Abstract Correctly torquing bone screws is an important factor in achieving positive patient outcomes during orthopaedic surgery. A torque-limiting smart screwdriver concept has been proposed, and ongoing work being undertaken to model the screwing process allow work. These models require experimental validation, so a test rig was developed. The magnetostrictive torque sensor this affected by m...

Magnetostriction occurs in the most ferromagnetic materials and leads to many effects [1,2]. The most useful one to refer to is the Joule effect. It is responsible for the expansion (positive magnetostriction) or the contraction (negative) of a rod subjected to a longitudinal static magnetic field. In a given material, this magnetostrain is quadratic and occurs always in the same direction what...

The existence of a deformation and magnetization minimizing the magnetostrictive free energy is given. Mathematical challenges are presented by a free energy that includes elastic contributions defined in the reference configuration and magnetic contributions defined in the spatial frame. The one-to-one a.e. and orientation-preserving property of the deformation is demonstrated, and the satisfa...

The present paper describes the work done at SLAC for the magnetostrictive wire spark chambers of SPEAR, LASS and the two-meter streamer chamber. All three are CAMAC systems based on the use of a time digitizer module with different interfacing techniques into three different computers (Sigma 5, PDP-9, PDP-11). Of particular interest is a display controller module that permits wide selection of...