1. Results Conclusions Development of an Pronation Controlling Suspension in Running Shoes Caroline de Monasterio, Brandon Jackson, Philip O'Bannon, Robin Giannattasio, Michael Cannamela, Dan Thomas Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, 37235 Motion of the Foot Pronation: the tri-plane motion of simulatneous eversion, abduction and dorseflexsion Supination: the tri-plane motion of simultaneous inversion, adduction and plantarfelxion. Background Running shoes should prevent injury and increase efficiency of a runners gait  The complexity of individual biomechanics make it almost impossible to create a universal shoe  Most running injuries arise from oversupination or overpronation.  Because overpronation is the most common cause of injury, midsole design is the most important component providing cushioning, stability and motion control  Most runners are unaware of their running style which makes it difficult to choose the correct shoe Project Goals Reduce common running injuries such as plantar fasciitis, achilles tendonitis and shin splints/similar stress fractures. Reduce pronation angle in runners who overpronate Achieve this correction by designing an adjustable shoe suspension. Develop a working prototype for our design and test its effectiveness in a motion analysis lab Acknowledgements Our most heartfelt thanks to Dr. Kevin Robinson at the Belmont Physiotherapy Motion Analysis Lab for his useful, practical advice and guidance in the lab. We would also like to thank Narayan Sundaram for his advice on foot diseases. Further acknowledgement to Thunder for his enthusiasm. Anatomical Planes and Transverse Motion –Sagittal Plane: splits foot vertically into left and right section. –Frontal Plane: splits foot vertically into front and back sections. –Transverse Plane: splits foot into top and bottom sections. –Abduction: lateral rotation (away from center) –Adduction: medial rotation (towards center) –Plantarflexion: foot moves down, away from tibia –Dorsiflexion: foot moves upward, towards tibia. –Inversion: The foot twists inwards and upwards –Eversion: The foot twists outwards and upwards Competition Static designs use medial posts of varying stiffnesses to provide support for overpronators, but these designs are not adjustable. The Adidas 1 uses a motor to modulate stiffness in the midsole according to displacement feedback. Drawbacks are the $250 price tag and weight of 15.3 oz (where average running shoe is 12oz) Modeling A particle swarm optimization algorithm was used to find spring placements with the desired stability, shown below. A state space model implemented in MATLAB’s Control Systems toolbox predicts the system response based on pressure map input data. In the graphic below, red is flexion, green is in/eversion and blue is vertical deflection. The above graph shows the angle of pronation during running. Data were collected three times for each shoe. ShoePrototypeAsics TigerAdidas 1 FootRLRLRL Average Pronation14.813.918.328.516.123.4 S. Error1.261.132.480.6520.3010.159 t-score1.561.881.861.530.3030.347 p-value*0.0900.0670.0800.0850.3840.367 Evaluated at alpha=.1, the differences between the means appear to be significant for the prototype and the Asics. We were successful in controlling pronation in our test subject vs. his normal running shoe and the Adidas 1. Further tests should be done to account for subject variability. Future designs should start with the development of a variable stiffness element and requisite control system.