Which statement correctly differentiates point-to-point motion from continuous path motion?

• A. Point-to-point moves between joint configurations with no path constraint; continuous path defines a smooth end effector path in Cartesian space.
• B. Point-to-point plans a Cartesian path; continuous path moves separate joints.
• C. Point-to-point uses impedance control; continuous path uses torque control.
• D. Point-to-point is only for fixed-base robots; continuous path is for mobile robots.

Answer: (A)

Point-to-point motion specifies only the endpoints in joint space and does not impose a specific path in the workspace. The robot moves from one set of joint angles to another, and the actual route through the intermediate joint configurations is not constrained to follow any particular end-effector trajectory, which can lead to varied or abrupt Cartesian paths depending on the arm’s configuration.

Continuous path motion, on the other hand, defines a smooth trajectory for the end effector in Cartesian space. The task is to have the tool follow a prescribed path (a line, curve, or set of waypoints) while the joints cooperate to trace that path, with timing and velocity/acceleration profiles ensuring smooth motion.

This distinction matters in practice: point-to-point is simple and focuses on getting between configurations, while continuous path is essential when the exact surface or line to be traced must be followed precisely.

The other statements don’t describe this fundamental difference—one centers on a specific joint-space endpoint-to-endpoint move, the other on a continuous task-space path—so they don’t capture how endpoints versus paths are defined in motion planning.