Introduction
At Hodgson Orthopedic Group, we’re always looking to advance healthcare technology. Recently, we teamed up with Simon Fraser University’s (SFU) Engineering Mechatronics department to create a new 3D-printed pressure sensor mat. This mat uses a cool origami-inspired design and promises to change how we monitor and pressure to design the next generation of orthotic and prosthetic devices. Our efforts have been published in Nature Journal’s NPJ for Flexible Electronics!
Methods
Our project aimed to create a flexible, cost-effective pressure sensor mat that overcomes the limitations of current commercial mats. We utilized dual nozzle Fused Deposition Modeling (FDM) 3D printing technology to produce a modular sensor array with a unique pillar-origami structure. This design allows precise control over the sensor’s stiffness and pressure measurement range, ensuring high sensitivity and rapid response times.
The sensor mat consists of two main components: the array and the individual sensing units. The array can be customized in shape and size to meet specific application needs, while the sensing units can be easily replaced if damaged. The pillar-origami structure is key to the sensor’s performance, featuring multifaceted stiffness properties that filter out skin deformations and enable accurate capacitive pressure sensing.
For the materials, we used Thermoplastic Polyurethane (TPU) due to its flexibility and durability. TPU NinjaTek Cheetah (95A) was used for creating the flexible base structural elements, and TPU NinjaTek Eel (90A) was used for printing the flexible dielectric components of the sensor. These materials were chosen for their excellent mechanical properties and compatibility with the FDM 3D printing process.
Results
The 3D-printed pressure mapping mat demonstrated exceptional performance across several parameters. It offers a detection range from 70 to 2500 kPa, with sensitivity ranging from 0.01 kPa^-1 to 0.0002 kPa^-1 and an impressive response time of just 800 milliseconds. The modular design enhances maintenance and customization, allowing for greater flexibility in shaping and enhancing the device’s resolution.
Our tests included mapping pressure distribution on human feet and monitoring impact forces on protective pads during sports activities. The sensor mat successfully detected and plotted pressure concentrations in real-time, proving its effectiveness in various scenarios.
Discussion
The applications of our innovative pressure sensor mat are extensive. In healthcare, it can be used for foot pressure mapping to design ergonomic insoles, which can help patients with biomechanical abnormalities and prevent injuries. For athletes, it can monitor pressure distribution on protective pads, providing valuable data to improve training methods and prevent injuries. The modular nature of the mat means that individual sensors can be replaced if damaged, reducing maintenance costs and extending the device’s lifespan.
The mat’s ability to be customized in shape and size makes it adaptable for different uses, from prosthetics to sports equipment. The combination of 3D printing and origami design offers a unique solution that addresses the limitations of traditional pressure mats, making it a versatile tool in various fields.
Conclusion
The collaboration between Hodgson Orthopedic Group and SFU’s Engineering Mechatronics department has resulted in a significant advancement in pressure sensor technology. Our 3D-printed, origami-inspired pressure mat offers a customizable, cost-effective, and highly sensitive solution for a range of applications in healthcare and sports. This innovative technology sets a new standard in flexible and adaptive pressure sensor technology, and we are proud to be at the forefront of this exciting development
