Relative Waypoint - Universal Robots E Series Original Instructions Manual

Depending on the movement type (i.e., MoveL, MoveJ, or MoveP), different blend trajectories are
generated.
• Blends in MoveP When blending in MoveP, the position of the blend follows a circle arc at
constant speed. The orientation blends with a smooth interpolation between the two
trajectories. You can blend a MoveJ or a MoveL into a MoveP. In such a case, the robot uses
the circular arc blend of MoveP, and interpolate the speed of the two motions. You cannot
blend a MoveP to a MoveJ or a MoveL. Instead, the last waypoint of the MoveP is regarded
as a stop point with no blend. You cannot perform a blend if the two trajectories are at an
angle close to 180 degrees (reverse direction) because it creates a circular arc with a very
small radius which the robot cannot follow at constant speed. This causes a runtime
exception in the program which can be corrected by adjusting the waypoints to cause a less
sharp angle.
• Blends involving MoveJ MoveJ blends cause a smooth curve in joint space. This goes for
blends from MoveJ to MoveJ, MoveJ to MoveL and MoveL to MoveJ. The blend produces a
smoother and faster trajectory than the movements without a blend (see Figure 15.6).
If velocity and acceleration are used for specifying the velocity profile, the blend stays within
the blend radius during the blend. If using time instead of velocity and acceleration for
specifying the velocity profile of both motions, the blend trajectory follows the trajectory of
the original MoveJ. When both motions are time constrained, using blends does not save
time.
• Blends in MoveL When blending in MoveL, the position of the blend follows a circle arc at
constant speed. The orientation blends with a smooth interpolation between the two
trajectories. The robot may decelerate on the trajectory before following the circular arc to
avoid very high accelerations (e.g., if the angle between the two trajectories are close to 180
degrees).

23.11.3. Relative Waypoint

UR5e 160
23. Program Tab
User Manual