A Method for Precise Placement of Hose Models

A method is presented for precise mounting of a hose model with any specified twist. Once mounting points and directions are specified, a hose of a specified length can be developed using discrete beams. A divide and conquer approach is employed to position, orient, decouple the free end of the hose model in a twist free state that is then twisted to a specified angle. The development of the kinematic elements necessary to do this is presented. Some Cosserat models have been shown to branch into multiple solutions while the method presented here has always converged to the minimum energy solution. The method for linking the hose model to other linkages is discussed as well one common error committed by users in implementing the link.

In order to model the torsional properties of the hose, the torsional stiffness must be modified. A method for doing this using digital scans is discussed. Failure to consider preset and hysteresis of the hoses can cause considerable error in predicting interference as is demonstrated. Simply taking the mount orientations out of a common plane can cause significant stress to build up in the model from torsional coupling during a simple linear translation.