Several studies have focused on the use of inertial measurement units (IMUs) to detect heel slips occurring on a straight and level path, neglecting toe slips that occur at toe off. Existing Automated Slip Detection MethodsĪ number of methods for detecting slips have been described in the literature. The addition of an automated slip detection system would make the MAA test more objective and accurate.ġ.2. We also suspect that MAA test observers disproportionally identify larger slips because these are easier to see. These observers likely introduce variability in the results based on differences in vigilance and/or skill. However, there is one major limitation to this test method, which is that it relies on the subjective assessment of a human observer to determine when a participant has experienced a slip. These findings are driving greater interest in the MAA test. The MAA test has also been used to evaluate how quickly these advanced composite materials lose their slip resistance performance, highlighting a potential limitation of this technology. A field study with 110 home healthcare workers found that the group wearing footwear that performed well on the MAA test reported nearly 80% fewer falls compared to a matched group wearing their own footwear. These advance materials have also been shown to perform better than conventional footwear in real-world conditions. In fact, our findings have shown that slip resistance varies widely among commercially available winter footwear and that a new generation of slip resistant winter footwear that incorporates composite materials performs much better than most other footwear available on the market. Our testing has shown that the MAA test is able to identify differences in slip resistance performance that the SATRA test is unable to find. The slip resistance of the footwear is defined by the maximum slope angle (measured in degrees) that the participant can walk up and down without slipping. Recently, our team at the KITE Research Institute (Toronto Rehabilitation Institute, University Health Network) developed the human-centered Maximum Achievable Angle (MAA) test, which involves participants walking up and down ice-covered inclines while wearing test footwear in a simulated winter environment. Ecological validity for a test refers to whether the test results are representative of performance in real-life settings. Unfortunately, this test has been found to have poor ecological validity likely because it is unable to simulate the complex dynamics of human walking. This method measures the coefficient of friction by applying a specified normal force pressing the test footwear onto a test surface and then moving the test surface horizontally at a set constant speed using the SATRA STM 603 Slip Resistance Testing machine. The current industry standard for measuring footwear slip resistance is a mechanical test developed by the SATRA Technology Centre and is recognized by ASTM International. However, assessing the slip resistance on icy surfaces remains challenging. Slip-resistant footwear can prevent falls on icy surfaces. In addition, the algorithm was able to accurately classify backward toe slips, forward toe slips, backward heel slips, and forward heel slips with F 1 scores of 97.3%, 54.5%, 80.9%, and 86.5%, respectively. Our algorithm was able to detect slips with an overall F 1 score of 90.1%. A total of approximately 11,000 steps from 9 healthy participants were collected, which included approximately 4700 slips. The two classifiers were trained, optimized, and validated to classify toe slips and heel slips, respectively. Our algorithm segmented these data into steps and extracted features as inputs to two linear support vector machine classifiers. ![]() Kinematic data were collected from nine healthy young adults walking up and down on ice surfaces in a range from 0° to 12° using an optical motion capture system. The objective of this study was to develop and evaluate an automated slip detection algorithm for walking on level and inclined ice surfaces to be used with the MAA test to replace the need for human observers. However, the MAA test requires the use of a human observer to detect slips, which increases the variability of the test. Winter footwear slip resistance can be measured by the Maximum Achievable Angle (MAA) test, which measures the steepest ice-covered incline that participants can walk up and down without experiencing a slip. Slip-resistant footwear can prevent fall-related injuries on icy surfaces.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |