Reaching Movements in Dynamic Environments: How Do We Move Flexible Objects?

The paper presents an analysis of human reaching movements in manipulation of flexible objects. To predict the trajectory of human hand, a minimum crackle criterion has been recently proposed in literature. A different approach is explored in this paper. To explain the trajectory formation, we resort to the minimum hand jerk criterion. First, we show that this criterion matches well experimental data available in literature. Next, we argue that, contrary to the minimum crackle criterion, the minimum hand jerk criterion produces bounded hand velocity profiles for multi-mass flexible objects. Finally, we present initial experimental results confirming the applicability of the minimum hand jerk criterion in manipulation of multi-mass objects.