Speed Picker Y Limit

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Speed Picker "Singularity"

At J2 angle of 90 degrees, where Y reaches its maximum, the Speed Picker robot (Traverse Arm kinematics) behaves like in a vicinity of a singular point. Typically this can occur when the motion interpolation is Cartesian mode, which means that the robot is actuated by MOVES or CIRCLE command or the robot is tracking conveyor (slave = 5). In such cases when the robot is close to the point #{X,± L1, Z, R} velocity and acceleration of all joints increase drastically. And the position limit protection mechanism that is fired takes the initial values of velocity and acceleration which are far above their maximal values. This cause the generation of a stopping profile that is too long, i.e. an coasting of the robot occurs.

The issue was resolved in firmware versions 4.5.24 and later, in which values of initial acceleration are limited to Sys.MotMargin*vmax value.

Recommended Limits

It is recommended to limit the workspace of Cartesian motion to L-T×VmaxTran where T is the motion sample period and VmaxTran is the maximum translational velocity robot reaches.

In a real application it means reducing Ymax by about 5 mm.

See Also: Sys.MotionMargin