JP2004005324A - Transport equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate setting for passing route of a transport equipment, and to enable self-propelling on the passing route. <P>SOLUTION: This transport equipment has a traveling means 4 for the transport equipment, a control means 3 for controlling driving condition of the traveling means, a measuring means 1 for measuring traveling rate of the transport equipment, and a transport equipment traveling rate recording means 2. In the first setting condition, traveling rate is recorded by the recording means, and in the second setting condition, drive of the traveling means is controlled in response to the traveling rate data recorded by the recording means. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a transport device having a basic function of reciprocating between two defined points along a defined route.
[0002]
[Prior art]
Representative methods that have been realized or proposed to guide the movement of the automatic guided vehicle are described below. (JP-A-11-265211)
The first method is to provide a guiding path using physical characteristics such as a magnetic field, an optical field, an electric field, or the like, or a guiding path using mechanical characteristics such as rails, guide grooves, and the like, and the transport device moves along the guiding path. How to
[0003]
The second method is a method in which a transport device has map data in the vicinity of a movement path and moves while confirming its own position on the map data by an environment recognition unit such as a mounted photographing device or a non-contact length measuring device. .
[0004]
[Problems to be solved by the invention]
Such a conventional guidance method has the following problems.
[0005]
In the first method, it is necessary to provide facilities including physical characteristics or mechanical characteristics to be used for guidance in a moving route. This has a problem that time and economic restrictions on the setting and construction of the moving route are large, and changing the moving route is not easy. Further, particularly in home use and office use, it is a serious problem that the appearance is impaired by the guidance equipment.
[0006]
The second method requires a relatively large-capacity recording unit or environment recognition unit for holding map data, and is a large-scale apparatus. Also, a method of acquiring and configuring map data and a method of formulating a route to a destination point are required, which results in a complicated and enormous software configuration as compared with the present invention. Further, when a difference occurs between the map data and the actual map due to movement of a trash can, chair, cabinet, or the like, there is a problem that an arrival point is different from a destination point or cannot be moved.
[0007]
According to the present invention, it is possible to easily set a moving route of a transfer device and to travel independently on the moving route.
[0008]
[Means for Solving the Problems]
The present invention has been made to solve the aforementioned problems.
[0009]
According to the first aspect of the present invention, there is provided a moving unit, a control unit for controlling the driving of the moving unit, a measuring unit for measuring the moving amount, and a recording unit for directly or converting and recording the moving amount data obtained by the measuring unit. Means, the transport device having at least two setting states of a first setting state and a second setting state, in the first setting state, directly or converting the movement amount data obtained by the measuring means The transfer device is characterized in that, in the second setting state, the control means drives and controls the moving means in accordance with the movement amount data recorded in the recording means. I do.
[0010]
According to a second aspect of the present invention, in the transport device according to the first aspect, in the second setting state, the control unit drives the moving unit according to the moving amount data recorded in the recording unit. While controlling, the moving amount data is obtained by the measuring unit, and the controlling unit compares the moving amount data recorded by the recording unit with the moving amount data obtained by the measuring unit. The transfer device is characterized in that the movement data is corrected.
[0011]
According to a third aspect of the present invention, in the transport device according to the first or second aspect, in addition to the movement amount data recorded in the recording means, the movement amount data obtained by the measurement means is directly or directly transferred. The data is converted and additionally recorded in the recording means.
[0012]
Further, the invention according to claim 4 is the transport device according to claim 1 or claim 2, wherein the operation means uses the movement amount data recorded in the recording means and the movement amount data obtained by the measurement means. A new movement route is calculated, and part or all of the movement amount data recorded in the recording means is rewritten to a new movement route.
[0013]
Further, the invention according to claim 5 is the transfer device according to claim 1 or 2, wherein in the second setting state, one or more stop states are set during the traveling. Features.
[0014]
In addition, the invention of claim 6 is characterized in that the moving means is constituted by at least three wheels, and the measuring means is a wheel rotation angle detecting means provided on at least two of the wheels. The transfer device according to claim 1.
