JPH0692897B2 - Unit mileage correction device for carrier vehicles - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a device for correcting a unit traveling distance required for measuring a traveling distance of a carrier vehicle.

[Conventional technology]

In general, the traveling of a carrier vehicle has conventionally performed position control and speed control based on output data of the number of rotations of wheels such as an encoder.

However, in such a conventional traveling control device for a carrier vehicle,
If there is no difference between the calculated mileage calculated from the output data of the encoder etc. and the actual mileage, accurate travel control can be performed, but if the diameter of the drive wheel changes due to long-term use, etc., There is a difference between the actual travel distance and the calculated travel distance calculated by an encoder or the like, resulting in a problem that the travel control cannot be performed accurately.

Therefore, the transport vehicle is actually driven in a reference straight line section on the travel route provided with the guiding means, the rotation speed of the drive wheel is detected, and the accurate diameter of the drive wheel is calculated by this and the distance of the reference section. Then, correct the unit mileage data so that the calculated mileage calculated from the rotational speed of the drive wheels matches the actual mileage, grasp the accurate mileage, and control the traveling of the guided vehicle. I have to.

A conventional unit travel distance correction device for this purpose is to provide a reference distance measurement section on a straight line route, to actually run the transport vehicle in a straight line within the section to obtain the amount of wheel rotation, and to calculate the wheel distance from the straight line distance of the measurement section. A means for calculating the travel distance per unit amount of rotation is adopted.

[Problems to be Solved by the Invention]

In the prior art, it was necessary to guide the vehicle by a physical guide means such as an optical tape guide line or dead reckoning in order to run the carrier in the reference section, so that the device and the control method were complicated. Further, in the prior art, it was considered that the carrier vehicle accurately follows the traveling route in the reference distance measurement section and goes straight, but in reality, the carrier vehicle does not point in the route direction at the starting point, In order to follow the route from the state, the actual traveling locus is not a straight line but a circle or an almost circular arc to move forward. For this reason, there is a disadvantage in that there is a difference between the reference distance measurement section length and the actual travel path length, which causes an error in the travel distance per unit rotation amount of the wheel.

In view of such a point, the present invention can accurately calculate the travel distance per unit rotation amount of the wheels even when the guide means is not required and the travel locus of the guided vehicle in the reference distance measurement section draws an arc. An object of the present invention is to provide a unit traveling distance correction device for a carrier vehicle.

[Means for Solving the Problems]

A unit traveling distance correction device for a guided vehicle of the present invention to achieve the above object, a signal indicating the start point and the end point of a reference distance measurement section provided on the traveling route, a device for detecting this signal, and a wheel. A device for detecting a rotation amount, and a unit travel distance measuring device for a transport vehicle for calculating a travel amount per unit rotation amount of a wheel by obtaining a rotation amount of a wheel in a reference distance measurement section from these output data, A device for detecting the posture angle and lateral displacement of the transport vehicle at the start point and the end point of the measurement section, and a computing device for computing the travel locus of the transport vehicle and its distance from the output data are provided, and the travel distance and the wheel rotation by this are provided. A unit travel distance correction device for a carrier vehicle, comprising a unit travel distance correction calculation device for calculating a travel distance per unit rotation amount of a wheel from an amount.

[Work]

The attitude angle and the lateral displacement of the carrier are detected at each of the start point and the end point of the measurement period. In this way, the actual travel path length of the transport vehicle is calculated. As a result, it is possible to accurately know the travel distance of the wheel per unit rotation amount.

〔Example〕

 The present invention will be described below based on the embodiments shown in the drawings.

FIG. 3 shows an example of the travel route of the transport vehicle 1. A reference distance measurement section A is set at an appropriate position on the travel route 3. Reference numeral 4 is its start point and 5 is its end point, which are provided with signal generators 4a and 5a, respectively. In the figure, 1 indicates the section length.

The transport vehicle 1 is provided with the unit traveling distance correction device 10 of the present invention. The correction device 10 includes a signal detection device 11 that receives a signal when passing through the start point 4 and the end point 5, a rotation amount detection device 12 of a wheel (preferably a drive wheel) 2, the start point 4 and the end point 5.
A unit for correcting and calculating the traveling angle per unit amount of rotation of the vehicle based on the posture angle of the carrier vehicle 1 and the lateral displacement amount (both of which will be described later) detection device 13 and travel path length calculation device 14 It comprises a mileage correction calculation device 15.

Next, the posture angle and the lateral displacement of the carrier 1 at the start point 4 and the end point 5 will be described with reference to FIG.

In a measurement section A including a start point 4 and an end point 5, a carrier vehicle (only the rear wheels and the shaft center are shown for simplicity) 1 has its center point 6 on the travel route 3 and its shaft center 7 on the route. It is difficult to fit the above correctly. Therefore, at the starting point 4, the center point 6 is displaced laterally with respect to the travel route 3 by a distance of d1, and the axis 7 is inclined with respect to the travel route 3 by θ1. From this state, the steering angle is kept constant and the vehicle is moved forward. As a result, at the end point 5, the center point 6 becomes the traveling route 3
On the other hand, it is assumed that the shaft 7 is laterally displaced a distance d2 and the axis 7 is inclined at an angle θ2 with respect to the travel route 3. These angles and displacements are detected by the detection device 13. A in the figure,
b is an imaginary line drawn parallel to the travel route 3.

