Novel Interaction Control in Adolescent Idiopathic Scoliosis Treatment Using a Robotic Brace

Abstract

Adolescent Idiopathic Scoliosis (AIS) may affect the quality of the patient’s life if it is left untreated. Bracing is prescribed to halt or reduce the curvature progression and avoid surgery. However, the in-brace correction pressure remains unclear, and it is controlled passively by tightening/losing the brace’s strap. Computational modeling has recently attracted researchers’ attention to predict and optimize the AIS bracing treatment. In this paper, a Multi Body-Finite Element (MB-FE) Simscape model and an analytical model of the AIS bracing treatment are created. The MB-FE Simscape model is used to predict the in-brace correction pressure. Furthermore, a Novel Position-based Impedance Control (NPIC) is proposed to control the dynamic interaction between the robotic brace and torso. In this method, the error between the desired and estimated impedance parameters is involved in the controller design to improve the performance of the typical PIC in terms of pose tracking and impedance model tracking. In-vivo data from the literature and numerical simulations are used to validate the MB-FE Simscape model and analytical model. The performance of the proposed controller is verified using numerical simulations in terms of pose tracking and impedance model tracking.