JPS63284607A - Push-pull control system for mobile robot - Google Patents

Abstract

PURPOSE:To avoid the damage, etc., of an object to be carried by adding a working process after a preparatory process and realizing the fine control of a mobile robot. CONSTITUTION:A push-pull P-P control system for a mobile robot 1 consists of a P-P device 2, a mobile robot drive controller 3, a vehicle traffic controller 4, and a hand controller unit 5. In an automatic operation mode, the commands are delivered from the controller 4 as the command cues for the moving speed, the moving distance and the weight of an object to be carried. The P-P preparatory processes includes the transmission of the arrival signal to the load receiving platform of the robot 1, a waiting state of a minute time, the error processing and the discontinuation of transmission of said arrival signal. Then a P-P working process is started including the selection of contacts, the selection of modes, the execution of the P-P control, the limit interruption, a waiting state of a prescribed time, etc. Thus the fine drive control is given to the fork and the hook of the device 2.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a push-pull (pp) control system for a traveling robot used, for example, as an automatic guided vehicle.

[Conventional technology]

The punch-pull system is often used for moving and loading objects to be transported in automatic guided vehicles. A traveling robot as an automated guided vehicle can be driven in automatic mode or manual mode.

In automatic mode, commands such as speed, distance, and loaded weight are sent to the vehicle controller (VTC).
After confirming the direction of the conveyance vehicle and the push-pull state, if it is possible to travel, the vehicle is controlled to move, and when it reaches the stop position, the stop position is controlled and the vehicle is moved to a predetermined position. Stop at. Thereafter, the push-pull device is driven and controlled to transfer and receive the loaded items. In the case of manual control, only the speed command is given as a command queue. The push-pull device is equipped with a hook and a fork, and these are properly controlled by adjusting the timing with the robot's travel control to perform the desired movement without causing the object to fall or collide. Can be carried out.

[Problem that the invention seeks to solve]

In the push-pull control of a traveling robot as described above, fine control is required for the operation of the hook that fixes the transported object in conjunction with the traveling control of the traveling robot, and the operation of the fork that receives and transfers the transported object. Conventional methods were not always satisfactory.

An object of the present invention is to introduce an operation step following the preparation step in the control of a push-pull device, perform fine control, smoothly control the operation of the push-pull device, and prevent damage to the objects to be transported. It is to make it.

[Means for solving problems]

In the present invention, in the control method of a push-pull device for loading and unloading objects to be transported by a traveling robot, following the preparation step, the following steps of performing a push-pull operation are provided. includes the following steps:

The process of selecting the contacts to release the brakes of the fork and hook of the push-pull device. When the specified mode is automatic, the process of investigating the current position of the fork and hook. The process of performing push-pull operation. The process of continuing push-pull operation until it reaches a pre-set limit value, and proceeding to the next process when the limit value is reached; The process of rotating the motor that drives the push-pull device in the forward or reverse direction; The process of rotating the motor that drives the push-pull device in the forward or reverse direction A process that determines whether the fork has returned to its original position, generates an alarm if it does not return, and proceeds to complete the process if it returns.If the specified mode is manual, it waits for a certain period of time (for example, 100 milliseconds). process, the process of reading the state of the fork, the process of reading the analog value input from the joystick that manually controls the travel of the traveling robot and the push-pull device, and the process of determining whether to drive the push-pull device to the right or left. , a process of branching to each process, and a process of turning off the motor in response to an interrupt signal from a limit switch in each drive direction after driving the push-pull device.

[Effect]

The push-pull operation steps described above allow fine drive control of the forks and hooks of the push-pull device in both automatic and manual modes.

〔Example〕

A flowchart of each step of the push-pull control method for a traveling robot as an embodiment of the present invention is shown in FIG. 3, and details of the P-P operation step in FIG. 3 are shown in FIGS. 1 and 2. Further, a schematic diagram of a system implementing the method of FIG. 3 is shown in FIG. 4.

