Humans can easily perform many bimanual dexterous manipulations using a combined action of the dominant hand (DOM) and the non-dominant hand (NDOM). While the control of proximal segments of the arms like elbows and shoulders has been studied, how the brain controls and coordinates such a large number of joints of the distal segments like hands and fingers is studied little. Additionally, measuring full-hand kinematics is challenging, and existing devices like flex sensor-based data gloves and optical trackers using cameras have disadvantages like the requirement of extensive calibration and line of sight problems.
In this thesis, 2 different challenges associated with the control of the DOM and NDOM hands were addressed. As a first step, the challenges associated with measuring the kinematics of the hand were addressed using Electromagnetic tracking sensors (EMTS). Since the measurements are nonlinear, linearization techniques like logarithmic and exponential mapping were explored. However, the EMTS provides an option for only 16 sensors and cannot be utilized for simultaneous bimanual measurement of kinematics. To this end, an IMU-based device was developed to measure bimanual kinematics. The performance was juxtaposed with the EMTS. The results showed that the HKMS could measure kinematics with a maximum error of 2° for static movements and an RMSE of less than 4° for dynamic movements.
Secondly, a comparison of synergies of the DOM and NDOM hands was performed through 3 experiments: 1. Comparison of kinematic synergies of DOM and NDOM hands while performing unimanual tasks. 2. Analysis of bimanual synergies while performing activities of daily living involving bimanual tasks 3. Comparison of fingertip forces and synergies between the DOM and NDOM hands. The results showed no difference between the DOM and NDOM hands in the kinematic tasks. However, the results of the comparison of fingertip forces demonstrated that the differences between the DOM and NDOM hands are evident only when the task demands are greater. Future directions involving experiments to increase task demands in kinematic experiments were proposed.