Powered Orthotic System with EMG Sensor and Segmented Actuator
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Individuals with hemiparesis due to stroke or brain injury face difficulty in performing rehabilitation exercises due to severe weakness in affected limbs, requiring assistance to execute functional and familiar tasks effectively.
Innovation Solution
A powered orthotic system with a wearable component featuring a brace with pivot sections, electromyographic sensors, and an electrically powered actuator assembly, controlled by a processor and user interface, which applies forces based on muscle activity to assist in flexion and extension movements, enabling the user to perform rehabilitation tasks with reduced effort.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a powered orthotic system is introduced to assist limb movement, then the user's functional capacity and ability to perform rehabilitation tasks is improved, but the device complexity and cost increase
Solution Approach 1:
The orthotic device is divided into multiple independent sections (first section and second section) that can be separately attached to different limb segments. Each section contains its own actuator assembly, allowing the system to provide targeted assistance at specific joints while maintaining overall system manageability and reducing complexity through modular design.
Solution Approach 2:
Electromyographic sensors serve as intermediaries between the user's residual muscle activity and the actuator assembly. These sensors detect electrical signals from muscles and translate them into controlled mechanical assistance, enabling intuitive control without requiring complex user interfaces or control algorithms.
2Speed
If electromyographic sensors and actuators are integrated into the wearable component, then the system can provide responsive assistive forces, but the weight and bulk of the wearable component increases
Solution Approach 1:
The system replaces complex mechanical control mechanisms with electromyographic sensing and electrical actuation. By using biological electrical signals (EMG) to directly control electric motors, the system achieves rapid responsiveness without requiring bulky mechanical linkages, levers, or complex transmission systems that would increase weight.
Solution Approach 2:
The actuator assembly parameters (torque, speed, force) are dynamically adjusted based on real-time EMG sensor readings. This allows the system to provide precisely the right amount of assistance when needed, reducing the need for oversized actuators that would weigh more, while maintaining high responsiveness to user intent.
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 system enhances the user's functional capacity by providing assistive torques and forces, mimicking natural motion patterns, thereby facilitating motor pattern re-learning and rehabilitation by allowing users to perform tasks that would otherwise be challenging without assistance.
Implementation Method 1
The wearable component includes an electromyographic sensor, an electrically powered actuator assembly in communication with the electromyographic sensor
Data Source
AI summary
A powered orthotic system includes a wearable component having a brace, an EEG sensor, an electrically powered actuator assembly in communication with the EEG sensor, and a controller in communication with the actuator assembly that provides system parameters to control operation of the actuator assembly. The system also includes a control unit in communication with the wearable component. The control unit includes a processor that modifies the system parameters in the controller and a user interface, in communication with the processor, that permits user selection of the system parameters. The control unit includes an auto-calibration mode in which an initial EEG signal level is measured by the EEG sensor for one or more muscles of the user when the muscles are at-rest, and the initial EEG signal level is used to adjust an EEG signal level measured during subsequent operation of the wearable component.