Improved Haptic Rendering through Suppressing the Position-Sensor Quantization Effects

Rendering rigid virtual objects remains a challenging problem in the field of haptics. The "nonidealities" due to time discretization and position quantization are the main factors that constrain the maximum achievable stiffness for the virtual objects. While the former can be addressed with many methods, the latter becomes a critical problem. New simulation methods, smoothing the output force with a dynamic moving-average filter (MAF) while the velocity is low, and a nonlinear spring model combining the linear spring model with a square-root spring model, are presented to suppress the noisy behavior of position-sensor quantization. The proposed methods are testified experimentally with ldquovirtual wallrdquo prototype system based on Delta haptic device.