Wireless and Passive Magnetoelastic-Based Sensor for Force Monitoring of Artificial Bone

A novel magnetoelastic-based sensor (MBS) is proposed in this paper to monitor the force of artificial bone (AB) using magnetoelastic material as the sensing element based on the inverse magnetoelastic effect. The MBS is embedded inside the AB using novel 3-D printing technology (N3DPT). Seven ABs are fabricated by N3DPT and tested by self-developed experimental devices to select the optimum output position of MBS and explore the relationship between the external force working on the AB and the varying value of output power (VOP) caused by the MBS. The applied force of the AB covered by biological tissue is also further monitored using MBS. Results indicate that the middle position ( $h=0$ ) of the AB can fully express the performance of MBS and clearly reflect and monitor the applied force of the AB using a wireless and passive method. An increase of external force working on the AB can cause a rise in output power of the sensing coil which is 0.5 dbm of the VOP under 100 N external force. This further demonstrates that the MBS can efficiently monitor the force of AB and prosthesis in vitro and in vivo .