[0015]
Further, in the invention according to claim 7, the measuring means is an image photographing means for capturing an optical characteristic of the floor, an image recording means for recording an image captured by the image photographing means, and an image capturing means for capturing the image captured by the image photographing means. 6. An image comparing means for comparing a captured image with an image previously recorded in the image recording means and detecting a movement amount from a difference between the images. Transport device.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the transport device of the present invention will be described with reference to the drawings.
[0017]
FIG. 1 is a block diagram showing the principle configuration of the transport device according to the embodiment.
[0018]
The measuring means 1 is a device for measuring a difference between a position and a direction at a certain point of the transfer device and a position and a direction at a time immediately before the transfer device as movement amount data, and captures a two-dimensional movement of the transfer device. This difference can be set in various ways, such as at equal time intervals or at equal movement distances. In any case, if the interval is made small, the movement route can be measured finely. The recording means 2 and the control means 3 capture the movement amount data as they are, or convert them into movement distances and direction change amounts via a conversion means (not shown) provided immediately after the measurement means 1. Conveyed to.
[0019]
The recording means 2 sequentially records the movement amount data transmitted from the measuring means 1 and holds the data as a series of data. In response to a request from the control means 3, a function of sequentially sending the series of data to the control means from the beginning or from the end is provided.
[0020]
The control means 3 controls the driving of the moving means 4 in accordance with the movement data sent from the recording means 2 and the actual movement amount data transmitted from the measuring means 1 so as to reproduce the movement data held in the recording means 2. Move the transport device.
[0021]
The moving means 4 includes the measuring means 1, the recording means 2, the control means 3, and other necessary devices (such as a power supply) and a load, and accelerates, decelerates, and changes the traveling direction (steering) according to a drive signal from the control means 3. And move.
[0022]
FIG. 2 is a signal block diagram at the time of follow-up, which is defined as a period during which the transfer device moves by an external force for setting a movement route. The external force includes, in addition to pushing and pulling by a person, a case where the moving unit 4 is driven by a remote control operation or the like to move the transport device. At the time of follow-up, when the transport device moves by an external force, the measuring means 1 measures the movement amount, sends them to the recording means 2 at predetermined intervals, and sequentially records the movement amount data on the recording means 2.
[0023]
With this configuration, an arbitrary moving route can be easily set by setting the transport device in the driven mode at the departure point and pulling it from there to the target point.
[0024]
FIG. 3 is a signal block diagram at the time of traveling defined as a period during which the transport device moves along the set movement route.
[0025]
When the control means 3 receives a departure command during traveling after setting the movement route, the movement amount data is read from the recording means 2 in the reverse order of the order in which the movement amount data was recorded, and the movement means 4 is read in order to reproduce the movement amount data. And the transfer device moves. Along with this, the measuring means 1 measures the actual amount of movement and transmits it to the control means 3. The control means 3 calculates the difference between the movement amount data read from the recording means 2 and the actual movement amount measured by the measurement means 1 as a movement error, and corrects the difference by reading the next movement amount read from the recording means 2. The movement error is subtracted from the data to obtain corrected movement amount data. The control means 3 controls the driving of the moving means 4 so as to reproduce the corrected movement amount data, and the transfer device moves. The drive error is similarly determined for this section and thereafter, and drive control is performed in accordance with the corrected movement amount data for correcting the movement error. This is a measure to prevent the accumulation of movement errors, and as a result, highly accurate movement with a small position error at the arrival point has become possible.
[0026]
By repeating these series of operations until the movement amount data ends, the transport device returns to the starting point. Thereafter, similarly, if the moving amount data is read out in the order in which the moving amount data is recorded, and the moving means 4 is drive-controlled to reproduce the data, the transport device moves from the starting point to the target point. That is, the reciprocating operation of the moving route can be performed any number of times.
[0027]
As described above, the position error is small and the movement with high accuracy is enabled. However, there are cases where the position error cannot be ignored and it is desired to make a correction, or there is a case where the target point or the starting point is to be changed. In these cases, it is necessary to change the movement route data recorded in the recording means 2.
