A stall detection method and system for a stepper motor ascertains a stalled condition according to current rise time of the windings. Further, a photosensitive resin composition comprising a resin having fluorine atom-containing groups and ethylenic double bonds, a resin having silicon atom-containing groups and ethylenic double bonds, a radical initiator, and an alkali-soluble photosensitive resin having at least three ethylenic double bonds per molecule. The inverse triangular is maintained to not bend the artificial limb joint until the user’s forefoot land down again for each step.