will be affected by the lifting of the vehicle 2 from the road surface 500 can be suppressed.

[0079] As described above, in the route system 1 of this example, specific locations have been identified where the distance between the magnetic sensor array 4 and the road surface 500 increases due to a lifting state in which the front or rear of the vehicle 2 lifts up. In these specific locations, two layers of magnetic tape 51 are attached.

[0080] In the route system 1 of this example, the magnetic strength of the magnetic tape 51 is stronger at specific locations where the distance between the magnetic sensor array 4 and the road surface 500 increases. Therefore, even if the vehicle 2 is lifted off the ground, there is little risk of insufficient magnetic strength being measured by the magnetic sensor array 4. If the magnetic strength measured by the magnetic sensor array 4 is sufficient, the magnetic tape 51 can be detected with high reliability even when the vehicle is lifted off the ground.

[0081] In this example, a continuous strip of magnetic tape 51 is used as the magnetic component laid along path 5, and the magnetic strength is increased by stacking two magnetic tapes 51. However, the number of magnetic tapes 51 stacked may be three or more. Although magnetic tape is used as an example, individual magnetic markers may also be used. The magnetic markers may be columnar permanent magnets or sheet-shaped permanent magnets. If columnar magnetic markers are used, the magnetic strength can be increased by stacking two or more in series. If sheet-shaped magnetic markers are used, the magnetic strength acting on the surroundings can be increased by stacking two or more sheets.

[0082] In this example, the magnetic strength is increased by layering two magnetic tapes 51 at specific locations where the distance between the magnetic sensor array 4 and the road surface 500 increases. Alternatively, two or more types of magnetic tapes 51 with different magnetic strengths may be used. In this case, magnetic tapes 51 with high magnetic strength should be laid at specific locations along the path 5, while magnetic tapes 51 with low magnetic strength should be laid at locations where the distance between the magnetic sensor array 4 and the road surface 500 remains the same as the sensor mounting height. The same applies when using magnetic markers as magnetic components; it is advisable to prepare two or more types of magnetic markers with different magnetic strengths.

[0083] This example describes a method for identifying unique locations where the distance between the magnetic sensor array 4 and the road surface 500 increases by measuring the magnetic intensity using the magnetic sensor array 4 while the vehicle 2 is in motion. Alternatively, unique locations where the distance between the magnetic sensor array 4 and the road surface 500 increases can be identified by measuring the distance using a distance measuring sensor, or by identifying locations where a lifting state occurs by processing 3D data representing the undulations of the route and specification data of the vehicle 2.

[0084] This example illustrates a situation where the magnetic strength acting on the magnetic sensor array 4 from magnetic components such as the magnetic tape 51 decreases when vehicle 2 travels along an uneven path 5. For example, when vehicle 2 travels with one side mounted on an embankment, as shown in Figure 24, or when vehicle 2 travels with its vehicle straddling a ditch, as shown in Figure 25, the distance between the magnetic sensor array and the road surface increases, which may reduce the magnetic strength acting on the magnetic sensor array. The locations illustrated in Figures 24 and 25 are also unique locations, and it is advisable to increase the magnetic strength by overlapping the magnetic tape 51P with the magnetic tape 51.

[0085] As a reference example outside the scope of the technical concept of the present invention, it is also possible to change the process for detecting magnetic components such as the magnetic tape 51 depending on whether or not it is a singular location in the path 5. For example, in the process of detecting the magnetic tape 51 by applying a threshold to the physical properties related to magnetism, it is also possible to set a smaller threshold at singular locations compared to locations where the distance of the magnetic sensor array 4 from the road surface 500 remains the same as the sensor mounting height. In this case, even if the magnetic intensity acting from the magnetic tape 51 decreases, the magnetic tape 51 can be detected with high reliability. Alternatively, since the difficulty of detecting magnetic components such as the magnetic tape 51 increases at singular locations, it is also effective to utilize the continuous strip shape of the magnetic tape 51. For example, it is also possible to incorporate into the detection process the premise that the lateral position of the magnetic tape detected at two points in time that are one or the other before will not deviate significantly. With such a premise, the magnetic tape 51, which has decreased in magnetic intensity and is difficult to detect, can be detected with high reliability. Furthermore, for example, it is also possible to predict the lateral position of the magnetic tape 51 based on the control amount of the vehicle 2's driving control, such as speed or yaw rate. If the lateral position of the magnetic tape 51 can be predicted, the detection target area can be limited, and the magnetic tape 51, which is difficult to detect, can be detected with high reliability.

[0086] Although specific examples of the present invention have been described in detail as shown in the examples above, these examples only disclose an example of the technology covered by the claims. Needless to say, the claims should not be interpreted restrictively based on the configuration or numerical values ​​of the specific examples. The claims encompass technologies obtained by various modifications, changes, or combinations of the above examples using prior art or the knowledge of those skilled in the art. [Explanation of Symbols]

[0087] 1. Routing System 2 vehicles (tracked vehicles, crawler vehicles) 2B vehicle 20 Control circuits 30 Detection Circuit 21L·R Crawler 4. Magnetic sensor array (magnetic measurement circuit) 4L Front magnetic sensor array 4C Central magnetic sensor array 4R Rear magnetic sensor array 43 Detection Processing Unit 5 routes 501 Ridge 502 Valley Steps 505, 506 51 Magnetic tape (magnetic components) 51P Overlapping Tape (for magnetic components)

Claims

1. A track system in which magnetic components that exert a magnetic field on their surroundings are laid along a path on which a tracked vehicle travels, wherein the tracked vehicle is equipped with one or more magnetic detection circuits for detecting the magnetic components, A path system for a tracked vehicle, characterized in that, in a specific location where the distance between one or more of the magnetic detection circuits and the road surface increases during the operation of the tracked vehicle, the magnetic strength of the magnetic component is greater than at the location where the distance during the operation of the tracked vehicle is equal to the mounting height.

2. A path system for a tracked vehicle according to claim 1, wherein the magnetic component is a magnetic tape or a magnetic marker in the form of a pieceped sheet, and two or more of the magnetic components are arranged in overlapping layers at the specific location.

3. A path system for a tracked vehicle, according to claim 1 or 2, wherein the unique location includes a location where, in response to the undulations of the road surface, either the front or rear side of the tracked vehicle lifts off the road surface, thereby increasing the distance between the magnetic detection circuit and the road surface.

4. A method for laying magnetic components that exert a magnetic field on their surroundings along a path on which a tracked vehicle travels, wherein the tracked vehicle is equipped with one or more magnetic detection circuits for detecting the magnetic components, A method for laying magnetic components, characterized in that, while the tracked vehicle is in motion, a specific location is identified where the distance between one or more of the magnetic detection circuits and the road surface is greater than the mounting height, which is the height of the magnetic detection circuit relative to a flat road surface, and at the specific location, the magnetic strength of the magnetic component is made greater than at the location where the distance between the magnetic components is greater than at the mounting height while the tracked vehicle is in motion.

5. A method for laying magnetic components, according to claim 4, wherein the magnetic component is a magnetic tape or a magnetic marker in the form of individual pieces or sheets, and two or more of the magnetic components are arranged in overlapping layers at the specific location.

6. A method for laying magnetic components, wherein the unique location includes a location in which, in accordance with the undulations of the road surface, either the front or rear side of the tracked vehicle lifts off the road surface, thereby increasing the distance between the magnetic detection circuit and the road surface.

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