[0028]
FIG. 4 is a conceptual diagram of movement route data, which is an aggregate of a series of movement amount data, recorded in the recording unit 2. The moving route data after setting the moving route is shown in FIG. When the transport device travels along the movement route, arrives at a target point or a departure point, stops, and then corrects the position, the transport device is moved by an external force such as pushing or pulling by human power. At that time, after the transport device stops at the target point or the departure point, when the measuring means 1 detects the movement of the transport device, the measuring means 1 measures the amount of movement and adds a new travel route data in addition to the recorded travel route data. The travel route data is additionally recorded. When a correction is made at the target point, additional recording is sequentially performed on the recorded travel route data at the target point side, and when a correction is made at the departure point, additional recording is sequentially performed at the recorded travel route data at the departure point side. I do. As a result, a new departure point or target point is set. (See FIG. 4B)
When the new target point is corrected in the direction of the departure point as shown in FIG. 5, the above-described recording method results in an inefficient moving operation in which the vehicle goes past the new target point and returns according to the additional data. In order to prevent this, when the moving route is corrected, as shown in FIG. 6, the recording means 2 sends the moving route data and the additional data to the calculating means 5, and the calculating means 5 determines the starting point based on them. Calculates a reasonable new travel route from to the new target point, replaces the portion different from the travel route data with the correction data, and corrects it as new travel route data in the recording means 2 in the form shown in FIG. Record. Since the transport device moves according to the new travel route data, it is possible to return from the new target point along the reasonable route to the starting point and from there to the new target point along the reasonable route. . Although the correction at the target point has been described here, the same applies to the correction at the departure point.
[0029]
At the time of setting the movement route, if the stop point data is recorded in the recording means 2 in addition to the movement route data by a switch operation or a method of stopping the transport device for a certain period of time or the like, the stop point can be set on the movement route. It is possible. During traveling, the control means 3 controls the driving of the moving means 4 according to the moving route data, and stops the moving means 4 according to the woven stop point data. When the re-moving operation is performed, the control unit 3 controls the driving of the moving unit 4 according to the subsequent moving route data. This makes it possible to stop the transport device not only at the departure point and the target point, but also at any position along the movement route.
[0030]
FIG. 7 shows a moving means of the transport device used in an example showing one embodiment according to the present invention.
[0031]
The base 11 of the transport device has two drive wheels 12 and 13 that are driven independently of each other, and a driven wheel 14 that can be freely steered, and can be moved by rotating them.
[0032]
The wheel 15 of the left driving wheel 12 includes a speed reducer, is rotatably supported on a top surface of a gear box 16 fixed to the base 11, and also serves as an output shaft of the speed reducer. A DC motor 17 shaft is directly connected to the human-powered shaft of the speed reducer, and an optical encoder 18 constituting the measuring means 1 for detecting the rotation angle of the DC motor 17 shaft is provided. Since the rotation of the DC motor 17 shaft and the rotation of the axle 15 of the drive wheel 12 are restrained to each other via the speed reducer, when the DC motor 17 rotates, the drive wheel 12 is rotated at a speed obtained by multiplying the rotation speed by the speed reduction ratio of the speed reducer. When the drive wheel 12 rotates, the DC motor 17 rotates at a speed obtained by multiplying the rotation speed by the reciprocal of the reduction ratio. Therefore, the output value of the optical encoder 18 that detects the rotation angle of the DC motor 17 axis is proportional to the moving distance of the drive wheel 12 if the drive wheel 12 does not slip at the ground.
[0033]
When the transfer device is moved by an external force, the reduction ratio of the reduction gear is suppressed to 1/40 in order to prevent the driving wheels 12 from slipping at the ground contact point, and is generated via the reduction gear from the friction torque of the DC motor 17 and the like. The design was made so that the load torque on the axle 15 did not exceed the torque for rotating the drive wheel 12 caused by the friction between the drive wheel 12 and the floor.
[0034]
The drive system on the right side also has a drive wheel 13, an axle 19, a gear box 20, a DC motor 21, and an optical encoder 22, and is configured and has the same functions as the drive system on the left side. The left axle 15 and the right axle 19 are arranged on a straight line so as to be coaxial.
[0035]
The driven wheel 14 uses a rotatable caster, and can move in any direction while supporting a load.
