Patent ID: 8449623
Filing Date: 2013-05-28
Classification: A61F

Abstract:
1. A method for aligning a prosthesis, comprising: attaching a hydraulic device to a prosthesis; receiving pressures or moments from sensors as a lower limb amputee walks using the prosthesis, the prosthesis comprises an aligned prosthesis socket described by a first true angle in a first plane and a second true angle in a second plane orthogonal to the first plane; comparing the pressures or moments to a model, the model describes the relationships between pressures or moments to first and second angles of an optimally aligned prosthesis; obtaining the variance between the received pressures or moments and the model; converting the variance into a desired angle in the first plane and a desired angle in the second plane, the desired angles are calculated to reduce the variance between the received pressures or moments and the model; and transferring hydraulic fluid between a first pair of two diagonally placed cylinders with respect to a first axis of rotation to cause angular motion in the first plane, and transferring hydraulic fluid between a second pair of two diagonally placed cylinders with respect to a second axis of rotation to cause angular motion in the second plane to bring the true angles closer to the desired angles, wherein each cylinder receives a piston therein, wherein each piston travels along a cam surface, and wherein each cam surface provides movement of the piston such that the force applied to the piston is parallel to the cylinder and maintains a constant volume of fluid between opposing cylinders.