Controlled direct 3D sketching with haptic and motion constraints

Present work concerns intuitive generation of 3D sketches with intrinsic support for space constraints and articulation for multi-component product conceptualisation. The issues of lack of precision, stability and control in direct creation of 3D strokes in air, arising out of inadequacy of the proprioceptive feedback alone, are mitigated in this work with inclusion of stereoscopic display and haptics. Investigations based on paper-pencil analogy for haptic rendering revealed that pen-tilt-based method is more effective. For spatial conformity, surface and volumetric constraints have been studied using the novel reactive and field-based haptic rendering schemes. Methodologies for automatic perceptual grouping of strokes enabled interactive exploration of motion in articulated 3D concept sketches. Experiments with designers using the proposed 3D sketching system established that modelling of constraints is the central issue in 3D sketching. For more immersive experience, eye-movement coordinated realistic stereo-rendering and advanced interfaces for large-scale design scenarios are being pursued