[0036]
An intermediate point between the ground points of the drive wheels 12 and 13 is represented by a point A representing the position of the transport device, a distance (tread) between the ground points is represented by B, and a moving distance of the drive wheel 12 is L in a minute section. Assuming that the respective encoders 18 and 22 detect that the moving distance of the drive wheel 13 is R, the moving distance S of the point A and the direction change K of the transport device during this period are expressed by the following equations.
[0037]
S = (L + R) / 2
K = (LR) / B (radian)
Further, the moving distance L of the driving wheel 12 and the moving distance R of the driving wheel 13 can be inversely calculated from the following formula based on the moving distance S of the point A and the direction change K of the transport device.
[0038]
L = S + BK / 2
R = S-BK / 2
The same calculation can be performed for the subsequent minute sections one after another.
[0039]
To record the movement amount data at the time of follow-up, the moving distance L of the driving wheel 12 and the moving distance R of the driving wheel 13 are sequentially recorded in the recording means 2 for each minute section, or the calculation of the above equation is executed, and the point A is calculated. Is converted into the moving distance S and the direction change K of the transfer device, and S and K are sequentially recorded in the recording means 2. In the present embodiment, a calculation is performed to calculate the movement amount S of the point A every time the movement distance L of the drive wheel 12 or the movement distance R of the drive wheel 13 changes, and when it reaches a predetermined value, the minute section ends. Is determined, the direction change K of the transfer device is obtained, and the process proceeds to the next minute section. In this way, since the movement amount S of the point A is a constant value, there is no need for recording, and the movement amount data can be recorded by recording only the direction change K of the transport device, and the storage capacity can be reduced by half. Alternatively, if the storage capacity is the same, the movement amount data can be recorded at twice the resolution.
[0040]
During traveling, the previously recorded movement amount data is read out, and the control means 3 supplies electric power to the DC motors 17 and 21 to rotate the drive wheels 12 and 13 accordingly. At the same time, the actual movement amount is obtained from the output signals of the encoders 18 and 22.
[0041]
When the road surface condition changes due to running, the running resistance changes every moment. Therefore, the actual movement amount did not always match the read movement amount data. In order to correct this movement error, the movement error is subtracted from the next movement amount data read from the recording means 2 to obtain corrected movement amount data, and the control means 3 drives the driving wheels 12 and 13 to rotate in accordance with the corrected movement amount data. Method.
[0042]
As described above, the present inventors have devised and realized a moving method with a small position error and high accuracy, but this is because there is no relative slip between the wheel provided with the measuring means for knowing the moving amount and the floor surface. It is assumed. However, it was confirmed that slight slippage occurred depending on the situation, although this was within a range where there was no practical problem. The measuring device shown in FIG. 8 was used for a transport device requiring further movement accuracy.
[0043]
The image photographing means 6 such as a CMOS or CCD camera which is attached to the bottom of the transfer device so that the floor surface can be photographed substantially at the center thereof has an extremely fast shutter speed. It can capture instantaneous images of the floor to the same extent. When the floor surface is viewed finely, the floor surface has various optical characteristics for each location, and the location can be identified. The image photographing means 6 captures an instantaneous image of the floor surface at certain intervals, and transmits the image data to the image recording means 7 and the image comparing means 8. The image comparing means 8 compares the image data with the immediately preceding image data recorded in the image recording means 7 and obtains the movement amount of the transport device at the camera lens position during that period.
[0044]
FIG. 9A is an example of a simplified instantaneous image of the floor taken just before FIG. 9B. When the two images are compared by the image comparing means 8, a moving distance S and a direction change K are obtained as shown in FIG. 9C. As can be understood from this example, the overlapping portion of the two images is indispensable for comparison, and it is possible to eliminate erroneous measurement by obtaining an overlapping area that is preferably half or more of the image area. . The photographing time interval for obtaining the necessary overlapping area is determined by the moving speed of the transport device, and the actual photographing time interval must be set so as not to exceed it.
[0045]
According to the method of obtaining the movement amount from the floor image, the slip of the wheel does not affect the measurement of the movement amount.
