Preshaping Hand Behaviour for Direct and Indirect Manipulation of 3D Objects

Effortless manipulation informs and relies on preshaping: the subconscious posing of the hand before grasping. Virtual environments and the design of interaction techniques alters interaction requirements like contact and reach, forcing behavioural adaptation. We present a comparative study investigating preshaping behaviour across direct versus indirect (gaze-assisted) and bare-hand versus controller techniques on a docking task. Results reveal that response patterns scale with anticipated task difficulty, and that direct techniques elicit effective posing of the hand. Indirect techniques shortcut hand transport and, in turn lacks the sensory feedback to guide planning, inducing efficient but attenuated responses that necessitate compensatory manipulation and clutching. Notably, controllers that afford in-hand rotation allow users to extend their range of motion. These findings can inform interaction design to better afford preshaping and optimise 3D manipulation tasks.