Skin Modeling Analysis of a Force Sensing Instrument-Assisted Soft Tissue Manipulation Device

Instrument-assisted soft tissue manipulation (IASTM) is a form of manual therapy which is performed with rigid cast tools. The applied force during the IASTM process has not been quantified or regulated. Nor have the angle of treatment and strokes frequency been quantified which contribute to the overall recovery process. This paper presents a skin modeling analysis used in the design of a novel mechatronic device that measures force in an IASTM application with localized pressures, similar to traditional, nonmechatronic IASTM devices that are frequently used to treat soft tissue dysfunctions. Thus, quantifiable soft tissue manipulation (QSTM) represents an advancement in IASTM. The innovative mechatronic QSTM device is based on one-dimensional (1D) compression load cells, where only four compression force sensors are needed to quantify all force components in three-dimensional (3D) space. Here, such a novel QSTM mechatronics device is simulated, analyzed, and investigated using finite element analysis (FEA). A simplified human arm was modeled to investigate the relationship between the measured component forces, the applied force, and the stress and strain distribution on the skin surface to validate the capability of the QSTM instrument. The results show that the QSTM instrument as designed is able to correlate the measured force components to the applied tool-tip force in a straight movement on the skin model.