[0046]
The present invention relates to a transport device having a basic function of reciprocating along a predetermined route between a predetermined two points, but at least a plurality of the two-point routes, If a route is set so that one end point is common to the end points of the other two-point routes, and all the movement route data of the plurality of two-point routes are recorded, a relatively complicated configuration as shown in FIG. The transfer device can be moved to any end point on the movement route even on a simple movement route.
[0047]
【The invention's effect】
As described above, according to the first aspect of the present invention, it is possible to easily set the movement route of the transfer device, and the transfer device can travel independently on the movement route.
[0048]
According to the second aspect of the present invention, it is possible to move the transport device with high accuracy, with a small positional error at the arrival point.
[0049]
According to the invention of claim 3, correction and resetting of the departure point and the destination point can be easily performed.
[0050]
According to the invention of claim 4, after the start point or the target point is corrected or reset, the transport device can move along a reasonable route.
[0051]
According to the invention of claim 5, the transport device can be stopped at an arbitrary position on the movement route other than the departure point and the destination point.
[0052]
According to the invention of claim 6, the measuring means can be realized with a simple configuration.
[0053]
According to the invention of claim 7, it is possible to measure the movement amount of the transfer device with high accuracy even on a slippery floor surface.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a principle configuration of a transport device according to an embodiment of the present invention.
FIG. 2 is a signal block diagram at the time of follow operation in the embodiment of the present invention.
FIG. 3 is a signal block diagram during traveling in the embodiment of the present invention.
FIG. 4 is a conceptual diagram of movement route data recorded in a recording unit.
FIG. 5 is a diagram illustrating an example of a method of correcting movement route data.
FIG. 6 is a signal block diagram when moving route data is corrected.
FIG. 7 is a bird's-eye view showing a moving unit and a measuring unit according to the embodiment.
FIG. 8 is a signal block diagram of a measuring unit using a floor image of the present embodiment.
FIG. 9 is a diagram illustrating an example of a measurement method using a floor image.
FIG. 10 is a diagram illustrating a moving route obtained by combining a plurality of two-point routes.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Measuring means 2 Recording means 3 Control means 4 Moving means 5 Computing means 6 Image photographing means 7 Image recording means 8 Image comparing means 11 Bases 12 and 13 of a conveyance device Drive wheels 14 Follower wheels 15 and 19 Axles 16 and 20 Gearbox 17, 21 DC motor 18, 22 Optical encoder

Claims (7)

A moving unit, a control unit for controlling the driving of the moving unit, a measuring unit for measuring the moving amount, and a recording unit for recording the moving amount data obtained by the measuring unit directly or after converting the data, In the transport device having at least two setting states of the setting state and the second setting state, during the first setting state, the movement amount data obtained by the measuring means is directly or converted and recorded in the recording means. And a control device for controlling the driving of the moving means in accordance with the moving amount data recorded in the recording means in the second setting state. The transport device according to claim 1, wherein in the second setting state, the control unit drives and controls the moving unit in accordance with the moving amount data recorded in the recording unit, and the measuring unit controls the driving of the moving unit. The moving amount data is obtained, the control unit compares the moving amount data recorded in the recording unit with the moving amount data obtained by the measuring unit, and corrects the moving amount data recorded in the recording unit. A transfer device characterized by the above-mentioned. 3. The transport device according to claim 1, wherein, in addition to the movement amount data recorded in said recording means, movement amount data obtained by said measuring means is directly or converted and added to said recording means. A transport device for recording. 3. The transport device according to claim 1, wherein the arithmetic unit calculates new movement data based on the movement amount data recorded on the recording unit and the movement amount data obtained by the measurement unit. A transport device characterized in that part or all of the movement amount data recorded in the recording means is rewritten with new movement amount data. 3. The transfer device according to claim 1, wherein one or more stop states are set during the traveling in the second set state. The said movement means is comprised by at least three wheels, and the said measurement means is a wheel rotation angle detection means which can each detect the rotation angle of at least two wheels among the wheels. 6. The transport device according to 5. The measuring unit includes: an image capturing unit that captures an optical characteristic of a floor surface; an image recording unit that records an image captured by the image capturing unit; an image captured by the image capturing unit; The transport device according to claim 1, further comprising: an image comparison unit configured to compare a recorded image with the image and detect a movement amount based on a difference between the images.

Images