JP2015170284A - Forklift type unmanned carrier vehicle, control method of the same, and control device of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a forklift type unmanned carrier vehicle capable of reducing the risk of an accidental contact characteristic of a forklift, a control method and a control device of the same.SOLUTION: A forklift type unmanned carrier vehicle 1 comprises: a plurality of first obstacle detectors 2, 3, and 4 disposed around a vehicle body 1B and detecting a surrounding environment of the vehicle body 1B; a detection area storage unit storing in advance obstacle detection areas A surrounding the vehicle body 1B and set depending on a driving situation including a traveling speed, a steering direction, and a transfer operation of the vehicle body 1B; and an obstacle detection safety control unit selecting one obstacle detection area A depending on an actual driving situation of the vehicle body 1B, transmitting information on the selected obstacle detection area A to the plurality of first obstacle detectors 2, 3, and 4, and controlling the vehicle body 1B to stop traveling if it is detected that an obstacle is present in the selected obstacle detection area A.

Description

  The present invention relates to a forklift type automatic guided vehicle, a control method thereof, and a control device.

The automatic guided vehicle can realize the intrinsic safety that the human and the automatic guided vehicle do not come into contact with each other by separating the traveling paths of the automatic guided vehicle and the automatic guided vehicle with a fence. it can.
However, in actual operation, the automatic guided vehicle has the same merit as the tracked vehicle if the road is separated from the person or the road is surrounded by a fence. This hinders operations with diversity. Therefore, it has been operated by taking measures to reduce interpersonal contact risks and obstacles in the event of contact by means of contact safety detection using bumper switches and functional safety means using object relative distance detection means using laser, infrared or ultrasonic waves. ing.

General automated guided vehicles have a history of operating at speeds of 60 m / min or less, which is considered safe, and the risk of accidents was low.
On the other hand, the ratio of forklift trucks is increasing at about 10% of the sales results of automated guided vehicles in Japan. A general automatic guided vehicle and an automatic forklift are completely different from each other in terms of vehicle shape, running performance, and dynamic behavior during running due to differences in applications and the presence or absence of load transfer. In addition, manned forklifts are also subject to a lot of interpersonal contact occupational accidents, and there is a need for a method for avoiding interpersonal contact that matches the characteristics of forklifts different from general automatic guided vehicles.

  In order to avoid contact with a person of an automated guided vehicle, JIS D6802 Automated guided vehicle system—General safety rules require the installation of an approach detection device that avoids contact with a person and collision with surrounding objects. The following patent documents 1-4 are examples of what corresponds to an approach detection device.

Japanese Patent Laid-Open No. 11-305837 Japanese Unexamined Patent Publication No. 63-180883 Japanese Patent Laid-Open No. 5-189039 JP-A-9-26826

  On the other hand, as forklifts, there are counterbalance forklifts, straddle forklifts, pallet stacking trucks, side forklifts, reach forklifts, walkie forklifts, etc. depending on the shape according to JIS D6201; To do.

  Unlike a general automatic guided vehicle, a fork lifts a fork from a vehicle body and loads and transports the load on the fork. Therefore, loading the load creates a space occupied by the load in front of the vehicle body. There is a risk of contact between the fork protruding from the vehicle body and a person.

  In addition, the steering wheel is steered by the rear wheel, the steering wheel is steered at an angle of 90 degrees or more, and the turning behavior of the inner wheel and the outer wheel is as follows. The fork tips have different trajectories, and the risk of interpersonal contact is greater than that of a general automated guided vehicle.

  In view of the above circumstances, an object of the present invention is to provide a forklift type automatic guided vehicle, a control method thereof, and a control device capable of reducing the object contact risk inherent to the forklift.

  In order to achieve the above object, a forklift type automatic guided vehicle according to the first aspect of the present invention is arranged around a vehicle body, and includes a plurality of first obstacle detection devices for detecting the surrounding environment of the vehicle body, A detection area storage unit in which an obstacle detection area around the vehicle body set in accordance with a driving situation including a traveling speed, a steering direction, and a transfer operation is stored in advance, and an actual traveling speed of the vehicle body, a steering direction, An obstacle detection safety control unit that selects the obstacle detection area in accordance with the driving situation including the transfer operation and sends information on the selected obstacle detection area to the plurality of first obstacle detection devices. The obstacle detection safety control unit performs control to stop the vehicle body when the first obstacle detection device detects that there is an obstacle in the selected obstacle detection area. ing.

  The forklift type automatic guided vehicle according to the second aspect of the present invention includes a guidance control device that controls unmanned traveling of the vehicle body, and a first obstacle detection device that detects obstacles around the vehicle body. An obstacle detection safety control unit that determines whether or not the obstacle exists in a region, combines the determined signal and the signal of the guidance control device, and performs stop control of the vehicle body according to the driving state of the vehicle body And.

  A control device according to the third aspect of the present invention is a control device used to control the forklift type automatic guided vehicle according to the first aspect of the present invention.

  A control device according to the fourth aspect of the present invention is a control device used to control the forklift type automatic guided vehicle according to the second aspect of the present invention.

  The control method for a forklift type automatic guided vehicle according to the fifth aspect of the present invention is a method for controlling the forklift type automatic guided vehicle according to the first aspect of the present invention.

  A control method for a forklift type automatic guided vehicle according to the sixth aspect of the present invention is a method for controlling the forklift type automatic guided vehicle according to the second aspect of the present invention.

  ADVANTAGE OF THE INVENTION According to this invention, the forklift type automatic guided vehicle which can reduce the objective contact risk intrinsic | native to a forklift, its control method, and a control apparatus are realizable.

(a) is a side view showing a forklift type automatic guided vehicle according to an embodiment of the present invention, (b) is a top view, and (c) is a rear view. The top view which shows the range which the sensor of a fork type automatic guided vehicle detects an obstruction. The conceptual diagram which shows the structure of the control part of a fork type automatic guided vehicle. The top view showing the coordinate of the positional relationship of a back obstacle, a back obstacle sensor, and a front obstacle sensor. The top view which shows an example of the area | region which a back obstruction sensor and a left and right front obstruction sensor detect. The top view which shows the monitoring area | region when the fork type automatic guided vehicle is drive | working the curve. (a)-(i) is a top view which shows nine typical patterns as arrangement | positioning of the monitoring area | region of a detection area. The top view which shows switching of the monitoring area | region A during driving | operation of a fork type automatic guided vehicle. The top view which shows the example of the various monitoring area | regions of a fork type automatic guided vehicle. The top view which shows the example of the various monitoring area | regions of a fork type automatic guided vehicle. The top view which shows the example of the various monitoring area | regions of a fork type automatic guided vehicle. The top view which shows the example of the various monitoring area | regions of a fork type automatic guided vehicle. The top view which shows the example of the various monitoring area | regions of a fork type automatic guided vehicle. The top view which shows the example of the various monitoring area | regions of a fork type automatic guided vehicle. The figure which shows the outline | summary flow of an obstacle detection safety control. The flowchart which shows the selection control of the monitoring area | region in obstacle detection safety control. The flowchart which shows the protection control around the vehicle body in obstacle detection safety control. The flowchart which shows the obstruction detection process of the vehicle body back of a fork type automatic guided vehicle.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
The configuration of a forklift type automatic guided vehicle 1 (hereinafter referred to as a fork type automatic guided vehicle 1) according to an embodiment in which a reach type electric forklift is automated is shown in FIG. Fig.1 (a) is a side view which shows the forklift type automatic guided vehicle of embodiment based on this invention, FIG.1 (b) is a top view, FIG.1 (c) is a rear view.

  In the fork-type automatic guided vehicle 1, left and right front wheels w1 and w1 that rotate only in the front-rear direction are rigidly attached to an outrigger 10 and a drive wheel and a left rear wheel w2 that is a steering wheel and a rear wheel w3 that is a caster are connected. It is attached to the vehicle body 1B (see FIG. 1 (c)).

The fork type automatic guided vehicle 1 includes a fork 5 for loading a load on a front portion, a backrest 5b for raising and lowering the fork 5, and a mast 5m for guiding the backrest 5b.
At the rear part of the fork type automatic guided vehicle 1, a driving unit 6 provided with a traveling motor for steering and driving the left rear wheel w <b> 2 is provided, and a stand 7 is provided at the top of the driving unit 6. A headlamp 7p for recognizing the fork type automatic guided vehicle 1 is installed on the top of the stand 7. Note that the fork type automatic guided vehicle 1 is provided with an emergency stop button (not shown) for emergency stop in an emergency.

