Shibaura CA20-M10, Руководство по эксплуатации

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5
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Chapter 5 Multi-task
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5.1 Multitasking
Multitasking refers to executing multiple tasks simultaneously. The multitasking referred to
with this controller refers to executing multiple programs simultaneously. This multiple
execution of programs is asynchronous operation in which the programs do not interfere with
each other.
However, the start of the command execution can be synchronized using commands
dedicated for multitasking, and using counters and timers I/O common between the tasks.

5.2 Merits of multitasking
The explanation will follow the case of creating a system that unloads the part from the
conveyor and places it on the work table.
When the axis is moving to move the part to the work table, the conveyor must be operated to
supply the next part to the unloading position.

When multitasking is not used
In addition to the robot, a programmable logic controller (PLC) for controlling the conveyor
will be required.
Due to this, the system will become complicated as wiring for interlocks, etc., will be
required. This will in turn lead to a larger and more expensive system.
If the conveyor is controlled with the robot I/O instead of using a PLC, the conveyor cannot
be used while the axis is moving, and thus the tact time will increase.

When multitasking is used
The I/O such as the conveyor control and the axis movement can be controlled
simultaneously, so a system can be structured without using a PLC, etc. Thus, the wiring is
simplified and the system is less expensive. Control can be carried out just with the
controller program, so the system development and maintenance are simplified.
作業位置
取り出し位置
ロボット
コントローラ
ベルトコンベアの
コントローラ
ベルトコンベア
ロボット軸
Robot axis
Unloading position
Work position
Belt conveyor
Robot
controller
Belt conveyor
controller