Gravity is always dragging us down. To keep on top of it, we apply pressure to the surfaces we come into contact with, usually through the soles of our feet. Although short pressure sensitive pedways and force plates have been around for a while, pressure-sensitive flooring is a relatively young concept and opens up some new and unusual applications. Here, we'll take a look at the top 10 applications we've seen for pressure-sensitive flooring.
Top 10 Things You Can Do With a Pressure Sensitive Floor
1. Assess Abnormal Pressure Patterns
Unlike force plates, pressure sensitive flooring allows you to see the differences in pressure between regions of a foot and between feet as well. Patients with diabetes can develop peripheral neuropathy which may leave them with a loss of sensation in the foot. The result is that they are susceptible to foot ulcerations which, in serious cases, can lead to amputations. A pressure-sensitive floor can be used to identify high pressure points or zones under the foot that may lead to ulceration.
In Cerebral Palsy patients, foot deformity and abnormal gait are common pathologies. In some cases (e.g., flat foot), orthotics may be prescribed, and in other cases (e.g., club foot) surgery is required. Pressure information is being used to determine the effectiveness of interventions, categorizing foot pathology, and characterizing patient populations. Especially in the case of young patients, a larger pressure sensitive floor that does not encourage the patient to target the placement of their step helps to capture natural gait and provide the best picture possible to the clinician. While more research is needed to validate the use of pressure information in preventing diabetic foot ulceration and treating Cerebral Palsy pathologies, it has already seen significant application in the field.
2. Custom Orthotics Design and Prosthetic Fitting and Training
While there is a standard process involved in custom orthotics design, there are different approaches and the result is somewhat dependent on skill and experience. As a result, orthotic quality can vary from patient to patient. The process typically involves creating a cast or mold of the patient’s foot while the patient sits -not placing any weight on the foot. The 3D foot model is either digitized, smoothed and CNC-milled or an image is made using the cast or mold and the orthotic is manually fashioned to fit it. In this typical process, foot pressure is not taken into account, except for special instructions given by the podiatrist for providing pressure relief in a particular zone(s).
Foot pressure information can be used to help explicitly localize areas requiring relief and, with the loaded or standing foot shape can then be used to calculate a custom orthotic shape. This takes much of the guess work out of orthotics, with varying density in specified areas of the orthotic providing the desired load distribution. Some intrepid orthotics shops are incorporating pressure information into their design process, but they are currently in the vast minority.
In the prosthetic world, the pressure sensing floor takes on a different role: fitting and gait training. When being fitted for a new lower-body prosthesis, especially for their first time, patients need to develop a feel for how much weight to apply on the prosthetic. The pressure sensing floor can allow them to see, in real-time, whether they are applying the same amount of weight on one foot as the other and whether their strides are symmetrical. This pressure sensing “mirror” can be used to speed up a patient’s familiarity and be helpful to a clinician in identifying when they need to adjust the prosthesis’ fit.
3. Perform Mobility Assessments for Decision Makers
Seniors homes, insurers, and sports teams regularly need to make high-stakes decisions about an individual’s level of care, claim payouts, and timing on back-to-work or return-to-play. Pressure sensing floors can be used to perform general gait and balance assessments. Gait assessments capture a variety of spatiotemporal details about how we walk, including whether we do so symmetrically and can compare your performance against a range of healthy individuals. Pressure sensing information can also let you know if you are putting too much weight on any particular region (e.g., heavy heel strike). Balance assessments (standing still) rely heavily on pressure information to properly track how weight is shifted over time. The movement of the center of pressure is a key feature providing insight into a person’s ability to stay upright, which is relevant to the aging population and also to concussed athletes whose balance serves as an indicator to know when it is OK to “return to play”.
The benefit? The pressure sensing floor is completely unobtrusive – there are zero wearables. This also allows a busy practice to streamline their assessment process while adding a suite of objective measures to back them up when submitting an insurance claim or persuading Great Aunt Matilda that it’s time to think about professional care options.
4. Military Training and Simulation
Training soldiers effectively requires appropriate feedback and a realistic training environment. To reduce costs, militaries are turning to virtual simulation of battlefields. Often in virtual battle simulations, trainees are moving about the space using a controller, whether similar to a standard video game controller or to one built into their mock weapon. Either way, they do not have to exert themselves to move about the space (For example, get on their hands and knees to move through a tight squeeze).
A pressure sensing floor can be used to convert a person’s running-on-the-spot to a forward movement with a speed proportional to the trainee’s exertion (the total force oscillation amplitude) and capture kneeling and prone postures for a greater degree of realism. A pressure sensing floor can also be used in a virtual land mine clearing exercise to let trainees know when they would have detonated an unseen mine. In sniper training, it can provide feedback about the soldier’s recoil after pulling the trigger by looking at recent movement of their center of pressure.
In live training, such as Military Operations on Urban Terrain, pressure sensitive floors installed in the mock buildings can be used to track the position, heading, and posture of each soldier. This requires multiple subject tracking capabilities, which is well suited to a sensor floor, since there are rarely occlusions (i.e., literally stepping on another’s toes) or lighting issues to contend with. In case this sounds like science fiction, Stepscan completed its initial release of a footprint-based multiple subject tracking API this year for its pressure sensor floor tech, providing position, heading, and postural status.
5. Sports Training and Assessment
As the sporting arena becomes increasingly competitive, teams are looking for new ways to get an edge. A common test of explosive lower body strength is the vertical jump. It’s not only useful for athlete assessment in basketball, but also in hockey, American football, and other sports. In the test, your jump height can be calculated from the amount of time you spend in the air (i.e., hangtime). A number of small jump mats exist to support this test. A sensor floor, however, offers the possibility of looking not only at your jump height, but also at your jump form while launching and landing the jump. It can show differences between legs in terms of jump power and also forces applied by different regions of the foot, especially along the heel/forefoot and medial/lateral axes. A sensor floor would also allow athletes to perform the test while moving forward (e.g., for slam dunks) without having to target a particular place to land.