In FIG. 3, first, in the case of automatic mode, commands for speed, travel distance, and weight of the object to be transported are given from the travel control device, and these are output as a command queue (Step Sl).
. Next, check whether the direction of the robot and the state of the P-P device are normal (Step S2), and form a transfer command in the buffer (for example, whether the next transfer target should be transferred on the left or the right side, etc.) ) (Step S3). The object to be transported is moved to the position of the loading platform to be transported (step S4), and the encoder (E
Stop by an interrupt signal from NC) (Step S5)
.

The encoder is connected to the wheels of the traveling robot and can detect the distance traveled. When using manual mote, a speed command from the hand controller unit (IcIJ) is given as a command queue.

The P-P$ preparation step (S6) includes the following steps.

When the traveling robot arrives at the receiving platform, an arrival signal (DO27
), a step of waiting for a very short time, for example, about 50 milliseconds, and if either D117 or 24 is input, the robot's running direction is checked against the command to the fork of the P-P device. to determine whether the relationship is correct, and if the relationship is not correct, an error process is performed, and if the signal of D117 or DI24 does not enter after a certain period of time, an alarm is output, and the above verification confirms that the relationship is correct. If so, the process of stopping the light emission of D027.

Here, D117 is the left release (RLS) signal to the sensor of the PP device and DI24 is the right release signal. DO means digital output, and DI means digital input.

Next, the process proceeds to PP operation step S7. This process is shown in detail in FIGS. 1 and 2. The P-P operation process includes the following steps.

Contact selection step (S71): This step is a step in which one of the DI/DO signals is selected and operated.

As shown in Figure 5, when operating the fork, D
When O21 controls the left hook, 0022 is selected, and when O21 controls the right hook, D023 is selected. Details of the Dr/Do signal are explained in FIG.

Mode selection step (S72): In this step, automatic mode or manual mode is selected. The automatic mode is controlled from the travel control device 4 side, and the manual mode is controlled using the HCIJ5.

Fork/hook (FK/H'K) current position investigation process (
S73): In this step, the current position of the fork or hook is checked. A fork is a device that protrudes to the left or right to pass a loaded object to the left or right, pick it up from the left or right, and then return it. Hooks are used to prevent loaded objects from falling, and can be extended or retracted.

P-P execution step (S74): A step in which push-pull driving is performed, and the fork and hook operate according to the command.

Limit interrupt step (S75): When the fork or hook operates and reaches its operating limit, a limit switch or the like operates, and a limit interrupt is performed by the signal (D I 25/26).

Forward/reverse process after reaching the limit (S76): This is a process in which the fork that reached the limit in the previous process is returned to its original position by rotating the motor in the opposite direction.

Determination Step (S77) If it is determined in the previous step that the object has returned to its original position, the process proceeds to the next step, and if it has not returned, an alarm is generated.

On/off switch (SW) switching process (37B):
A signal displayed on the operation panel of the joystick (JS) indicates a return to the origin.

It is determined whether the above process is completed (step 579), and if it is not completed, the process returns to step S77, and if it is completed, the process ends.

In the manual mode, the process branches from step S72 and waits for a predetermined time (S8): for example, about 100 milliseconds.

FK status reading step (S82): Detected by DI25 and DI26.

JS analog value reading step (S83): This is a step of reading an analog command signal input from the joystick.

Determining whether or not the fork is moving to the right (S84): If the fork movement is in the right direction, proceed to step S87; if it is in the other direction, proceed to step S
Proceed to 85.

Determining step (385) whether the fork is moving to the left: If the movement of the fork is to the left, proceed to step 388; if it is in the other direction, proceed to step 3.
Proceed to 86.

FK motor off step (S86): The drive of the fork drive motor is stopped to complete the entire process.

Steps S87 and 38B are indicated in the figure and are shown in FIG. 2 as a joystick motion loop. Although steps S87 and S8'8 are the same step, their detailed divided steps are referred to as 5871-5879 and 5881-5889, respectively. The former will be explained here.

