
The FootSens insole prototype.
According to the U.S. Bureau of Labor Statistics, nearly 60% of civilian jobs in 2016 required medium to heavy levels of physical work. In other words, the majority of jobs require physically demanding activities. When these activities are performed repetitively over the course of an individual’s career, they can prove damaging: arthritis, heart disease, stress fractures, and muscle injuries are just a few examples of health complications that may result, with osteoarthritis being the leading cause for physical disabilities among Americans. Wearing proper footwear, finding techniques that minimize bodily stress, and taking adequate breaks can mitigate such effects. Before mitigating approaches can be used, workers and employers need to better understand how daily tasks transmits loads to the body. FootSens is attempting to measure those loads and further reduce the risk of injury due to physically demanding jobs by instantaneously measuring pressure applied to the ball and heel of the foot.
The idea for FootSens started as a collaboration between Professor Grace O’Connell in Mechanical Engineering and Professor Carisa Harris-Adamson in Public Health. Harris’ research focuses on developing wearable technology to assess physical exposure of factory workers. Ongoing work in Harris’ lab uses a vest that can measure the person’s position in space. As part of Professor Grace O’Connell’s Designing for the Human Body course (ME 178 / BioE 137), the FootSens team designed and prototyped a device that would be able to add loads to the collected data. The team consists of UC Berkeley undergraduate students Tiana Johnson Kidd, Radhika Mardikar, Keitaro Murakami, Revati Thatte, and Kristin Yamane. The students have since developed FootSens as an independent research project.

The FootSens sock (top) and insole (bottom).
FootSens is a device that can be worn as a sock or inserted into a shoe as an insole, and pressure is continuously measured through sensors in the sock or insole as the user performs their activities. A heat map that collects data via bluetooth shows the load applied to the ball or heel of the foot. Such data on pressure can be used to diagnose problems where pressure is seen to be applied improperly (such as in the case of asymmetrical loading) or to a dangerously high degree. FootSens may be able to guide doctors and physical therapists in the treatment decision making process. The researchers plan to use the data to evaluate relationships between work activities and strenuous pressure patterns, allowing for the development of more informed methods to alleviate physical toll on the body.
Accessibility was a priority in designing FootSens. By minimizing costs as much as possible and creating an insole that can be created in various sizes, FootSens targets a large population size – most of the population, after all, can benefit from the mitigation of effects caused by physically-taxing jobs. While COVID-19 might be a minor deterrent, the team is looking forward to continuing to value accessibility while broadening the scope of their foot sensor in the future, stride by stride.
For more information about this project, please email Professor Grace O’Connell (g.oconnell@berkeley.edu).