Estimation of tendon slack lengths of quadriceps based on a least squares optimization

Based on the force transfer relationship from muscle to tendon, a chart determining a normalized tendon force is developed. The experimental data of knee extension moment obtained at maximum isometric contractions are prepared to characterize one´s musculo-tendon properties. An optimization algorithm is introduced, which searches the tendon slack lengths of quadriceps by minimizing the differences of calculated knee extension moment with experimental data. The optimized results which are obtained using various search range limit are summarized and analyzed.