Gait analysis is a field in which a person's lower limb motion is analysed. Information regarding how pressure is distributed across the foot during motion can provide useful insights into risk factors associated with overuse injuries in athletics as well as the progression of symptoms in diseases such as multiple sclerosis and diabetic neuropathy. Several technologies currently exist for gait analysis in both recreational and clinical settings. However, various limitations associated with current solutions have been identified by experts. Specifically, issue of durability regarding insoles used in clinical settings and the frequent need for their re-calibration were raised as primary concerns. We believe these issues are associated with the sensing mechanism used in these devices i.e. requiring layers/parts in order to detect pressure, and can be overcome by incorporating sensor function as an intrinsic material property, removing the need for multiple components.
We have developed a prototype smart-insole (an insole with an array of sensing elements embedded) using a patented nanocomposite ink developed within the research group. Our sensing elements consist of a single unit and do not rely on any addition layers/parts within the insole. As a proof-of-concept, the device was tested in a real-word setting to monitor the pressure distribution of someone engaging in walking and jogging as a means of exercise. To record the data, an open source-Bluetooth application was used to transmit the data from the sensor electronics and allow us to visualise sensor responses corresponding to the different sensing elements of the insole during both walking and jogging.
From this, we were able to detect pressure being applied to areas of the foot associated with normal gait. In particularly, we are able to identify so called “heel strike” (where the heel is first planted) and “toe off” (when the toe leaves the ground) phases of the walking gait-cycle. These measurements are essential for determining parameters of gait such as step count, cadence and determining symmetry between limbs. In the case of jogging, the sensors located at the ball of the foot display a considerably larger response than in the case when the user was walking. This is to be expected as the area around the ball of the foot is the first to make contact with the ground in the event of jogging. This is in contrast to walking where the heel is the initial point of contact.
In order to demonstrate the ability of the device to act as an assessment tool for gait analysis, the smart insoles were used to monitor pronated (inward leaning) and supinated (outward leaning) gait types (which are associated with a higher risk of lower limb injury). In both cases, the smart-insoles detected the presence of excess pressure being placed on the outside or inside of the foot – characteristics associated with supination and pronation. This demonstrates the potential for our device to be used as a means of both assessing existing issues in gait as well as monitoring the development of symptoms associated with a developing an overuse injury.
We intend to continue to develop the the project towards achieving a commercial outcome in identified target markets. The intended commercialisation route is the formation of a spin-out company focused on the development of a smart insole for recreational sports performance monitoring and physical rehabilitation. The formation of the start-up allows for three viable routes of commercialisation (B2C, B2B, Licencing Agreement within the Spin-out) which will allow for both an economic impact to be made broadly while allowing us to grow the company and generate local employment.
