We conduct on-snow tests to validate the results of the computer model. A differential GPS system allows us to measure the position, velocity, and acceleration of a rider as he travels through a course. The boots are outfitted with foot force sensors that characterize not only the total normal load acting at the boots, but also the distribution between the left and right foot. Video cameras are placed at strategic locations on the hill to measure roll, and allow for the sychronization of the data collection systems. The course consists of two turns, a toe-side and a heel-side, and tests are conducted at low speeds on shallow slopes. 

Differential GPS System
Rider Equipment:   antenna/reciever
                            data transmitter

Ground Station: antenna/reciever
                        data link
                        computer for data collection/processing

Data collected: position, velocity, and acceleration (5Hz)

Equipment provided by: Guttorm Opshaug, GPS Lab, Department of Aeronautics and Astronautics, Stanford University

GRF Sensors (Foot Force Sensors)

Rider Equipment:  inserts in each boot
                           laptop for data collection

Data collected: total normal boot force (Left/Right)

Equipment supplied by: Dr. Robert Whalen, NASA Ames

Video Analysis

Cameras:  Minimum 3
                Positioned strategically about the prescribed course

Data collected: Roll Angle (measured values from frame analysis)
                       Sychronization of GPS, foot force, and roll angle measurements