Rotary and Translatory Frame for Ankle Motion Assistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current motion assistance apparatuses for the elderly and patients with joint problems, as well as those for military purposes, lack effective solutions for providing simultaneous translational and rotational motions to assist ankle movements, particularly in dorsi-flexion and plantar-flexion, while minimizing skin chafing and allowing easy donning and doffing of shoes.
Innovation Solution
A motion assistance apparatus featuring a proximal support for the calf, a distal support for the foot, and a rotary and translatory frame that performs both translational and rotational motions relative to the proximal support, with a power distributor and connecting rod system that allows differential speeds and degrees of freedom for ankle assistance, including a four-bar linkage structure and pressure sensors for controlled motion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a motion assistance apparatus provides simultaneous translational and rotational motions to assist ankle movements, then the effectiveness of dorsi-flexion and plantar-flexion assistance is improved, but the device complexity increases
Solution Approach 1:
The motion assistance apparatus is divided into distinct functional modules: a proximal support for the calf, a distal support for the foot, and a rotary and translatory frame with separate rotational and translational components. This segmentation allows each module to perform its specific function independently, simplifying the overall design while achieving complex ankle movement assistance through coordinated action of simpler parts.
2Measurement precision
If the motion assistance apparatus provides controlled differential speeds for power distribution to achieve natural ankle motion, then the motion control precision is improved, but the device complexity increases
Solution Approach 1:
The power distributor dynamically adjusts the transmission of power to the rotary and translatory frame based on the user's movement phase and intensity. The system provides controlled differential speeds by varying power distribution in real-time, enabling natural ankle motion patterns without requiring overly complex mechanical speed control mechanisms. The dynamic adaptation allows precise motion control while maintaining relative simplicity in the power transmission architecture.
3Reliability
If the rotary and translatory frame is positioned on the anterior of the ankle to assist movement, then the effectiveness of motion assistance is improved, but skin chafing increases
Solution Approach 1:
The distal support is designed with differentiated local qualities: the anterior portion that contacts the foot has smooth, low-friction surfaces to minimize skin chafing, while the structural components maintain the necessary rigidity for effective motion assistance. The frame positioning on the anterior of the ankle is optimized to provide mechanical leverage for dorsi-flexion and plantar-flexion while using locally adapted surface properties to reduce harmful friction effects on the skin.
4Adaptability or versatility
If the motion assistance apparatus uses a four-bar linkage structure with multiple degrees of freedom, then the adaptability to natural ankle motion is improved, but the device complexity increases
Solution Approach 1:
The rotary and translatory frame serves multiple functions simultaneously: it provides rotational motion for dorsi-flexion and plantar-flexion, translational motion to accommodate ankle joint movement, and structural support for the distal attachment. This multi-functionality allows a single mechanism to adapt to various phases and intensities of natural ankle motion without requiring separate specialized components for each function, thereby reducing overall system complexity while maintaining high adaptability.
Data Source
Figure 1A
Figure 1B
Figure 2
AI summary
A motion assistance apparatus comprising: a proximal support configured to support a proximal part of a user; a distal support configured to support a distal part of the user; and a frame structure connected between the proximal support and the distal support, the frame structure configured to provide an assistance force to assist the user with a movement.