Robot basics

Motion is the basic and essential feature of industrial robots. The 2 main things to consider are: where to move & how to get there

Target position

A target position indicates where to move. Target positions are recorded in a robot program and the robot moves to the target positions repeatedly. As position is the primary target for industrial robots to achieve, we can say that the robots perform position control.

For industrial robots, the action to record the target positions is normally called teaching. In UR robots, the target positions are called Waypoint and are taught by using hands in Freedrive mode or jogging from Teach Pendant.

Trajectory

A trajectory defines how to reach the target position. A robot can move linearly or by curve. In general, the robot's trajectory depends on the space which the robot refers to.

In UR robots, the trajectory is specified by Move type on the Teach Pendant. We can say that four Move types are available for UR robots: MoveJ, MoveL, MoveP and MoveC. Descriptions of each move type can be found in the User Manual.

Once the target positions are taught and trajectories are specified in the robot program, the robot can move repeatedly according to the program. For industrial robots, it is crucial to keep reaching the target positions and repetitive tasks are the target positions and repetitive tasks are what the robots can do the best. Therefore, what the robots can do the best. Therefore, repeatability is regarded as one of the most important technical specifications.