Use of sensor technology for prosthetic developments
We are witnessing the beginning of a new era in the design and functionality of prosthesesAdvances such as 3D printing, AI-driven prosthetics, and advanced neural interfaces are transforming the possibilities for amputees. These innovations enable the creation of highly customized devices that fit better, provide greater comfort, and enable an intuitive user experience.
The sensor technology supports many medical equipment and improvements in healthcare. Interface sensors are used in the development, design, and testing of modern prostheses resulting in a more natural and intuitive user experience. By accurately measuring weight, forces, and torque, these sensors provide critical real-time feedback.
An important aspect of these advances is the accuracy of data from measurement sensors. These sensors can be used in product development and invention, allowing for customized customization. For example, miniature load cells in a test for a prosthetic hand can detect the magnitude of the applied force, preventing objects from slipping or being crushed.
The integration of small sensors, such as load button load cells or our SuperSCA quarter-sized prosthetic limb can help test how prosthetic limbs can dynamically adapt to the user's movements and environmental conditions. Load cells used in prosthetic limbs can measure resistance and flexibility during transitions from smooth surfaces to uneven terrain, helping to ensure stability and reduce user effort.
A medical research company from Interface wanted to find out how a prosthetic foot reacts when it is loaded in different positions. 3-axis load cell 3A120 from Interface was installed between the leg socket and the prosthetic foot. The 3A120 was then connected to the multi-channel bridge amplifier BSC4D and the PC interface module were connected. Data was recorded for the X, Y, and Z axes. The customer was able to review the results and identify premature flat spots and dead spots during use of the foot. They can now make improvements to the design.
Another important advance is the support provided by sensor-assisted prosthetics for therapists in refining patient movements and optimizing rehabilitation plans. Furthermore, device improvements are supported and remote progress monitoring is enabled, promoting personalized and adaptable therapy. Wireless data acquisition systems streamline testing setups and enable real-time monitoring during rehabilitation.
Specific applications of testing and measurement in prosthetics
Precise force and torque measurements are essential at every stage of a prosthetic's life cycle, from initial research and development to daily use. Here are some application examples.
Controlling grip force using miniature load cells integrated into the prosthetic hands allows precise control of grip force, allowing users to handle delicate objects without damage and firmly grasp heavier objects.
Gait analysis and optimization benefits from load cells and multi-axis sensors embedded in prosthetic feet and ankles. They provide critical data for analyzing gait patterns, identifying imbalances, and optimizing gait for smoother, more energy-efficient movement. This is especially important for adaptive limb modifications.
Improving balance and stability is more accurate when sensors throughout the prosthesis help maintain balance and stability, especially on uneven surfaces or during dynamic activities.
Tactile feedback for object manipulation requires advanced sensory feedback systems, often including ultra-miniature force sensors, that allow the user to “feel” the texture, shape, and weight of objects, greatly improving dexterity and manipulation capabilities.
Materials testing requires high-precision load cells to evaluate the strength, durability, and fatigue life of new prosthetic materials, including advanced composites and 3D-printed components.
Validation of the individual prosthesis design requires accurate force and torque measurements to check the performance and fit of the custom-made prostheses to ensure they meet the specific needs of the patient.
Biomechanics researchers use precision force sensors as indispensable tools for analyzing human movement and the interaction between the body and prosthetics, leading to more natural and efficient designs. Torque transducers help measure rotational forces, which are essential for optimizing the smooth and natural movement of robotic prosthetic joints.
Predictive maintenance of prosthetic components benefits from the use of load cells for monitoring as they can detect subtle changes in component performance or loading, enabling predictive maintenance and extending the life of the prosthesis.
Prostheses must be tested for extreme loads that can occur during falls, accidents, and athletic movements. Fatigue testing of prosthetic components determines the expected service life of these components under normal conditions of use. In a static load test, a SSMF load cell type S with fatigue properties, attached to hydraulic actuators, to apply and measure cyclic loads. During static testing, loads are applied to the specimen, using the load cell signal as force feedback control of the testing machine. In fatigue testing, the force is repeatedly cycled on and off by the actuator to simulate activities such as walking. Tilt tables can be used to apply forces at different angles, simulating the heel-toe motion of walking or running.
Products for prosthetic innovations
Interface specializes in high-precision force measurement solutions, making our products particularly well-suited for integration into advanced prosthetic systems. Our robust and reliable sensors are ideally suited to meet the stringent requirements for diverse measurement capacities, accuracy, durability, and compact size in prosthetic applications.
A medical device manufacturer was developing a new design for an artificial hip joint and needed to verify the load consistency and durability of its design. 6-axis standard load cell of the 6A40B series from Interface was mounted on the manufacturer's test machine, where loads were applied to simulate actual use. Our BX8-AS BlueDAQ series data acquisition system was connected to the sensor to collect data for analysis that will help make design changes and improve the durability of the artificial hip joint.
Products commonly used in the development, testing, and use of prostheses include:
- Mini load cells:
- load button load cells
- S-type load cells
- LowProfile load cells
- Multi-axis load cells
- Torque transducer
- Wireless telemetry systems
- Measuring instruments and amplifiers
- Data acquisition systems
Interface excels at providing products that support the continuous growth, evolution, and customization of the prosthetic medical sector. The broad spectrum of applications in prosthetic research and development, testing, and feedback is ideally suited to Interface's highly accurate and reliable force and torque measurement solutions, helping to create a future where prosthetic limbs offer unparalleled functionality, comfort, and a truly natural feel. Contact our team for more information on your design and testing needs.