<Sensor>
A guidance sensor 8 a is installed on the top of the stand 7. Based on the environment map showing the layout in the building created by the guidance sensor 8a, guidance control of the fork type automatic guided vehicle 1 is performed, and automatic driving is performed unattended.
The rear bumper 1b of the fork type automatic guided vehicle 1 is provided with a bumper switch 1s for detecting that an object, a person, or the like has come into contact (collision). As the bumper switch 1s, a tape-shaped pressure-sensitive switch or the like that occupies a small space is used.

An interpersonal detection sensor 8b for three-dimensional position recognition is installed on the drive unit 6.
FIG. 2 is a top view showing a range in which the sensor of the fork type automatic guided vehicle 1 detects an obstacle.
The interpersonal detection sensor 8b detects an obstacle in the stop control region T and an obstacle in the deceleration control region G when the fork type automatic guided vehicle 1 moves backward.
FIG. 2 shows a case where the deceleration control region G has a structure K such as a column or a wall. Further, in the drawings after FIG. 2, the brackets 3b and 4b of the rear and front obstacle sensors 2, 3, and 4 are partially omitted.
The human detection sensor 8b detects an obstacle in three dimensions, and the position information of the obstacle on the environmental map is clearly indicated by replacing the position information of the obstacle by the human detection sensor 8b with the information on the horizontal plane. .

  As shown in FIG. 1B, a rear obstacle sensor 2 that is a two-dimensional distance measuring device that detects an obstacle behind the vehicle body 1B and the side of the vehicle body 1B is installed at the lower rear portion of the vehicle body 1B. . In addition, a pair of front obstacle sensors 3 and 4 for detecting obstacles on the front side and the side of the vehicle body are installed in front of the vehicle body 1B above the left and right outriggers 1O1 and 1O2. As shown in FIG. 1 (a), the rear and front obstacle sensors 2, 3, and 4 of the two-dimensional distance measuring device are installed by transposing up and down in order to detect an obstacle near the floor surface.

  If the obstacle can be detected at a position close to the floor, the rear and front obstacle sensors 2, 3, and 4 do not necessarily have to be transposed up and down. For example, laser light is used for the rear / front obstacle sensors 2, 3, and 4, and the distance from the detection object is measured based on the time when the object is reflected and returned to the detection object (such as an obstacle).

The rear / front obstacle sensors 2, 3, 4 are installed so as to detect an obstacle with a height of about 100 to 250 mm from the floor surface Y. With this detection height, it is possible to detect the presence of a person even when the person standing or the person is falling. Thereby, an obstruction etc. can be detected reliably.
The height of the rear / front obstacle sensors 2, 3, 4 is most preferably 200 to 230 mm from the floor surface Y. Here, it is assumed that the rear and front obstacle sensors 2, 3, and 4 are attached at a height of about 230 mm.

  As shown in FIGS. 1 (a) and 1 (b), the front obstacle sensors 3 and 4 attached to the front outriggers 1O1 and 1O2 are provided with left and right protection so that they are not damaged by being stepped on or hit by a load. The mounting brackets 3b and 4b are formed of a protective steel plate having a thickness of about 5 mm, and both the mounting bracket and the device protection are used.

  The left protective mounting bracket 3b has a mounting portion 3b1 attached to the left outrigger 1O1, and a protective portion 3b2 having a shape covering the front obstacle sensor 3 continuously from the mounting portion 3b1. The front obstacle sensor 3 is attached to the attachment portion 3b1.

  Similarly, the right protective mounting bracket 4b has a mounting portion 4b1 attached to the right outrigger 1O2, and a protective portion 4b2 shaped so as to cover the front obstacle sensor 4 continuously from the mounting portion 4b1. The front obstacle sensor 4 is attached to the attachment portion 4b1.

  The front obstacle sensors 3 and 4 detect an obstacle having a height of about 230 mm on the front and side of the vehicle body at the position where the fork 5 is lowered. Further, an obstacle having a height of about 230 mm on the front and side including the lower side of the fork 5 at a position where the fork 5 is raised above the front obstacle sensors 3 and 4 is detected.

The rear obstacle sensor 2 detects an obstacle having a height of about 230 mm behind the fork-type automatic guided vehicle 1 and on the rear left and right sides.
The rear and front obstacle sensors 2, 3, and 4 are areas that are not detected by the deceleration control area G and the stop control area T, that is, monitoring areas A that are set separately from the areas (G, T) (see FIG. 2). Detect that there is an obstacle.

  The fork-type automatic guided vehicle 1 is usually driven backward (reversed). This is because the forward traveling in which the steering wheel and the left rear wheel w2 of the driving wheel are not arranged makes the followability of the vehicle body 1B worse, and the agile traveling according to the intention is impossible. That is, the control is more stable when the left rear wheel w2 of the steering wheel and the drive wheel is in the traveling direction. For these engineering reasons, the forward direction moves only at low speed (does not run).

  The rear / front obstacle sensors 2, 3, and 4 use a distance measuring device such as a general-purpose two-dimensional laser distance meter. The rear obstacle sensor 2 and the front obstacle sensors 3 and 4 may be any sensors as long as the functions of a two-dimensional distance measuring device described later can be performed.

In addition, the fork type automatic guided vehicle 1 has a speed sensor (see FIG. 3) for detecting the traveling speed, a steering angle sensor (see FIG. 3) for detecting the steering direction, and the position of the load loaded on the fork 5 is confirmed. A limit switch (not shown) is provided.
The position of the load placed on the fork 5 is detected with a limit switch that the fork has been inserted into the pallet up to a specified position at the end of the fork.

<System configuration>
FIG. 3 is a conceptual diagram showing a configuration of a control unit of the fork type automatic guided vehicle.
The fork type automatic guided vehicle 1 includes a vehicle body control unit 1C, an obstacle detection safety control unit 1S, and an emergency stop safety control unit 1T as a control system.

  The vehicle body control unit 1C causes the fork-type automatic guided vehicle 1 to travel along a predetermined route, brakes, and raises and lowers the fork 5 based on information from the guidance sensor 8a (see FIG. 1). Further, the vehicle body control unit 1C decelerates the fork type automatic guided vehicle 1 when detecting an obstacle in the deceleration control region G (see FIG. 2) based on the information of the human detection sensor 8b, and stops the stop control region T. When the obstacle is detected in (see FIG. 2), the fork type automatic guided vehicle 1 is stopped. Thereby, it is possible to avoid the fork type automatic guided vehicle 1 from colliding with a person or an object.

  The emergency stop safety control unit 1T shuts off the power supply to the brake after stopping the fork type automatic guided vehicle 1 with the brake when the bumper switch 1s detects a collision and when the emergency stop button is pressed.

  The obstacle detection safety control unit 1S registers in advance a plurality of monitoring areas (protection areas) A (see FIG. 2; details will be described later) corresponding to various conditions in a table or the like. 4, it is determined that the obstacle is in the monitoring area (protection area) A. When the emergency stop safety control unit 1T determines that the obstacle is in the monitoring area (protection area) A, the emergency stop safety control unit 1T stops the fork type automatic guided vehicle 1 by cutting off the power of the travel motor and braking with a brake.

  The obstacle detection safety control unit 1S appropriately transmits an output signal to monitor whether the electrical contacts are welded, to execute a self-diagnosis program, to monitor the state of the internal bus, and to be internally configured in two systems. We are striving for early detection of failures by conducting self-diagnosis to determine whether there is a failure.

<Rear obstacle sensor 2 and front obstacle sensors 3, 4>
The rear and front obstacle sensors 2, 3, and 4 use sensors that detect a range of 270 degrees in the distance scanning range on the horizontal plane. Note that the detection range is not limited to 270 degrees, and other angle ranges may be detected.

When the rear / front obstacle sensors 2, 3, and 4 are installed upside down, the relationship between each sensor and the obstacle P in the rear is represented by the relationship shown in FIG. FIG. 4 is a top view showing the coordinates of the positional relationship between the rear obstacle, the rear obstacle sensor, and the front obstacle sensor.
The rear obstacle sensor 2 distributes around the y1 axis and monitors a range of 270 degrees. The front obstacle sensor 3 monitors the range of 270 degrees by sorting around the y3 axis. The front obstacle sensor 4 monitors the range of 270 degrees by sorting the y2 axis as the center.