JS reading step (S871): This is a step of reading commands from the joystick.

Right side rimiso) (LM) Interrupt process (S872): Four
If the right side LM is driven to the right and turns on the limit switch, and a signal is output to cause an interrupt, the process proceeds to step 5873, and if there is no right LM interrupt, the process proceeds to step 5874.

Left side limit) (LM) Interrupt step (S874): When the fork is driven to the left and the limit switch is turned on, a signal is output and an interrupt is performed, the process advances to step 5875, and when there is no left LS interrupt, Proceed to step 5876.

FK center interrupt step (S876): When the fork is in the center position, the switch contact is turned on and an interrupt signal is output, proceeding to step 5877; otherwise, proceeding to step 8878
Proceed to.

Step of determining whether JS is in the center (S878): If the joystick is in the center position, the process advances to step 5879; if it is not in the center position, the process returns to step 871.

Steps 3873.5875.5877, and 5879
In both cases, the motor is turned off, the contacts are turned off, and the process returns.

After the above P-P operation step (S7) is completed, the following steps are further performed.

That is, after the limit interrupt step (S8), an on-off inch switching step (S9) is performed, and then a deceleration step (SIO) of the P-P device is performed to stop it at a predetermined position (
Step 511). After stopping, it is determined whether the push-pull operation is completed (step 512), and if it is completed, all the steps are ended, and if not, the motor direction switching step (313) is performed and the process returns to before step SIO and is repeated.

FIG. 6 shows a PP operation flowchart. In the figure, the transmission and reception of control signals between the traveling robot, the motor of the P-P device, the brake, the proximity switch, and the ICU will be explained.

FIG. 7 shows details of input/output signals to the PP device.

〔Effect of the invention〕

According to the present invention, the push-pull device of the traveling robot can be precisely controlled, the operation of the push-pull device can be smoothly controlled, and damage to the object to be transported can be prevented.

[Brief explanation of the drawing]

Fig. 1 is a flowchart of the P-P operation process of an embodiment of the present invention, Fig. 2 is a partial flowchart showing a part of the process of Fig. 1, and Fig. 3 is a control of an embodiment of the present invention. Figure 4 is a schematic block diagram of the system of the embodiment shown in Figure 3, Figure 5 is a diagram explaining contact selection in the process shown in Figure 1, and Figure 6 is the operation of the process in Figure 1. The flowchart and FIG. 7 are diagrams explaining input/output signals to the PP device. In the figure, 1... Traveling robot, 2... P-P device, 3... Traveling robot drive control device, 4... Traveling control device, 5... Hand controller unit (l (CU)). Traveling robot 2 Traveling 4 P'-P i position Control device] Traveling robot 3 Process flow chart of the control method of the embodiment of the drive control device 3yJ Block diagram of the traveling robot stem Figure 4 Do double signal of contact selection 5 Figure P-P operation Flowchart Fig. 6 Input/output signals to P-P device Fig. 7

Claims (1)

[Claims] In a control system for a push-pull device for loading and unloading objects to be transported by a traveling robot, following the preparation step, the following steps for performing a push-pull operation are performed, namely, the forks of the push-pull device and A step of selecting a contact point to release the brake of the hook. When the specified mode is automatic, a step of investigating the current position of the fork and the hook. A step of performing a push-pull operation. a step of continuing the push-pull operation until a limit value is reached, and proceeding to the next step when the limit value is reached; a step of rotating a motor that drives the push-pull device in a forward or reverse direction; a step in which the fork of the push-pull device Determine whether it has returned to its original position, generate an alarm if it does not return, and proceed to complete the process if it returns; If the specified mode is manual, wait a certain period of time; Read the state of the fork. a step of reading an analog value input from a joystick that manually controls the travel of the traveling robot and the push-pull device; determining whether to drive the push-pull device to the right or to the left, and performing each step; and, after driving the push-pull device, turning off the motor in response to an interrupt signal from a limit switch in each driving direction. .