Robotic Walker for Slope Mobility Assistance with Active-Passive Hybrid Actuator

Junqiang Li,Tiejun Li,Lei Zhao

doi:10.1186/s10033-021-00618-8

Junqiang Li, Tiejun Li + Show 1 more

Open Access

https://doi.org/10.1186/s10033-021-00618-8

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Abstract

Walking assistance can be realized by active and passive robotic walkers when their users walk on even roads. However, fast signal processing and real-time control are necessary for active robotic walkers when the users walk on slopes, while assistive forces cannot be provided by passive robotic walkers when the users walk uphill. A robotic walker with an active-passive hybrid actuator (APHA) was developed in this study. The APHA, which consists of a rotary magnetorheological (MR) brake and a DC motor, can provide mobility assistance to users walking both uphill and downhill via the cooperative operation of the MR brake and DC motor. The rotary MR brake was designed with a T-shaped configuration, and the system was optimized to minimize the brake volume. Prototypes of the APHA and robotic walker were constructed. A control algorithm for the robotic walker was developed based on the characteristics of the APHA and the structure of the robotic walker. The mechanical properties of the APHA were characterized, and experiments were conducted to evaluate the mobility assistance supplied by the robotic walker on different roads. The results show that the APHA can meet the requirements of the robotic walker, and suitable assistive forces can be provided by the robotic walker, which has a simple mechanical structure and control method.

Highlights

The rapid growth of the elderly population in today’s society has resulted in an increase in the proportion of elderly people who require assistance in their daily living
When the current was 4.0 A, the passive and active torques were 27.2 N⋅m and 26.8 N⋅m, respectively. These results demonstrate that the performance of the active-passive hybrid actuator (APHA) meets the requirements of the robotic walker
The MR brake used in the APHA was designed based on the torque requirements of the robotic walker

Summary

Introduction

The rapid growth of the elderly population in today’s society has resulted in an increase in the proportion of elderly people who require assistance in their daily living. Safe and independent walking is an important part of improving their quality of life [1, 2]. The ability to walk independently helps to sustain social interactions and is beneficial for both physical and mental health. It is important to provide tools that preserve the walking ability of the elderly. Researchers have developed various walking assistance devices such as canes [3, 4], walkers [5], and exoskeleton robots [6, 7]. A walker is a widely used device for elderly users who need additional support to maintain

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Results

Conclusion