Blue upper table is kept always horizontal when mowing in 3D horizontal when moving in 3D space.

Motion of the popcorn disk is controlled by two base-mounted of the the popcorn disk is controlled by two two base-mounted motors.

Motion of the blue table along sliding joint on the popcorn disk is controlled by violet actuator.

Disadvantages:

The actuator is not base-mounted.

The calculation of trajectory of a point on the blue table can not be based on spherical coordinate system.