For example, the sensor mounting position
Rear obstacle sensor 2 coordinates (X1, Y1) = (0, 0)
Coordinates (X2, Y2) = (− 1.706, 0.478) of right front obstacle sensor 4
Coordinates (X3, Y3) = (− 1.706, −0.478) of the left front obstacle sensor 3
The case where each is installed will be described.

When the coordinates of the obstacle P 2 are the origin (0, 0) and the coordinates (X, Y) of the obstacle P, the coordinates (X, Y) of the obstacle P and the coordinates (X2) of the right front obstacle sensor 4 are used. , Y2) is expressed by a known coordinate transformation formula.
Similarly, the relationship between the coordinates (X, Y) of the obstacle P and the coordinates (X3, Y3) of the left front obstacle sensor 3 is expressed by a known coordinate conversion formula.

FIG. 5 is a top view illustrating an example of a region detected by the rear obstacle sensor and the left and right front obstacle sensors.
The area where the rear obstacle sensor 2 and the left and right front obstacle sensors 3 and 4 monitor the obstacle is an obstacle in the monitoring area A in a range surrounded by points designated by a plurality of points (P1 to P7). Is detected. The rear obstacle sensor 2 monitors obstacles in a region (monitoring region A) surrounded by points P1, P2, P3, P5, and P6 in the region shown in FIG. The right front obstacle sensor 4 monitors an obstacle in a region (monitoring region A) surrounded by points P4, P5, and P7. The left front obstacle sensor 3 monitors an obstacle in an area (monitoring area A) surrounded by points P8, P9, and P10.

  In this way, the range that each sensor (2, 3, 4) shares is set in a polar coordinate system with one distance value for the same declination (region without two or more distance values). The point can be shared by a plurality of areas, and a monitoring area A for protection around the fork type automatic guided vehicle 1 is set. The monitoring area (protection area) A means an area where the fork-type automatic guided vehicle 1 is emergency-stopped when any of the rear / front obstacle sensors 2, 3, 4 detects an obstacle.

<Monitoring area settings>
The setting of the monitoring area is determined as follows.
When the fork-type automatic guided vehicle 1 travels in one direction (for example, when traveling backward or forward), a braking distance at a speed at which the fork-type automatic guided vehicle 1 travels in one direction is obtained. A distance where the automatic guided vehicle 1 is stopped and does not collide with an obstacle is defined as a monitoring area A. That is, a certain amount of margin is given to the braking distance.

  By setting the traveling speed of the fork type automatic guided vehicle 1, its weight, the weight of the load, the brake braking force, etc., the braking distance is obtained using the equation of motion. In the fork type automatic guided vehicle 1, the traveling speed is classified into four speeds of “very low speed” (very low speed including speed 0), “low speed”, “medium speed”, and “high speed”.

  For example, the deceleration is obtained by dividing the brake braking force by the mass including the load of the fork type automatic guided vehicle 1. Then, the deceleration is time-integrated to obtain the time to stop from an equation equivalent to the speed, and the braking distance is calculated by integrating the deceleration twice with time.

  When the fork-type automatic guided vehicle 1 turns a curve, the braking distance from the speed at which the fork-type automatic guided vehicle 1 travels until the vehicle stops by deceleration of the brake is determined, and the distance with a margin not to collide with an obstacle is set. Here, the margin means that a margin of 10 to 50 cm is taken, for example. The braking distance is theoretically or experimentally determined as described above from the speed of the fork type automatic guided vehicle 1 and the presence or absence of a load.

<Setting the monitoring area when turning>
A method for setting the monitoring area A when the fork type automatic guided vehicle 1 curves will be described.
FIG. 6 is a top view showing a monitoring area when the fork type automatic guided vehicle 1 is traveling on a curve.
For example, a travel distance (braking distance) from a travel speed of 1.00 m / sec to a stop by deceleration of the brake is set to 0.44 m, and a turning radius at the time of curve is 2 m. The angle θ that is bent until the braking distance L is 0.44 m is expressed by the following expression (1) from the relationship between the length of the arc and the angle θ formed by the arc when the turning radius is r.

式(１)より説明した条件では、旋回半径ｒが２ｍで１２．６ｄｅｇを走行し、０．４４ｍの制動距離Ｌをもって停止する。

Under the conditions described from the equation (1), the vehicle travels 12.6 deg with a turning radius r of 2 m and stops with a braking distance L of 0.44 m.

  Therefore, as shown in FIG. 6, the fork type automatic guided vehicle 1 loaded with the load N is curved with a turning radius r of 2 m and an angle θ of 12.6 deg, and a braking distance (arc length) of 0.44 m. The region of the movement locus of the fork type automatic guided vehicle 1 that stops with L is obtained. If the movement trajectory of the fork type automatic guided vehicle 1 based on the braking distance L is used as it is for the monitoring area A, it will come into contact with the obstacle, so that there is some margin in the area in order to avoid contact with the obstacle. The monitoring area A is determined with y1. As described above, the monitoring area A may include the movement trajectory of the fork-type automatic guided vehicle 1 loaded with the load N or the fork-type automatic guided vehicle 1 when the load N is not loaded.

<Nine representative patterns of monitoring area A>
Nine typical patterns for the arrangement of the monitoring area A in the detection area are shown in FIGS.
When the fork-type automatic guided vehicle 1 with the setting number 9 shown in FIG. 7A travels backward at a high speed, the farthest rear point of the rear region Aa1 of the monitoring region A makes an emergency stop at the traveling speed. When performing (braking), that is, the power of the driving device for traveling is cut off, and the value of the braking distance that is decelerated by the brake and stopped is set so as not to collide with an obstacle.

  When traveling along a curve as shown in setting numbers 3, 5, 6, and 8 shown in FIGS. 7B, 7C, 7D, and 7E, the curve is set as shown in FIG. A range including the locus of the fork type automatic guided vehicle 1 when traveling at the speed is set. FIGS. 7B and 7D show a case where the fork-type automatic guided vehicle 1 turns leftward toward the rear, and FIGS. 7C and 7E show that the fork-type automatic guided vehicle 1 faces backward. The case of turning right is shown.

  When setting the monitoring area A that is asymmetrical such as setting numbers 3, 5, 6, and 8, the steering angle is set large, and when turning with a small radius of curvature, the rear part is larger than the center of the vehicle body 1B. The movement is a behavior unique to forklifts.

  In this case, in addition to being prone to human entrainment in manned forklifts, generally forklifts are largely turned to enter narrow spaces, but at that time there is a gap between surrounding structures and loads already placed ( There are few gaps. For this reason, the monitoring area A is set asymmetrically so that a gap with the surrounding area can be taken and a range in which interpersonal contact can be protected is set.

  The setting number 4 in FIG. 7 (f) indicates the monitoring area A in which the fork-type automatic guided vehicle 1 moves backward at a low speed, for example. Since the fork-type automatic guided vehicle 1 advances at a low speed toward the rear, a braking distance to the rear is necessary when braking, and therefore the monitoring area A has a larger rear area than a front area. .

  Further, the monitoring area A on the side of the fork-type automatic guided vehicle 1 is a margin area (an area for avoiding collision with an object or person) with respect to an object or person on both sides when traveling backward.

  The setting number 7 in FIG. 7G indicates the monitoring area A in which the fork type automatic guided vehicle 1 travels backward at a low speed. Since the speed of the fork-type automatic guided vehicle 1 is higher than the setting number 4 in FIG. 7 (f), the rear monitoring area Ag1 that is the traveling direction is the rear monitoring that is the traveling direction in FIG. 7 (f). It is set so as to extend rearward from the area Af1.

  The setting number 2 in FIG. 7 (h) represents “being transferred” when a load is loaded on the fork 5. When “load is being loaded” when loading a load onto the fork 5, the load loading side on the front side of the fork type automatic guided vehicle 1 is a monitoring area A in which the area Ah 1 on the front side is not set due to the movement of the load. .

  The setting number 1 in FIG. 7 (i) indicates the monitoring area A when the fork 5 is loaded and unloaded. In setting number 1 in FIG. 7 (i), since the operation is “very low speed” when loading and unloading, a small monitoring area Ai1 is set in the rear area.

表１の「走行速度」とはフォーク型無人搬送車１の走行速度を示す。走行速度「極低速」は、速度０を含む極低速を意味する。
表１の「操舵方向」とはフォーク型無人搬送車１の操舵する方向を示す。表１中の「don’t care」は、フォーク５が動作時で右折左折の操舵方向を問わないことを示す。 <Selection of monitoring area>
Table 1 shows the selection conditions for determining the monitoring area A shown in FIGS.

