Novel experimental characterisation of bouncing and jumping forces

Until now state-of-the-art facilities for measuring human-induced dynamic forces comprised typically equipment for direct measurement of bouncing and jumping forces, made of a single or several force plates mounted on a rigid laboratory floor. Artificial laboratory conditions and constraints imposed by the direct measurement systems, such as small measuring area of a force plate, can exert a strong influence on human ability to bounce and jump naturally, and thereupon may alter corresponding ground reaction forces. However, when dealing with issues like vibration serviceability of real full-scale structures such as grandstands, floors and footbridges, there is a growing need to estimate loads applied directly by occupants under a wider range of conditions in outdoor environments. This paper thus presents a novel method to utilise 'free field' measurement of human bouncing and jumping forces continuously in time using motion capturing technology. This kind of data is crucial for establishing a new generation of probability based mathematical models for bouncing and jumping forces. These are to be used in vibration serviceability of civil engineering structures occupied and dynamically excited by bouncing/jumping humans, such as floors and grandstands.