Upper Body Gesture Control for Powered Lower Extremity Orthotics

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Powered lower extremity orthotics, such as exoskeletons, require a means to interpret user intentions for leg movement, especially for paraplegic patients who are completely paralyzed, to enable walking and other mobility tasks, as existing systems lack effective human-machine interfaces to translate upper body gestures or signals into leg actions.

Innovation Solution

A system and method that uses sensors to monitor upper body arm movements, walking aid positions, and velocities to determine desired leg movements, integrating this information into a finite state machine that controls the sequential operation of powered lower extremity orthotic components, allowing users to convey intent through gestures and signals, thereby regulating the exoskeleton's actions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If sensors monitor upper body arm movements and walking aid positions to determine desired leg movements, then the ability to enable walking and mobility tasks for paraplegic patients is improved, but the device complexity increases

Engineering Contradiction:
Improveability to enable walking and mobility tasksVSAvoiddevice complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The control system is segmented into multiple independent components: arm movement sensors, walking aid position sensors, finite state machine controller, and powered orthotic actuators. Each component performs a specific function, and they are integrated through a modular architecture that processes inputs separately before coordinated output, reducing overall system complexity while maintaining versatility

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

A finite state machine serves as an intermediary between the sensors (monitoring arm movements and walking aid positions) and the powered orthotic actuators. This intermediary layer translates complex sensor inputs into discrete, manageable control states that drive leg movements, simplifying the control architecture while enabling sophisticated mobility tasks

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If a finite state machine controls sequential operation of powered lower extremity orthotic components, then safety and determinism in state transitions are improved, but the ease of operation decreases

Engineering Contradiction:
Improvesafety and determinism in state transitionsVSAvoidease of operation
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The finite state machine implements dynamic state transitions that adapt to real-time sensor inputs from arm movements and walking aid positions. The system transitions between predefined safe states based on detected user intentions, maintaining deterministic behavior while responding dynamically to changing conditions, thus preserving reliability without requiring complex manual intervention

Inventive Principle:
Principle #15Dynamics

3Ease of operation

If the system interprets user intentions through upper body gestures and signals, then the ease of operation is improved for paraplegic users, but the measurement precision requirements increase

Engineering Contradiction:
Improveease of operationVSAvoidmeasurement precision
Core Design Contradiction:
Ease of operationVSMeasurement precision

Solution Approach 1:

The system merges data from multiple sensor sources (arm movement sensors and walking aid position sensors) to interpret user intentions. By combining these measurement streams, the system achieves robust intention recognition that compensates for individual sensor precision limitations, maintaining ease of operation while managing measurement precision requirements through sensor fusion

Inventive Principle:
Principle #5Merging (Combining)

Data Source

PatentUS11096854B2Human machine interfaces for lower extremity orthotics
Publication Date: 2021.08.24 EKSO BIONICS INC
  • US11096854B2 patent drawing
  • US11096854B2 patent drawing
  • US11096854B2 patent drawing

AI summary

A system and method by which movements desired by a user of a lower extremity orthotic is determined and a control system automatically regulates the sequential operation of powered lower extremity orthotic components to enable the user, having mobility disorders, to walk, as well as perform other common mobility tasks which involve leg movements, perhaps with the use of a gait aid.