The “traveling speed” in Table 1 indicates the traveling speed of the fork type automatic guided vehicle 1. The traveling speed “very low speed” means an extremely low speed including zero speed.
The “steering direction” in Table 1 indicates the steering direction of the fork type automatic guided vehicle 1. “Don't care” in Table 1 indicates that the steering direction of the right turn and the left turn does not matter when the fork 5 is operating.

  “Transferring” in Table 1 indicates that the fork 5 is in operation and the load placed on the pallet is being loaded or unloaded from the fork 5. “TRUE” of “Transferring” indicates a state of “Transferring” in which the load placed on the pallet is loaded on or removed from the fork 5. On the other hand, “FALSE” indicates that the fork 5 is not operated and the load placed on the pallet is not placed on the fork 5 or unloaded from the fork 5.

  In the set monitoring area A shown in FIGS. 7 (a) to 7 (i), the obstacle detection safety control unit 1S has a combination of the three conditions shown in Table 1, the traveling speed, the steering direction, and the transfer (transfer operation). The monitoring area A to be monitored is selected according to the condition selection table in Table 1.

  It is determined that the state of the incorrect combination is “abnormal”, and the fork-type automatic guided vehicle 1 is brought to an emergency stop. The illegal combination means that the traveling speed is “very low speed (very low speed including speed 0)” and the fork 5 should be moved up and down, but it should be moving at “medium speed” or “high speed”. You should turn a curve at a low speed or a medium speed, turn a curve at a high speed, and so on. If these three conditions are not satisfied, the traveling speed, the steering direction, and the transfer condition are judged to be an incorrect combination “abnormal”, and the fork type automatic guided vehicle 1 is brought to an emergency stop.

  As shown in Table 1, the first traveling speed is “very low speed (very low speed including 0)”, the steering direction is “don't care”, and “FALSE” is being transferred (not being transferred) In this case, the setting number “1” (see FIG. 7 (i)) is selected. The fork-type automatic guided vehicle 1 travels at an extremely low speed when loading, and the rear monitoring area Ai1 takes a small monitoring area A.

  When the second travel speed is “very low speed”, the steering direction is “don't care”, and the transfer is “TRUE” (transfer), the setting number is “2” (see FIG. 7 (h)). Select. Since the fork type automatic guided vehicle 1 is traveling immediately after the load is loaded, and it is difficult to estimate the state of the place where the load is placed, the front area is set as a monitoring area A where monitoring is not performed.

  When the third travel speed is “low speed”, the steering direction is “right turn”, and the transfer is “FALSE” (not being transferred), the setting number “3” (see FIG. 7B) is selected. . The monitoring area A is a large area on the right rear side, which is the traveling direction of the fork-type automatic guided vehicle 1, and a large area on the left front side.

  When the fourth travel speed is “low speed”, the steering direction is “left turn”, and the transfer is “FALSE”, the setting number “5” (see FIG. 7C) is selected. The monitoring area A is a monitoring area A in which the left rear area, which is the traveling direction of the fork-type automatic guided vehicle 1, is large, and the right front area is large.

  When the fifth travel speed is “low speed”, the steering direction is “straight forward”, and the transfer in progress is “FALSE”, the setting number “4” (see FIG. 7F) is selected. A rear area Af1 that is the traveling direction of the fork type automatic guided vehicle 1 is a large monitoring area A.

  If the sixth travel speed is “low speed”, the steering direction is “do n’t care”, and the transfer is “TRUE”, the incorrect combination is “abnormal”. Since the fork 5 is operated and the load is being transferred to the fork type automatic guided vehicle 1, the traveling speed should be “very low”, but the traveling speed is “low” and too fast. Therefore, there is a possibility that transfer will not be performed smoothly or there is a possibility that various data will be set incorrectly. Therefore, the fork-type automatic guided vehicle 1 is brought to an emergency stop because it is an illegal combination “abnormal”.

  When the seventh travel speed is “medium speed”, the steering direction is “right turn”, and the transfer is “FALSE” (not being transferred), the setting number “6” (see FIG. 7D) is selected. To do. Since the fork-type automatic guided vehicle 1 is “medium speed” and “turns right”, the region on the right side in the traveling direction is larger than the case of “low speed” (see FIG. 7B), and the region on the left front side is larger. The monitoring area A is larger than in the case of “low speed”.

  When the eighth travel speed is “medium speed”, the steering direction is “left turn”, and the transfer is “FALSE”, the setting number “8” (see FIG. 7E) is selected. The left rear region, which is the traveling direction of the fork-type automatic guided vehicle 1, is larger than the case of “low speed” (see FIG. 7C), and the right front region is larger than the case of “low speed”.

  When the ninth travel speed is “medium speed”, the steering direction is “straight forward”, and the transfer is “FALSE”, the setting number “7” (see FIG. 7G) is selected. The rear region Ag1 that is the traveling direction of the fork type automatic guided vehicle 1 is set to be a monitoring region A that is larger than the case of “low speed”.

  If the tenth traveling speed is “medium speed”, the steering direction is “do n’t care”, and the transfer is “TRUE”, it is assumed that the combination is “abnormal”. Since the fork 5 is operated and the load is being transferred to the fork-type automatic guided vehicle 1, the traveling speed should be “very low”, but the traveling speed is too high at “medium speed”. Therefore, there is a possibility that transfer will not be performed smoothly or there is a possibility that various data will be set incorrectly. Therefore, the fork-type automatic guided vehicle 1 is brought to an emergency stop because it is an illegal combination “abnormal”.

  If the eleventh travel speed is “high speed”, the steering direction is “right turn”, and the transfer is “FALSE” (not being transferred), it is assumed that the combination is “abnormal”. Since the fork type automatic guided vehicle 1 is “right turn”, the traveling speed is “high speed” where the traveling speed should be “medium speed”, “low speed”, “very low speed”, and the traveling speed is too fast. For this reason, there is a possibility that the curve cannot be smoothly traveled or there is a possibility that various data are set incorrectly. Therefore, the fork-type automatic guided vehicle 1 is brought to an emergency stop due to an incorrect combination “abnormal”.

  When the twelfth travel speed is “high speed”, the steering direction is “left turn”, and the transfer is “FALSE”, it is assumed that the combination is “abnormal”. Since the fork type automatic guided vehicle 1 is “right turn”, the traveling speed is “high speed” where the traveling speed should be “medium speed”, “low speed”, “very low speed”, and the traveling speed is too fast. For this reason, there is a possibility that the curve cannot be smoothly traveled or there is a possibility that various data are set incorrectly. Therefore, the fork-type automatic guided vehicle 1 is brought to an emergency stop due to an incorrect combination “abnormal”.

  When the thirteenth travel speed is “high speed”, the steering direction is “straight forward”, and the transfer in progress is “FALSE”, the setting number “9” (see FIG. 7A) is selected. The rear area Aa1 that is the traveling direction of the fork-type automatic guided vehicle 1 is set as a monitoring area A that is larger than the case of “medium speed”.

  If the 14th travel speed is “high speed”, the steering direction is “do n’t care”, and the transfer is “TRUE” (transfer), it is assumed that the combination is “abnormal”. Since the fork 5 is operated and the load is being transferred to the fork type automatic guided vehicle 1, the travel speed should be "very low", but the travel speed is too high and too fast. Therefore, there is a possibility that transfer will not be performed smoothly or there is a possibility that various data will be set incorrectly. Therefore, the fork-type automatic guided vehicle 1 is brought to an emergency stop because it is an illegal combination “abnormal”.

  The information in Table 1 is stored in the memory (detection area storage unit) of the obstacle detection safety control unit 1S. The obstacle detection safety control unit 1S is actually input (during operation of the fork type automatic guided vehicle 1). Based on the “traveling speed”, “steering direction”, and “transferring” information, the monitoring area A or “abnormal” of setting numbers 1 to 9 is assigned.

  The information on “traveling speed”, “steering direction”, and “transferring” in Table 1 above is input to the obstacle detection safety control unit 1S (see FIG. 3), the setting number is output, and the monitoring area A is displayed. Specified (see FIG. 7). The “traveling speed” is detected by the speed sensor, and the “steering direction” is detected by the steering angle sensor. Whether or not it is “transferring” is determined by detecting whether or not a current is supplied to a motor (not shown) that operates the fork 5.

