Robotic Programming and Software Development
117601VAL-I
Q9(a). Explain the structure and classification of VAL Language Commands. Write examples of Hand control and Program control commands in VAL-I.20257m
VAL-I
View this question on its own page →Explain the structure and classification of VAL Language Commands. Write examples of Hand control and Program control commands in VAL-I.
Worked SolutionSolution: VAL Language Commands
Introduction
VAL (Variable Assembly Language) is a robot programming language used with industrial robot systems. VAL/VAL-II commands can be grouped according to their purpose, including motion, hand/end-effector control and program control.
Classification of VAL Commands
1. Motion Control Commands
Used to move the robot to taught or specified positions.
Examples include commands conceptually equivalent to:
MOVE P1 MOVE P22. Hand Control Commands
Used to operate the robot's end effector or gripper.
Examples:
OPENI CLOSEIThe exact instruction names can vary with the VAL controller/version; the important purpose is to open/close or actuate the robot hand.
3. Program Control Commands
Control the sequence of execution, including calls, branches, waits and program termination.
Examples conceptually include:
CALL PICK WAIT STOP4. I/O and Sensor Commands
Used to read inputs and control outputs associated with sensors, grippers and external equipment.
5. Variable/Data Commands
Used to store and manipulate positions, numerical values and status information.
Example Pick-and-Place Sequence
MOVE PICK_APPROACH MOVE PICK CLOSEI MOVE PICK_APPROACH MOVE PLACE OPENI MOVE HOMEHand Control
Hand commands directly control the end effector. For example, an open-hand command releases a workpiece, while a close-hand command grips it.
Program Control
Program-control commands determine execution flow. For example, a call command can execute a subprogram, a wait command can synchronize operation with a sensor, and a stop/end command can terminate execution.
Conclusion
VAL commands are organized according to functions such as motion, hand control, program control, I/O and data handling. This classification makes industrial robot programs easier to structure and maintain.