Assessing Torsional Deflection of Alpine Skis A Proof of Concept Utilizing Printed Electronics in a Laboratory Setting

Recently, a novel PyzoFlex ski prototype has been developed for detecting the curvature characteristic of alpine skis arising due to the ski bending. However, the torsional deflection components have not been considered so far. Therefore, the objective of this study was to evaluate the feasibility of detecting torsional deflections using a parallel sensor layout. The sensor system used involved twelve sensor elements divided into two rows: a left row (L1 to L6) and a right row (R1 to R6). The prototype underwent standardized deformations performed by a robot, including central bending (CB), edge left (EL), and edge right (ER), repeated over 12 cycles. In modes EL and ER, the skiing-like simulation involves combined loads of bending and torsion, whereas mode CB exclusively includes pure bending. The peak difference value was calculated by subtracting the corresponding sensors in parallel [(Li - Ri) for segment i = 1 to 6] at the point of maximal deflection during CB, EL, and ER. This was followed by an analysis of variance (ANDVA) to identify the segments exhibiting a significant difference in terms of torsion. The results indicate an opposite sign in the mean peak difference at EL and ER, except for segment 1, while the mean peak difference at CB is consistently close to zero across all segments. The observed difference between parallel sensors effectively distinguishes between CB, EL and ER across all six segments, with a p-value of less than 0.001. This indicates that the prototype demonstrates a high level of precision in detecting and discriminating torsional deflection. Further investigations incorporating a “gold standard” reference will be conducted to determine whether the prototype can accurately and validly detect torsional deformations.