Haptic Human-Robot Collaboration for Walker-Assisted Navigation Based on Admittance Controllers

In recent years, advances in robotics and the constant growth of gait-related pathologies led to the development of different assistive devices. Smart walkers provide natural and intuitive strategies for gait assistance, such as path-following and guidance. Although these functionalities usually employ shared control approaches, the users' level of participation has yet to be assessed. This work presents the implementation of three modulation strategies for assisted navigation tasks. A path-following algorithm and a set of admittance-based controllers modulate the control authority between the user and the device. A group of 20 healthy subjects formed the validation group. Results showed a kinematic estimation error of 0.13 m for the strategy that shared the control authority with the user. Statistical tests found significant differences regarding the naturalness of the proposed approach (p-value of 0.00587).