Articulated Leg Mobility Vehicle Obstacle Negotiation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional mobility aid vehicles, such as wheelchairs, are unable to effectively navigate high obstacles and maintain stability due to limitations in their mechanical structure and obstacle clearance capabilities.

Innovation Solution

A mobility aid vehicle with a mechanical structure featuring four articulated legs, each with motorized joints controlled independently by actuators, allowing for real-time adjustment of leg positions to maintain stability and overcome obstacles, equipped with a three-dimensional vision system for obstacle detection and a method to calculate and maintain the center of gravity within a support polygon.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Length of moving object

If conventional mechanical structures are used in mobility aid vehicles, then the vehicle structure is simple and easy to manufacture, but the vehicle cannot overcome high obstacles

Engineering Contradiction:
Improveobstacle clearance capabilityVSAvoidmechanical structure complexity
Core Design Contradiction:
Length of moving objectVSDevice complexity

Solution Approach 1:

The vehicle body is divided into multiple articulated segments connected by motorized joints, allowing each segment to be independently controlled to navigate over obstacles while maintaining overall structural simplicity

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The mechanical structure transitions from a static conventional design to a dynamic articulated system with motorized joints that can adjust leg positions in real-time, enabling the vehicle to adapt its shape and configuration to overcome various obstacle heights

Inventive Principle:
Principle #15Dynamics

2Length of moving object

If legs are lifted to overcome obstacles, then obstacle crossing capability is improved, but vehicle stability deteriorates

Engineering Contradiction:
Improveobstacle clearance capabilityVSAvoidvehicle stability
Core Design Contradiction:
Length of moving objectVSStability of the object's composition

Solution Approach 1:

The control system continuously monitors vehicle stability and leg positions, using sensor feedback to adjust motorized joint actuation in real-time, ensuring that legs are lifted only when stability conditions are satisfied and making corrective adjustments during obstacle crossing

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The control system calculates and prepares the center of gravity position before leg lifting begins, pre-positioning the vehicle to ensure stability is maintained throughout the obstacle crossing process

Inventive Principle:
Principle #10Preliminary action

3Adaptability or versatility

If motorized joints are added to each leg for independent control, then adaptability to obstacles is improved, but device complexity increases

Engineering Contradiction:
Improveobstacle adaptation capabilityVSAvoidcontrol system complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The motorized joints and control system are designed to perform multiple functions: obstacle crossing, stability maintenance, and terrain adaptation, allowing a single complex mechanism to handle various operational requirements without requiring separate specialized systems

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentEP3522845B1Mobility assistance vehicle adapted to negotiate obstacles
Publication Date: 2020.11.04 CAZALI CHRISTOPHE
  • EP3522845B1 patent drawingFigure 1
  • EP3522845B1 patent drawingFigure 2~3
  • EP3522845B1 patent drawingFigure 4~5

AI summary

The invention mainly concerns a mobility assistance vehicle (1) designed to negotiate obstacles (33, 35) while keeping the attitude of same horizontal, comprising a mechanical structure (2) supporting at least one seat (3), control means (19), at least four articulated legs (6a, 6b, 6c, 6d) and equipped with motorised wheels, characterised in that: i. each first segment (7a-7d) is mounted on one of the lateral sides (200) of the mechanical structure (2) by a motorised articulation (10a, 10b, 10c, 10d), each opposing lateral side (200) being linked to at least two legs (6a-6d), and in that, ii. the control means (19) are capable of controlling the motorised articulations (9a - 9d, 10 -10d) of the legs (6a - 6d) separately from each other, in particular when said legs (6a - 6d) are raised successively in order to negotiate an obstacle (33, 35) in a permanently stable situation.