Then, the information on the monitoring area A is output from the obstacle detection safety control unit 1S to the rear and front obstacle sensors 2, 3, and 4, and the monitoring area A is monitored by the rear and front obstacle sensors 2, 3, and 4. Carried out.
Further, when an obstacle (such as a person or an object) is detected in the monitoring area A by the rear / front obstacle sensors 2, 3 and 4, it is independent of the vehicle body control unit 1C by the control of the obstacle detection safety control unit 1S. Then, the fork-type automatic guided vehicle 1 is stopped in an emergency. It goes without saying that the information shown in Table 1 can add a new monitoring area A by adding more detailed conditions.

<Switching of monitoring area A during operation of fork type automatic guided vehicle 1>
Next, switching of the monitoring area A during operation of the fork type automatic guided vehicle 1 will be described.
FIG. 8 is a top view showing switching of the monitoring area during operation of the fork type automatic guided vehicle.
While the fork-type automatic guided vehicle 1 is in operation, as shown in FIG. 8, the vehicle travels by switching the monitoring area A in a range to be protected depending on the operation state such as “traveling speed”, “steering direction”, and “transferring”. .

When traveling backward at high speed (I), the monitoring area A is monitored farther away. At the time of low speed reverse movement of (II), only a place near the low speed area of the monitoring area A before the stop is monitored.
(III) is a case where the fork type automatic guided vehicle 1 stops when the direction is changed 90 degrees forward for transfer. When the fork type automatic guided vehicle 1 stops, the monitoring area A is not set.

  During the 90-degree direction change of (IV), in the monitoring area A, the front of the fork type automatic guided vehicle 1 and the side of the fork type automatic guided vehicle 1 are monitored. That is, the monitoring area A monitors the left front area of the left-turn fork type automatic guided vehicle 1 where the fork type automatic guided vehicle 1 moves and the right rear area of the fork type automatic guided vehicle 1 in a large area.

  At (V), before moving the fork 5 in the stacking operation with the reach mechanism forward, it is checked whether there is an obstacle between the load N and the fork 5 in the area Av of the monitoring area A. Thereafter, the reach mechanism is advanced to perform a series of operations of inserting the fork 5 into the pallet, raising the fork 5 and returning the reach mechanism to which the fork 5 is fixed.

(VI) shows a state immediately after the load N is loaded on the fork 5. The monitoring area A immediately after the loading of the load N has no area to monitor because the front side where the fork 5 is located cannot be estimated.
After loading the load N of (VII), the left and right people are monitored by turning in the direction with a large turning radius of 90 degrees to the right. In the monitoring area A of (VII), the turning radius is large. Since the fork-type automatic guided vehicle 1 is placed on the straight path of the fork-type automatic guided vehicle 1 of (VIII) thereafter, the outside of the turning radius of the fork-type automatic guided vehicle 1 is set as a monitoring region A having a larger protection range. .

  In (VIII), after getting on a straight track, the target position is monitored while monitoring the rearward direction of the traveling direction by the monitoring area A having a large rear monitoring range according to the traveling speed of the fork type automatic guided vehicle 1. Drive towards.

<Various monitoring areas A>
Next, various monitoring areas A will be described.
The following monitoring area A is an example of what is added to the monitoring area A in FIG. 7 and Table 1 described above, and it goes without saying that other than the following may be added.

9 to 14 are top views showing examples of various monitoring areas of the fork type automatic guided vehicle.
Depending on the presence / absence of the load on the fork 5 and the shape of the load, as shown in FIGS. 9 to 11, the monitoring area A which is a more complicated protection range can be set. 9 to 11 partially include the monitoring area A of FIG.

FIG. 9A shows a case where the vehicle travels at “very low speed” in the backward straight traveling. Since the traveling speed is “extremely low” during reverse travel when loading and unloading the load, the protection area behind the fork type automatic guided vehicle 1 in the monitoring area A is as small as about 100 mm.
FIG. 9B shows a case where the vehicle travels at “very low speed” in reverse straight traveling. Immediately after loading the load placed on the pallet with the fork 5, it cannot be estimated whether the area ahead of the pallet is an area to be protected.

  On the other hand, when the front obstacle sensors 3 and 4 are at a height at which the load can be detected when the load is placed on the fork 5, the monitoring area A is set to the front, and the fork is placed on the load pallet. It can be used to detect the presence or absence of obstacles and obstacles in the process of inserting the fork 5 at the stage of inserting the fork 5. When an obstacle is detected in the monitoring area A of the front obstacle sensor 3, 4 when handling a load that does not exist or is less than the height of the front obstacle sensor 3, 4 It can be regarded as abnormal.

  FIG. 9C shows a case where the vehicle is traveling at a “very low speed” with a reverse left turn. When the fork type automatic guided vehicle 1 turns left while moving backward in a narrow place, the left and right asymmetric monitoring area A is set. The monitoring area A includes an area Au1 behind the fork-type automatic guided vehicle 1 that is in the traveling direction, an area Au2 on the left side of the rear portion of the fork-type automatic guided vehicle 1 that is opposite to the fork-type automatic guided vehicle 1, and a fork-type The area Am1 on the front right side of the side where the automatic guided vehicle 1 is bent is set to be an area including the fork type automatic guided vehicle 1. The area on the right side of the rear and the area on the left side of the front are not set as the monitoring area A when there is no room.

  FIG. 9D shows a case where the vehicle is traveling at "very low speed" with a reverse right turn. This is a case where the fork type automatic guided vehicle 1 opposite to FIG. 9C turns right while moving backward in a narrow place. In FIG. 9D, as in FIG. 9C, the monitoring area A is asymmetrical on the left and right. The monitoring area A includes an area Au1 behind the fork-type automatic guided vehicle 1 in the traveling direction, an area Au2 on the right side of the rear portion of the fork-type automatic guided vehicle 1 on the opposite side where the fork-type automatic guided vehicle 1 is bent, and a fork-type The area Am1 on the front left side of the side where the automatic guided vehicle 1 is bent is set to be an area including the fork type automatic guided vehicle 1.

  FIG. 9 (e) shows a case where the vehicle travels at a "very low speed" when turning backward. Similarly to FIG. 9 (d), the fork-type automatic guided vehicle 1 turns right while moving backward in a narrow place, but is the case where the traveling speed of the right turn in reverse is low. The monitoring area A has a small area because the traveling speed is low. 9D and 9E, the rear left area and the front right area are not set as the monitoring area A when there is no room.

FIG. 10A shows the case of traveling at “very low speed” (traveling speed 0) in forward straight traveling. In this case, when a pallet loaded with a load is loaded onto the fork 5, the fork type automatic guided vehicle 1 is advanced at an extremely low speed before the fork 5 is inserted into the pallet by the reach mechanism. A monitoring area A is set before the fork 5.
FIG. 10B shows a case where a part of the area in the fork 5 is set as the monitoring area A in the same case as FIG.

FIG. 10 (c) shows a case where the vehicle is traveling at "very low speed" with a left turn forward. Each one-side area of the right rear part and the left front part of the fork type automatic guided vehicle 1 facing the outside of the curve at a minute place is defined as a monitoring area A. The monitoring area A includes the front of the fork 5.
FIG. 10 (d) shows a case of traveling at "very low speed" with a left turn forward. FIG. 10D is the same case as FIG. 10C, but is a case where a part of the area in the fork 5 and the left and right areas of the fork 5 are set as the monitoring area A.

FIG. 10E shows a case where the vehicle travels at a “very low speed” by turning right forward. Each one-side area of the left rear part and the right front part of the fork type automatic guided vehicle 1 facing the outside of the curve at a minute place is defined as a monitoring area A. The monitoring area A includes the front of the fork 5.
FIG. 10 (f) shows a case where the vehicle travels at a "very low speed" with a right turn forward. FIG. 10 (f) is the same case as FIG. 10 (e), but is a case where a part of the area in the fork 5 and the left and right areas of the fork 5 are set as the monitoring area A.

FIG. 11A shows the case of “low speed” in the backward straight line traveling. In the case of a low speed traveling in a straight line in reverse, the protective area behind the fork type automatic guided vehicle 1 in the monitoring area A is as small as about 200 mm.
FIG. 11B shows the case of “low speed” in the backward straight traveling. The fork-type automatic guided vehicle 1 travels in the narrowest area of the vehicle body 1B. The side of the fork-type automatic guided vehicle 1 and the lower side of the pallet placed on the fork 5 are not protected and are not set as the monitoring area A.

