Weight Displacement Seated Mobility Device Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing mobility devices, such as wheelchairs, are not easily operable by users with significant limb impairments and are not suitable for use on various surface types, particularly soft or undulating surfaces, requiring assistance for 'off-road' use and lacking fine control in crowded areas.
Innovation Solution
A powered mobility device with at least two drive wheels, a drive control system, a tilt mechanism allowing seat movement in multiple directions, and a weight displacement sensing system that imparts drive to the wheels based on user weight shifts, enabling hands-free operation and fine control, along with a hand control mechanism for additional steering precision.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If hand controls are used for steering and propulsion, then control precision is improved, but ease of operation deteriorates for users with significant limb impairments
Solution Approach 1:
The patent replaces the mechanical hand control system with a weight displacement sensing system. The sensing means detects the user's body weight shifts on the seat and translates these displacements into steering and propulsion commands, eliminating the need for manual hand controls while maintaining control precision.
Solution Approach 2:
The system enables the user to control the mobility device through their own body movements and weight shifts, allowing the device to serve itself through the user's natural physical actions rather than requiring separate control mechanisms.
2Ease of manufacture
If standard wheelchairs are designed for hard surfaces, then manufacturing simplicity is improved, but adaptability deteriorates for off-road and soft surface use
Solution Approach 1:
The patent incorporates a tilt mechanism that allows the seat to dynamically adjust its angle in response to weight displacement. This dynamic adjustment capability enables the mobility device to adapt to various surface conditions and terrains, improving off-road performance while maintaining a relatively simple base structure.
Solution Approach 2:
The mobility device is designed to perform multiple functions across different environments. The combination of weight displacement sensing, tilt mechanism, and differential wheel control enables the same basic structure to operate effectively on both hard surfaces and soft/off-road terrains.
3Ease of operation
If weight displacement sensing is used for control, then ease of operation is improved for impaired users, but device complexity increases due to additional sensing and control mechanisms
Solution Approach 1:
The patent merges the sensing mechanism with the existing seat structure. The weight displacement sensing means is integrated into the seat assembly, and the tilt mechanism serves dual purposes: providing user comfort/positioning and enabling steering control through weight shift detection, thereby reducing overall system complexity.
4Ease of operation
If the tilt mechanism is made freely movable for steering, then ease of operation is improved, but stability deteriorates when locking is not engaged
Solution Approach 1:
The tilt mechanism transitions between two states: locked and unlocked. When unlocked, it allows free movement for steering operations; when locked, it provides stable positioning. This dynamic state change enables the mechanism to satisfy both ease of operation and stability requirements at different times.
Data Source
AI summary
A mobility device includes at least two drive wheels mounted on a shaft; a drive controller drivingly coupled to the shaft; a seat mounted to a tilt mechanism such that the seat is able to tilt in a forward, backward, left and right directions as a result of the user shifting their body weight in either of those directions; a weight displacement sensor connectable to the tilt mechanism and the drive controller such that upon sensing a weight displacement of a user in a particular direction the weight displacement sensor causes the drive controller to impart drive to the drive wheels to move the mobility device in the direction of the sensed displaced weight of the user so that the mobility device is able to be driven in a forward and backward direction and steered in a left or right direction.