Prosthetic Foot Spherical Pivot Joint for Ankle Motion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current lower limb prosthetic devices are often bulky, unsophisticated, and lack the range of ankle movement, particularly in dorsiflexion, plantarflexion, pronation, and supination directions, which limits user mobility and control.
Innovation Solution
A prosthetic device with a foot portion featuring a semispherical protrusion and a cylindrical rod system that allows for pivotal movement, enabling a wide range of ankle motions through a plate and attachment mechanism, mimicking natural foot movements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If traditional SACH foot device is used, then the device structure is simple and cost-effective, but the ankle motion range is limited with no dorsiflexion and plantarflexion
Solution Approach 1:
The patent employs a spherical protrusion on the foot portion that interfaces with a corresponding spherical recess in the plate portion, creating a spherical pivot joint. This spherical geometry naturally enables multi-axis rotation, providing both dorsiflexion/plantarflexion and pronation/supination motions without requiring complex mechanical linkages or actuators.
Solution Approach 2:
The invention transitions from a static, fixed-ankle structure to a dynamic, movable joint system. The spherical pivot connection allows the foot portion to dynamically adapt its orientation in multiple directions, mimicking natural ankle motion while maintaining a relatively simple overall device structure.
2Adaptability or versatility
If powered smart prosthetic device like BiOM Ankle is used, then the ankle motion control and mobility are improved, but the device weight increases due to actuators
Solution Approach 1:
The spherical pivot joint is a passive mechanical structure that enables multi-axis ankle motion without requiring external power sources, actuators, or complex control systems. The device serves itself through the inherent degrees of freedom provided by the spherical connection, eliminating the need for heavy powered components while maintaining natural-looking ankle movement.
3Adaptability or versatility
If powered prosthetic device with actuators is used, then the range of ankle movement is enhanced, but the device complexity and cost increase significantly
Solution Approach 1:
The spherical protrusion and recess configuration provides a passive mechanical solution that inherently allows motion in multiple planes (dorsiflexion, plantarflexion, pronation, supination) without requiring complex actuated mechanisms. This geometric approach achieves enhanced adaptability while keeping the device structure simple and cost-effective.
4Ease of operation
If fixed at-rest position prosthetic foot is used, then the device structure is simplified, but user mobility and control are limited
Solution Approach 1:
The invention replaces the fixed, static foot structure with a dynamic spherical pivot joint that allows the foot portion to move freely in multiple directions. This dynamic connection significantly improves user mobility and control by enabling natural ankle motions while adding minimal structural complexity through the simple spherical protrusion-recess interface.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The device enhances user control and mobility by allowing significant ankle movement in multiple directions, reducing the risk of tripping and improving walking dynamics, while being potentially lighter and more cost-effective than existing smart prosthetics.
Implementation Method 1
a foot portion (20) having an anterior end and a posterior end and a first surface (33A) having a protrusion (32) that protrudes therefrom adjacent the posterior end of the foot portion, has a semispherical or hemispherical surface, and has a passage therethrough extending laterally relative to the foot portion
Implementation Method 2
A cylindrical rod is located within the lateral passage of the protrusion and has ends protruding therefrom on oppositely-disposed lateral sides of the protrusion. The plate portion is pivotally coupled to the ends of the rod on oppositely-disposed lateral sides of the protrusion.
Data Source
AI summary
Systems and devices for use as lower leg prosthetic devices that include a foot portion having anterior and posterior ends and a first surface having a protrusion that protrudes therefrom adjacent the posterior end of the foot portion, has a semispherical or hemispherical surface with a passage therethrough extending laterally relative to the foot portion. The systems and devices further include a toe portion pivotally coupled to the anterior end of the foot portion, and a plate portion configured to couple to an attachment device and thereby be functionally secured to a user. The plate portion has a recess configured to couple with the protrusion of the foot portion. A cylindrical rod is located within the lateral passage of the protrusion and has ends protruding therefrom on oppositely-disposed of the protrusion. The plate portion is pivotally coupled to the ends of the rod on oppositely-disposed lateral sides of the protrusion.