FIG. 11C shows the case of “low speed” traveling with a reverse left turn. After the fork type automatic guided vehicle 1 starts running, the fork 5 is included in the monitoring area A before the tip of the fork 5. The monitoring area A behind the fork type automatic guided vehicle 1 in the traveling direction is as small as about 200 mm.
FIG. 11 (d) shows the case of “low speed” traveling in a reverse left turn. When turning backward in a narrow place, set an asymmetrical monitoring area A and pass. The monitoring area A is wider than in the “very low speed” case.

FIG. 11 (e) shows the case of "low speed" traveling with a reverse right turn. After the fork type automatic guided vehicle 1 starts running, the fork 5 is included in the monitoring area A before the tip of the fork 5. The monitoring area A behind the fork type automatic guided vehicle 1 in the traveling direction is as small as about 200 mm.
FIG. 11 (f) shows a case of “low speed” traveling with a reverse right turn. When making a right turn backward in a narrow place, an asymmetrical monitoring area A is set and passed. The monitoring area A is wider than in the “very low speed” case.

  Since the fork 5 is particularly dangerous while the load is being transferred, even if the traveling has stopped, before the fork 5 is taken out, as shown in FIGS. 12 (a) and 12 (b), a person is near the fork type automatic guided vehicle 1 It is also possible to put a safety check at an intermediate stage of the transfer sequence, such as confirming that it is not approaching and proceeding to the next transfer sequence, by appropriately combining detection areas.

FIG. 12A shows the forward confirmation at the time of transfer. This is a safety check immediately before the fork type automatic guided vehicle 1 stops and takes out the fork 5, and the monitoring area A is an area in front of the fork 5.
FIG. 12B shows the forward confirmation during another transfer. This is a safety check immediately before the fork type automatic guided vehicle 1 stops and takes out the fork 5, and the monitoring area A is a case where the area in front of the fork 5 and a part of the area in the fork 5 are used.

FIG. 12C shows the backward confirmation at the time of transfer. In this case, the rear area of the fork type automatic guided vehicle 1 is confirmed as the monitoring area A. During the lifting / lowering operation of the fork 5 at the time of transfer, the area of the pallet transferred by the fork 5 is not the monitoring area A.
FIG. 12 (d) shows the backward confirmation at the time of transfer. This is the same case as FIG. 12 (c), except that the rear rear bumper 1b (see FIG. 1 (a)) is added to the monitoring area A in the monitoring area A of FIG. 12 (c).

  FIG. 13A shows a case of “medium speed” traveling in reverse straight traveling. In the case of reverse straight traveling and a traveling speed of “medium speed”, the monitoring area A behind the fork type automatic guided vehicle 1 in the monitoring area A is as small as about 300 mm.

  FIG. 13 (b) shows a case of “medium speed” traveling in the reverse straight traveling, which is traveling in a narrow space just below the width of the vehicle body 1 </ b> B of the fork type automatic guided vehicle 1. In this case, the area behind the fork-type automatic guided vehicle 1 in the traveling direction is set as the monitoring area A, and the area on the side of the vehicle body 1B and the lower side of the pallet placed on the fork 5 are not set as the monitoring area A.

FIG. 13 (c) shows a case where the vehicle is traveling at a "medium speed" with a reverse left turn. After the fork type automatic guided vehicle 1 starts running, the area before the tip of the fork 5 is included in the monitoring area A.
FIG. 13D shows a case where the vehicle is traveling backward and turning left at “medium speed”. When passing through a narrow place, an asymmetric monitoring area A is set. The monitoring area A is wider than “low speed” traveling.

FIG. 13 (e) shows a case where the vehicle is traveling at a "medium speed" with a reverse right turn. After the fork type automatic guided vehicle 1 starts running, the area before the tip of the fork 5 is included in the monitoring area A.
FIG. 13 (f) shows a case where the vehicle is traveling at a "medium speed" in a reverse right turn. When passing through a narrow place, an asymmetric monitoring area A is set. The monitoring area A is wider than “low speed” traveling.

  FIG. 14A shows the case of traveling at “high speed” in the backward straight traveling. When the fork type automatic guided vehicle 1 travels at “high speed”, the monitoring area A in the traveling direction includes a distance that can be stopped by a brake. With the setting of the monitoring area A described above, the fork type automatic guided vehicle 1 can travel safely at a maximum speed of 180 m / min when no load N is loaded.

  FIG. 14B shows a case where the vehicle travels at a "high speed" in the reverse straight traveling and passes through a narrow place. When the fork-type automatic guided vehicle 1 travels at “high speed”, the monitoring area A in the traveling direction includes a distance that can be stopped by a brake, as in FIG. 14A, but in a narrow place, the side of the vehicle body 1B is This is a case where the monitoring area A is not used.

  By the way, while the load is placed on the fork 5 and transported, there should be no area below the fork 5, but the front obstacle sensors 3 and 4 (see FIG. 1A) When an object is detected, regardless of whether it is a person or an object, the fork type automatic guided vehicle 1 is stopped by regarding it as an abnormal state. In addition to human beings, there are cases where obstacles are the stage before the occurrence of load collapse due to the collapse of the stretch film or the breakage of the stretch film that binds the load on the pallet.

  Furthermore, when performing a spin turn around the center of the vehicle body 1B (see FIG. 1 (b)) and a pivot turn around the front wheel w1 of the driven wheel of the outrigger at 90 degrees steering, the asymmetrical protection area is further increased. be able to.

<Operation of fork type automatic guided vehicle 1>
The fork-type automatic guided vehicle 1 is operated unattended by the following procedure.
When the fork-type automated guided vehicle 1 is used, the user first operates the fork-type automated guided vehicle 1 by manual operation to travel in the building where the fork-type automated guided vehicle 1 is used. Then, the environment in the building is detected by the guidance sensor 8a, and an environment map indicating what the layout in the building is like is created by the vehicle body control unit 1C.

The environment map is newly created when the layout in the building changes or when the building where the fork-type automatic guided vehicle 1 is used changes.
Thereafter, the fork-type automatic guided vehicle 1 is automatically operated by identifying (specifying) its own position based on the information of the environmental map by the operation of the vehicle body control unit 1C.

<Obstacle detection safety control of fork type automatic guided vehicle 1>
Next, the obstacle detection safety control using the monitoring area A of the fork type automatic guided vehicle 1 will be described.
The obstacle detection safety control by the monitoring area A is performed by the control of the obstacle detection safety control unit 1S (see FIG. 3).

FIG. 15 is a diagram showing an outline flow of the obstacle detection safety control.
First, the obstacle detection safety control unit 1S (see FIG. 3) selects the monitoring area A from the information of “traveling speed”, “steering direction”, and “transferring”, and the rear / front obstacle sensor 2, 3 and 4 are set (S101 in FIG. 15). The selection of the monitoring area A in S101 will be described in detail later.

  Subsequently, the rear / front obstacle sensors 2, 3, 4 detect whether there is an obstacle such as a person or an object in the monitoring area A, and if an obstacle is detected in the monitoring area A, the obstacle The information (detection signal) is output to the detection safety control unit 1S, and the fork-type automatic guided vehicle 1 is emergency-stopped by the obstacle detection safety control unit 1S (S102). The protection around the vehicle body 1B in S102 will be described in detail later.

<Selection of monitoring area A>
Next, selection of the monitoring area A in S101 of FIG. 15 will be described with reference to FIG. FIG. 16 is a flowchart showing the selection control of the monitoring area A in the obstacle detection safety control.
The obstacle detection safety control unit 1S obtains information on whether or not the actual “traveling speed”, “steering direction”, and “loading” of the load using the fork 5 (see input shown in Table 1). Then, the operating state of the fork type automatic guided vehicle 1 is monitored (S201 in FIG. 16). In S201, the obstacle detection safety control unit 1S determines each information on whether or not “traveling speed”, “steering direction”, and “transferring” are the speed sensor, the steering angle sensor, and the motor that drives the fork 5, respectively. Get from the current.

Then, the obstacle detection safety control unit 1S determines whether or not the operating state has changed (S202). In the determination of the change of the driving state in S202, a change occurs in any of the input “traveling speed”, “steering direction”, and “transferring” information shown in Table 1. Judgment is made by whether or not it has been switched.
When there is no change in the operation state (No in S202), the process proceeds to S201 and the operation state is monitored.

