Robot guide dog adjusts handle stiffness based on slope preferences
Understanding User Preferences of a Slope-Aware Variable-Admittance Filter for a Robot Guide Dog
Robotics
Summary
Helping people guide a robot dog physically can be tricky, especially on hills. The paper looks at how changing how hard or soft the robot’s handle feels can make walking easier. The researchers found that making the handle stiffer going uphill and softer going downhill helps people feel better and perform better. They tested this idea in computer simulations and with sighted people wearing blindfolds to mimic blindness.
What this means in practice
- •For robotic system designers: Design handle control in guide robots that adapt stiffness by slope for better user comfort during physical guidance.
- •For rehabilitation therapy teams: Improve training robots with variable impedance control adapted to terrain slope to assist patients with mobility difficulties.
Authors
Federico Esposito, Mario Selvaggio, Aaron Link, Fabio Ruggiero
Abstract
This letter investigates how the parameters of a slope-aware variable-admittance filter influence user preferences in force-based interaction with a robotic guide dog for visually impaired individuals. The proposed system consists of a quadruped robot equipped with a sensor-free rigid handle for physical guidance. The framework combines path following, momentum-based interaction-wrench estimation, and a variable-admittance filter whose stiffness and damping are adapted online from slope information extracted by the robot's depth camera. The adaptation policies are evaluated through high-fidelity simulations and a human-subject study involving blindfolded sighted participants. Multiple strategies are compared using a Taguchi L9 design of experiments. Preliminary main-effect results suggest that increasing stiffness uphill and decreasing it downhill improves both objective and subjective metrics, whereas damping shows no significant main effect.