Therefore, the traveling procedure between the start point 4 and the end point 5 of the transport vehicle 1 is such that the traveling route 3 is first skewed and reaches the route 3,
Then, the vehicle travels obliquely away from the route, and as an approximate value of this, the actual traveling locus B is an arc and its center point is C.

When the measurement section length on this traveling locus B is l1, l1
Is calculated from the following formula. However, R is the radius of the arcuate travel locus B.

In FIG. 2, (d2-d1-ltan θ1) cos θ1 = R [1-cos (θ2-θ1)]
…… (1) From formula (1) Since R can be calculated from the equation (2), l1 = R (θ2-θ1) (3) can be calculated.

The above calculation is performed by the travel path length calculation device.

Next, the calculation method of the mileage per unit rotation amount of the wheel
A description will be given based on the flowchart in the figure.

When the transport vehicle 1 traveling on the travel route 3 shown in FIG. 3 reaches the starting point 4, the signal detecting device 11 detects the starting point signal and starts the operation of the wheel rotation amount detecting device 12, and at the same time, the posture angle lateral displacement detecting device. The starting angle θ1 and the lateral displacement amount d1 at the starting point are detected by 13.

Next, when the transport vehicle 1 reaches the end point 5, the signal detection device 11 detects the end point signal, stops the operation of the wheel rotation amount detection device 12, and holds the rotation amount data. At the same time, the posture angle lateral displacement detection device 13 detects the posture angle θ2 and the lateral displacement amount d2 at the end point.

The posture angles θ1 and θ2, the lateral displacement amounts d1 and d2, and the measurement section length 1 are input to the traveling locus length calculation device 14, and the device 14 calculates the traveling locus length l1 from the above-described calculation formula (3).

The travel locus l1 and the rotation amount data held in the wheel rotation amount detection device 12 are input to the unit travel distance correction calculation device 15, the travel distance per unit rotation amount of the wheel is calculated, and accurate data is obtained. In order to obtain it, the same route can be traveled a predetermined number of times, and the data can be averaged to obtain the unit travel distance of the transport vehicle.

In this embodiment, the left and right wheels 2 of the transport vehicle 1 are connected and rotated, and at that time, assuming that the wheel 2 is located at the center point 6, the unit traveling distance is calculated and controlled as described above. Show. When rotating the left and right two wheels independently,
Since the inner and outer wheels do not travel on the traveling locus B, it is preferable to correct each of the inner and outer wheels when accurate traveling control is performed. An embodiment in that case is shown in FIG.

In the figure, 2a is the inner ring, 2b is the outer ring, T is the distance between the inner and outer rings (tread), and lR and lL are the measurement section lengths of the inner and outer rings.

As a result, the calculation formula is the same as that calculated in the previous example, Can be calculated, and the traveling distance per unit amount of rotation of the inner ring 2a (or the outer ring 2b) can be measured in the above manner.

Although the reference distance measurement section A is a straight line in any of the embodiments, it is needless to say that it is not limited to a straight line according to the present invention.

〔The invention's effect〕

According to the present invention, it is possible to detect the posture angle and the lateral displacement amount of the carrier vehicle at the start point and the end point in the reference distance measurement section without providing the guide means on the travel route, and thereby to detect the actual travel path length of the carrier vehicle. Since the distance is calculated and the travel distance per unit rotation amount of the wheels of the transport vehicle is calculated, the error can be reduced as compared with the conventional method in which the distance of the measurement section is used as a reference. Further, in the reference distance measurement section, since it is sufficient to drive the steering wheel with a constant steering angle, it is possible to easily control the traveling of the guided vehicle within the measurement section.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is a block diagram of a unit mileage correction device of the present invention, FIG. 2 is an explanatory view of a trajectory length calculation principle, and FIG. 3 is a travel route of a carrier vehicle. FIG. 4 is an operation flow chart, and FIG. 5 is an explanatory diagram of a running locus length calculation method for the left and right two wheels. 1 is a carrier vehicle, 2 is a wheel, 3 is a traveling route, 4 is a starting point, 5 is an ending point, 10 is a unit traveling distance correcting device, 11 is a signal detecting device,
Reference numeral 12 is a rotation amount detection device, 13 is a posture angle lateral displacement detection device, 14 is a traveling locus length calculation device, 15 is a unit traveling distance correction calculation device, and A is a reference distance measurement section.

Claims (1)

[Claims] 1. A signal indicating the start and end points of a reference distance measurement section provided on a travel route, a device for detecting this signal, a device for detecting the amount of rotation of wheels, and a reference distance based on output data of these signals. In a unit traveling distance measuring device for a transport vehicle, which calculates a travel distance per unit rotation amount of a wheel by obtaining a rotation amount of a wheel in a measurement section, a posture angle of the transport vehicle at a start point and an end point of the reference distance measurement section, and a lateral direction. A device for detecting a directional displacement and a calculation device for calculating a traveling locus of the carrier vehicle and its distance from output data of the detection device are provided. Based on the traveling distance and the rotation amount of the wheel, the travel per unit rotation amount of the wheel is performed. A unit traveled distance correction device for a carrier, comprising a unit traveled distance correction calculation device for calculating a distance.