  On the other hand, when there is a change in the driving state (Yes in S202), the actual “traveling speed”, “steering direction”, and “transferring” information are used to show the information in Table 1 stored in a table or the like. The monitoring area A is selected from the setting numbers 1 to 9 of the setting areas that match the input “traveling speed”, “steering direction”, and “transferring” information. Then, when the selected monitoring area A is set for the rear / front obstacle sensors 2, 3, 4 or when the actual "traveling speed", "steering direction", and "transferring" are incorrect combinations, Fork type automatic guided vehicle 1 is brought to an emergency stop as “abnormal” (S203). Thereafter, the process proceeds to S201, where the obstacle detection safety control unit 1S monitors the operating state of the fork type automatic guided vehicle 1.

<Protection around the body 1B>
Next, protection around the vehicle body 1B in S102 of FIG. 15 will be described with reference to FIG. FIG. 17 is a flowchart showing protection control around the vehicle body 1B in the obstacle detection safety control.
The rear / front obstacle sensors 2, 3, and 4 detect whether or not there is an obstacle in the set monitoring area A (S301 in FIG. 17).

Subsequently, the obstacle detection safety control unit 1S determines whether there is an obstacle in the monitoring area A from the signals of the rear and front obstacle sensors 2, 3, 4 (S302).
When it is determined that there is no obstacle in the monitoring area A (No in S302), the process proceeds to S301, and whether or not the rear / front obstacle sensors 2, 3, 4 have an obstacle in the monitoring area A. Detection is performed.

  On the other hand, when there is an obstacle in the monitoring area A (Yes in S302), the obstacle detection safety control unit 1S shuts off the power supply of the travel motor independently of the vehicle body control unit 1C and uses a fork type brake. The automatic guided vehicle 1 is brought to an emergency stop (S303). Thereafter, when the operation of the fork type automatic guided vehicle 1 is resumed, the process proceeds to S301.

  When the obstacle detection safety control unit 1S detects an obstacle, the fork type automatic guided vehicle 1 is emergency stopped independently of the vehicle body control unit 1C. Therefore, even if the vehicle body control unit 1C breaks down, the emergency stop is performed. It is possible and high safety.

<Processing of Obstacle Detection by Interpersonal Sensor 8b Behind the Car Body 1B of the Fork-type Automated guided Vehicle 1>
Next, with respect to the processing in the case where the person detection sensor 8b detects that there is an obstacle in the deceleration control region G and the stop control region T (see FIG. 2) set behind the fork-type automatic guided vehicle 1, FIG. It explains according to. FIG. 18 is a flowchart showing an obstacle detection process behind the vehicle body of the fork type automatic guided vehicle.

First, the vehicle body control unit 1C determines whether there is an obstacle in the stop control region T (see FIG. 2) based on the detection signal of the human detection sensor 8b (S401 in FIG. 18).
When it is determined that there is an obstacle in the stop control area T (Yes in S401), the vehicle body control unit 1C sets the target speed to “0” to cut off the power supply of the travel motor, and the fork type unmanned with the brake The transport vehicle 1 is brought to an emergency stop (S402). Thereafter, when the operation of the fork type automatic guided vehicle 1 is resumed, the process proceeds to S401.

On the other hand, when it is determined that there is no obstacle in the stop control region T (No in S401), the vehicle body control unit 1C detects that the person detection sensor 8b detects an obstacle in the deceleration control region G (see FIG. 2). It is determined whether or not (S403).
If it is determined that an obstacle has been detected in the deceleration control region G (Yes in S403), it is determined whether there is a correlation with the structure registered in the environmental map (S404).

  When it is determined that the detected obstacle has no correlation with the structure registered in the environmental map (No in S404), the vehicle body control unit 1C sets the target speed of the fork type automatic guided vehicle 1 to the safe speed. Decelerate (S405). Thereafter, the process proceeds to S401.

  On the other hand, when it is determined in S403 that no obstacle is detected in the deceleration control region G (No in S403), the vehicle body control unit 1C performs the obstacle detection process by the human detection sensor 8b to detect the fork type automatic guided vehicle 1. Is decelerated or stopped (S406). Note that the determination in S406 determines whether the vehicle is decelerating or stopping in the obstacle detection process by the human detection sensor 8b.

  This is because, as shown in FIG. 2, a monitoring area A where detection is performed by the rear / front obstacle sensors 2, 3, 4 and a stop control area T and a deceleration control area G where detection is performed by the human detection sensor 8b. Because there are areas that do not overlap, there are cases where the vehicle may start running where it should be stopped unless an independent determination is made.

If it is determined that the fork-type automatic guided vehicle 1 is not decelerating or stopping, and the vehicle is traveling in the set traveling speed (No in S406), the process proceeds to S401.
On the other hand, when it is determined that the fork-type automatic guided vehicle 1 is being decelerated or stopped (Yes in S406), the vehicle body control unit 1C uses the target speed of the fork-type automatic guided vehicle 1 as the travel speed set for the section. (S407), the process proceeds to S401.

If it is determined in S404 that the detected obstacle has a correlation with the structure registered in the environmental map (Yes in S404), the process proceeds to S406.
The above is the obstacle detection process by the human detection sensor 8b.

<Relationship with SLAM technology>
Although an example in which a protection area is provided for each of the obstacle sensors 2 at the rear of each obstacle detection sensor and the left and right front obstacle sensors 3 and 4 has been described, SLAM technology (Simultaneously Localization And Mapping: autonomous) In order to move the robot automatically, generation of an environmental map showing the position information of obstacles and self-position estimation by intelligent robot control technology) When the guiding sensor 8a of the laser distance meter to be used is installed at a height that enables human detection, the following can be performed.

  That is, instead of the human detection sensor 8b, a collision avoidance deceleration process and a stop process are provided outside the monitoring area A which is the protection area described in the present embodiment for the person or obstacle detected on the SLAM side, Safety can be enhanced by hierarchizing the deceleration stop process (see the deceleration control region G and the stop control region T in FIG. 2).

  SLAM deceleration / stop processing areas (deceleration control area G and stop control area T in FIG. 2) may be installed in locations that do not meet the installation requirements for ensuring the safety of automated guided vehicles. Since object avoidance cannot guarantee safety, it is necessary to ensure that it can be stopped reliably with a detection device provided in a place that satisfies safety requirements. This requirement is satisfied by detecting that there is an obstacle in the monitoring area A with the rear obstacle sensor 2 and the left / right front obstacle sensors 3 and 4 and stopping the fork type automatic guided vehicle 1 in an emergency stop. It becomes.

<Share of control>
A control device that performs guidance control to determine whether the distance data output from the obstacle sensor 2 behind the obstacle sensor and the left and right obstacle sensors 3 and 4 are in the monitoring area A as control assignment. When the vehicle body control unit 1C is used, safety may not be ensured against a failure of the control device or a control failure (a factor such as a software bug).

  Therefore, as described above, it is determined whether or not the distance data output from the obstacle sensor 2 behind the obstacle sensor and the left and right front obstacle sensors 3 and 4 are in the monitoring area A. When the obstacle detection safety control unit 1S (see FIG. 3) of the control device independent of the vehicle body control unit 1C) is used, it is possible to protect against a failure or control failure of the guidance control device (vehicle body control unit 1C). Become.

  In addition, distance data output from the rear obstacle sensor 2 and the front obstacle sensors 3 and 4 of the obstacle sensor is preliminarily transmitted to the obstacle sensors (rear obstacle sensor 2, left and right front obstacle sensors 3 and 4). The area to be protected is registered, the judgment is performed by the obstacle sensor, and the obstacle sensor (rear obstacle sensor 2, left / right obstacle sensor 3, 4) has caused a dangerous failure and lost function. Can be recognized, the safety system can be configured mainly by the control device that can determine that the guidance control and the protection determination for the protection area have caused a dangerous failure) and have lost the function. The dangerous failure means a failure that has an effect on a safe function when the failure occurs and becomes unsafe.

  According to the above configuration, when the fork-type automatic guided vehicle 1 travels variously, the monitoring area A that can be safely stopped is set corresponding to each travel, and when there is an obstacle in the monitoring area A, there is no collision. It is possible to stop. Therefore, the fork type automatic guided vehicle 1 can be safely used without colliding with a person or an object while being unattended.

  In addition, the deceleration control region G and the stop control region T (see FIG. 2) detected by the interpersonal detection sensor 8b are layered on the monitoring region A, so that safety can be further improved.

