An experimental setup and data acquisition protocol to evaluate the motor performance during a ball-throwing task executed at various gravity conditions visually simulated

Exposure to altered gravity disrupts visual-motor coordination by perturbing internal models based on prior expectations. The cerebellum’s role in sensory-motor integration under different gravitational environments remains unclear. To better understand it, it may be useful to design a setup, allowing for the analysis of the joint kinematics and dynamics during the execution of a common task in variable simulated gravity, that is compatible with the application of cerebellum stimulation techniques. This preliminary study assesses the feasibility of a setup combining a Mixed Reality environment, stereophotogrammetry, and musculoskeletal modeling to evaluate upper limb kinematics and dynamics in visually simulated altered gravity. Four healthy participants performed 20 ball-throwing trials each, under five randomized gravity conditions (hypergravity, Earth, Mars, Moon, microgravity). Results showed no clear adaptation in joint range of motion or net joint moments, indicating the absence of motor learning within the session. Thus, this protocol is functional for future studies exploring the effects of cerebellar non-invasive stimulation on upper limb coordination in visually altered gravity conditions.