  Molecular motors walk along filaments until they detach stochastically with a
force-dependent unbinding rate. Here, we show that this unbinding rate can be
obtained from the analysis of experimental data of molecular motors moving in
stationary optical traps. Two complementary methods are presented, based on the
analysis of the distribution for the unbinding forces and of the motor's force
traces. In the first method, analytically derived force distributions for slip
bonds, slip-ideal bonds, and catch bonds are used to fit the cumulative
distributions of the unbinding forces. The second method is based on the
statistical analysis of the observed force traces. We validate both methods
with stochastic simulations and apply them to experimental data for kinesin-1.
