Enhancement of a control approach to display high stiffness in virtual environments

Kurzfassung

Haptic feedback is a powerful tool to display virtual environments in a detailed and immersive way. However, stably realizing virtual objects with high stiffnesses remains a difficult task, mainly due to time discretization. The Successive Force Augmentation approach is based on a concept of progressively changing the displayed force in order to achieve a desired stiffness. Primarily based on a low stiffness, the force is successively adapted during the interaction until the desired stiffness is reached. This thesis covers the enhancement of the Successive Force Augmentation approach using alternative methods to update the displayed force to reduce response time, a passivity controller to ensure stability as well as a filter to avoid discontinuities in the displayed force. Furthermore, the enhanced approach is then extended to three translational dimensions. For validation, multiple experiments are conducted to compare different implementations with each other and the relevant haptic control approaches Time-domain Passivity Approach and Force Bounding Approach.