A novel surfing performance quantification system and multi-sensor instrumented surfboard: A proof-of-concept

• Four performance indicators and their combinations are proposed to quantify the Surfer-Board-Wave combo’s performance. • An instrumented surfboard capable of measuring its own movements and deformation is engineered and manufactured. • Performance indicators' results showed interest in quantifying competition criteria and in confirming elite coaches' ideas. • Instrumented surfboard showed differences in the tail behavior depending on the maneuver performed and on the wave’s direction. Despite the last Olympic Games and a recent interest in cutting-edge training, surfers and equipment manufacturers don't have any tool guaranteeing them a consistent Surfer-Board-Wave (the combo) match, mostly due to the incapacity to monitor the mechanical behavior of the board. The aim of this research is to develop methods describing both the combo's performance and the board's mechanical behavior. To do so, an instrumented surfboard is engineered, measuring its rigid-body motions and deformations, synchronized with propositions of performance indicators to describe the performance of the combo. A surfboard is made with a built-in electronic system governing strain-gauges, IMU (Inertial Measure Unit) and Bluetooth communication. To quantify performance, the notion of Jerk is introduced and applied to the surfer and the board. The muscle activity of the surfer is recorded as a performance indicator. The yaw-rotation of the board is recorded as an indicator of surfing radicality. It is proposed to illustrate these indicators with real condition surfing. The instrumented surfboard proved proper functioning during testing, and the mechanical behavior of the board's tail was clearly identified. The performance indicators, Board-Jerk, Surfer-Jerk, Muscle Activity and board’s Radicality are measured and combined into discriminators propositions constituting a world first attempt of a quantified description of the combo Surfer-Board-Wave performance.