A completely different sports application, which prefers precision over power, is the golf swing. In this scenario, knowing how balance and regional foot pressures change throughout your swing could make the difference between a birdie and a bogey.
In a variety of sports scenarios, where a sensor floor covers all or key portions of the playing space and multiple subject tracking is enabled, much can be learned, not only about foot placement, but also about shifts in balance and regional pressure during key movements. This is an area that is highly untapped.
6. Testing Industrial Designs
In industry, there is a need for being able to see the pressure distribution of a part or object on a surface as feedback to the design process. Automobile tires, for example, have a variety of sizes and tread patterns designed for specific weather conditions or varying levels of road-handling performance. A sufficiently high resolution, high pressure, and high sampling rate sensing floor would be able to convey the degree of uniformity, points of highest and lowest pressure, and how these details change at different speeds, tire inflation levels, etc. In a similar way, shoe sole patterns are designed for particular use cases and can benefit from the feedback of a pressure sensor floor while an individual wearing the test shoes maneuvers appropriately.
7. Shortening Paths and Improving Interactions
In any manufacturing facility, workers must receive the “raw” inputs, perform some work on them and deliver outputs. This process has them moving about the factory floor to collect materials, produce, and deliver completed parts. The layout of the workers, machinery, entrances, and materials will impact worker movement efficiency and thus production efficiency. A pressure sensor floor with multiple subject tracking could help identify inefficient organization of the manufacturing floor by conveying trends in foot traffic, whether during an initial factory setup or throughout the life of the factory, as processes change over time.
Sensor floor technology was considered for monitoring the deck of a ship during an evacuation drill to look for ways to clear personnel faster. In a similar way, it has been suggested that the technology be used to monitor workplace interactions. In one scenario, where employees representing different businesses work in the same space to facilitate collaboration, position tracking can be used to detect low interaction levels and automatically schedule a mandatory meeting to get the conversations flowing again.
8. Getting Into a Secure Facility
There are a variety of biometric authentication technologies in the market now: fingerprint, iris scan, and facial recognition. But all require some kind of prison-esque scanning effort (fingerprinting and mugshots, anyone?). If your biometric signature could be magically acquired as you approach a secure entry access point, it would streamline the entry process and feel less like being booked into a cell for the night. Gait recognition is the process of identifying individuals by the way they walk, a great use case for a sensor floor. Again, there is a lack of occlusion and combined with multiple subject tracking capabilities, multiple individuals can be screened simultaneously. A sensor floor, rather than a small walkway also promotes individuals to walk naturally, which should improve gait consistency.
Since most secured spaces do not already require individuals to remove their footwear before entry, gait recognition for access control should assume the use of shoes. The underlying recognition strategy should focus on aspects of gait other than the shoe pattern. This will help when an individual wears a pair of footwear the system has never seen and keep imposters from bypassing the system by simply “borrowing” someone else’s shoes.
9. Animal Tracking and Health
Like people, animals have needs that could benefit from a pressure sensitive floor. Unlike people, they can’t speak up for themselves very clearly to point out when and where the issues are.
One significant use case we looked into was analyzing the gait of dogs suffering from pain due to arthritis. An increase in the health of their gait could indicate an improvement in their overall wellbeing. Another interesting call we received was from a cat food manufacturer looking to measure limb strength in a cat vertical jump test (sans cucumber) to prove the efficacy of their chow.
On occasion we have been asked if we could track the movement of large animals such as elephants and horses in an outdoor enclosure. Just like humans, animals that see high pressures underfoot can experience health issues. Rhinos in captivity sometimes develop foot disease and one potentially contributing factor is their under-hoof pressures. Of course, to capture natural movement data from animals of any kind is likely to require a large sensor floor space.
When considering whether to use a pressure sensor system for capturing small animal pressure data, we suggest that you ensure that the animal produced foot pressures fall within low and high pressure limits of the device and that the sensor resolution of the device is appropriate for their small foot size. Multiple sensors improve reliability of the measurements and a sensor element may not cover the full area it is assigned, so a tiny footfall might occur between sensors and be missed.
Because the concept of a pressure sensing floor is relatively new, there is a wide variety of unexplored potential applications. Even in fields that have had underfoot pressure information for a while (e.g., gait analysis), there are still many unanswered questions that a pressure sensing floor can help with. We’ve encountered applications such as circus hand standing analysis, pressure sensitive adhesive testing, tai-chi tracking, capture model helicopter landing, quantifying Alzheimer’s wandering behavior, and more.
Pressure sensing floors cover more space than past plantar pressure mats or pads, allowing a broader range of applications. This includes applications that require multiple subject tracking like live military training and workplace interaction monitoring.
Natural Movement Matters
Unnatural movements can invalidate or mislead outcomes. A pressure-sensitive floor avoids the need for patients to target a foot placement and allows them to move normally, even unobtrusively. This encourages more accurate patient assessments and could potentially get you through the door of a secure facility faster.
Regional Pressure Discrimination Matters
Regional pressures can tell you where a high pressure could lead to an ulceration, that while you stand you lean forward too much, or that your jump shot would improve by launching with increased pressure on your left foot.
Together, these qualities make for an insightful tool in the clinic, on the court, or out on the battlefield.
The big question is, “If you had an hour to play with a pressure sensitive floor, what would you do with it?” Leave your ideas in the comments section below.