While doing a literature review of mobile robots in general and mobile hexapods in particular I came across a control system defined as "Task level open loop" and "Joint level closed loop" system.
The present prototype robot has no external sensors by which its body state may be estimated. Thus, in our simulations and experiments, we have used joint space closed loop (“proprioceptive”) but task space open loop control strategies.
The relevant paper is A simple and highly mobile hexapod
What is the meaning of the terms "joint-level" and "task-level" in the context of the Rhex hexapod?