Furthermore, since the stop control by the monitoring area A is performed by the obstacle detection safety control unit 1S independent of the vehicle body control unit 1C of the guidance control device, even if the vehicle body control unit 1C breaks down, Is in the monitoring area A, the fork-type automatic guided vehicle 1 can be safely stopped and controlled.
In addition, when the control device having the function of the obstacle detection safety control unit 1S is configured, the same effect can be obtained.

  From the above, it is possible to realize a forklift type automatic guided vehicle, a control method thereof, and a control device that can reduce the object contact risk inherent to the forklift.

<< Other Embodiments >>
1. In the above-described embodiment, the driving situation in which the monitoring area A of the fork-type automatic guided vehicle 1 is set is exemplified by “traveling speed”, “steering direction”, and “transferring”. It may be configured to include at least one of presence / absence, shape or size of the load, and whether or not the load is deformed. It is also possible to employ other driving conditions. Thus, by appropriately selecting the driving situation and setting the monitoring area A, collision with an obstacle can be avoided and finer safety can be ensured.

2. The present invention can be applied to any modification of a new forklift and the modification of a forklift that is already in operation.

  In addition, this invention is not limited to above-described embodiment, Various embodiments are included. For example, the above-described embodiment is a description of the present invention in an easy-to-understand manner, and is not necessarily limited to one having all the configurations described. For example, a part of the configuration described may be included.

  Moreover, it is possible to replace a part of embodiment form with the structure of other embodiment, and it is also possible to add the structure of other embodiment to the structure of a certain embodiment. Moreover, it is also possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  The application of the present technology is not limited to reach-type forklifts, but can be applied to counterbalance forklifts and side forklifts that perform more complex movements (forklifts with forks coming out and loaded next to them). In addition, even a general automatic guided vehicle can be applied to an automatic guided vehicle in which a robot is mounted on an automatic guided vehicle that performs a complicated operation such as a four-wheel steering type or an automatic guided vehicle that performs an operation that loads or protrudes from a vehicle body. .

1 Forklift-type automated guided vehicle 1B Car body 1C Car body control unit (guidance control device)
1S Obstacle detection safety control unit (control device)
2 Rear obstacle sensor (first obstacle detection device)
3, 4 Front obstacle sensor (first obstacle detection device)
8a Guiding sensor (second obstacle detection device)
8b Interpersonal detection sensor (second obstacle detection device)
A Monitoring area (obstacle detection area)
G Deceleration control area P Obstacle T Stop control area

Claims (15)

A plurality of first obstacle detection devices arranged around the vehicle body for detecting the surrounding environment of the vehicle body;
A detection area storage unit that stores in advance an obstacle detection area around the vehicle body that is set according to a driving situation including a traveling speed of the vehicle body, a steering direction, and a transfer operation;
The obstacle detection area is selected in accordance with a driving situation including an actual traveling speed, a steering direction, and a transfer operation of the vehicle body, and information on the selected obstacle detection area is used as the plurality of first obstacles. With an obstacle detection safety control section to send to the object detection device,
The obstacle detection safety control unit is
A forklift type automatic guided vehicle that performs control for stopping the vehicle body when the first obstacle detection device detects that there is an obstacle in the selected obstacle detection area. In the forklift type automatic guided vehicle according to claim 1,
A second obstacle detection device for detecting an obstacle in the traveling direction of the vehicle body;
A guidance control device for controlling unmanned travel of the vehicle body,
The guidance control device includes:
Based on the position of the obstacle detected by the second obstacle detection device, a deceleration control region for performing deceleration control of the vehicle body and a stop control region for performing control for stopping the vehicle body are set, and A forklift-type automated guided vehicle that controls to decelerate or stop traveling. In the forklift type automatic guided vehicle according to claim 1,
The driving situation includes at least one of the presence or absence of a load, the shape or size of the load, and whether or not the load is deformed. In the forklift type automatic guided vehicle according to claim 1,
The first obstacle detection device includes:
The forklift type automatic guided vehicle is arranged at a rear lower part and left and right front lower parts, and has a height of 100 mm to 250 mm on a running surface of the vehicle body. A guidance control device for controlling unmanned traveling of the vehicle body;
A first obstacle detection device for detecting obstacles around the vehicle body;
Obstacle detection safety that determines whether or not the obstacle exists in the set area, combines the determined signal and the signal of the guidance control device, and performs stop control of the vehicle body according to the driving state of the vehicle body A forklift type automatic guided vehicle comprising a control unit. In the forklift type automatic guided vehicle according to claim 5,
A second obstacle detection device for detecting an obstacle in the traveling direction of the vehicle body;
A guidance control device for controlling unmanned travel of the vehicle body,
The guidance control device includes:
Based on the position of the obstacle detected by the second obstacle detection device, a deceleration control region for performing deceleration control of the vehicle body and a stop control region for performing control for stopping the vehicle body are set, and A forklift-type automated guided vehicle that controls to decelerate or stop traveling. A detection area storage unit in which an obstacle detection area around the vehicle body set in accordance with a driving situation including a traveling speed of the vehicle body, a steering direction, and a transfer operation is stored in advance;
A plurality of obstacle detection areas are selected in accordance with driving conditions including actual traveling speed, steering direction, and transfer operation, and information on the selected obstacle detection areas is used to detect the surrounding environment of the vehicle body. An obstacle detection safety control unit to be sent to the first obstacle detection device,
The obstacle detection safety control unit performs control to stop traveling of the vehicle body when the first obstacle detection device detects that there is an obstacle in the selected obstacle detection area. Control device. The control device according to claim 7,
The operation state includes at least one of the presence or absence of a load, the shape or size of the load, and whether or not the load is deformed. The control device according to claim 7,
The first obstacle detection device includes:
The control device, wherein the control device is disposed in a rear lower portion and left and right front lower portions, and has a height of 100 mm to 250 mm on a running surface of the vehicle body. Whether or not there is an obstacle in the set area is determined by a detection signal of the first obstacle detection device, and the determined signal and a signal of a guidance control device for controlling unmanned traveling of the vehicle body A control apparatus that performs stop control of the vehicle body according to a combination and an operating state of the vehicle body. A control method for a forklift type automatic guided vehicle including a first obstacle detection device, a detection area storage unit, and an obstacle detection safety control unit,
In the detection area storage unit, an obstacle detection area around the vehicle body that is set according to the driving situation including the traveling speed of the vehicle body, the steering direction, and the transfer operation is stored in advance.
The obstacle detection safety control unit selects the obstacle detection region according to a driving situation including an actual traveling speed, a steering direction, and a transfer operation of the vehicle body, and selects the obstacle detection region of the selected obstacle detection region. Sending information to the plurality of first obstacle detection devices;
The first obstacle detection device detects that there is an obstacle in the obstacle detection area;
The obstacle detection safety control unit controls the forklift type automatic guided vehicle to stop traveling of the vehicle body when it is detected that there is an obstacle in the selected obstacle detection area. Method. In the control method of the forklift type automatic guided vehicle according to claim 11,
The forklift type automatic guided vehicle includes a second obstacle detection device and a guidance control device that controls unmanned traveling of the vehicle body,
The second obstacle detection device detects an obstacle in the traveling direction of the vehicle body,
The guidance control device includes a deceleration control region for performing control for decelerating the vehicle body and a stop control region for performing control for stopping the vehicle body according to the position of the obstacle detected by the second obstacle detection device. A control method for a forklift type automatic guided vehicle, characterized in that the control is performed to decelerate or stop the travel of the vehicle body. In the control method of the forklift type automatic guided vehicle according to claim 11,
The driving situation includes at least one of the presence or absence of a load, the shape or size of the load, and whether or not the load is deformed. Control method. In the control method of the forklift type automatic guided vehicle according to claim 11,
The first obstacle detection device includes:
A control method for a forklift type automatic guided vehicle, characterized in that the forklift type automatic guided vehicle is disposed at a rear lower part and left and right front lower parts, and has a height of 100 mm to 250 mm on a running surface of the vehicle body. In the control method of the forklift type automatic guided vehicle including the guidance control device, the first obstacle detection device, and the obstacle detection safety control unit,
The guidance control device controls unmanned travel of the vehicle body,
The first obstacle detection device detects an obstacle by scanning around the vehicle body,
The obstacle detection safety control unit determines whether or not the obstacle exists in a set region, combines the determined signal and the signal of the guidance control device, and determines the vehicle body according to the driving state of the vehicle body. A control method for a forklift type automatic guided vehicle, characterized in that stop control is performed.

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