Smart mug to measure hand's geometrical mechanical impedance

• Published in: 2011 Annual International Conference of the IEEE Engineering in Medicine and Biology Society Vol. 2011; pp. 4053 - 4056
• Main Authors: Hondori, H. M., Ang Wei Tech
• Format: Conference Proceeding Journal Article
• Language: English
• Published: United States IEEE 01.01.2011
• Subjects: Biomechanical Phenomena; Electric Impedance; Force; Hand - physiology; Humans; Impedance; Impedance measurement; Mathematical model; Mechanical variables measurement; Monitoring, Physiologic - instrumentation; Motor Skills; Muscles
• ISBN: 9781424441211; 1424441218
• ISSN: 1094-687X; 1557-170X
• DOI: 10.1109/IEMBS.2011.6091007

A novel device, which looks like a mug, has been proposed for measuring the impedance of human hand. The device is designed to have convenient size and light weight similar to an ordinary coffee mug. It contains a 2-axis inertia sensor to monitor vibration and a small motor to carry an eccentric mass (m=100gr, r=2cm, rpm=600). The centrifugal force due to the rotating mass applies a dynamic force to the hand that holds the mug. Correlation of the acceleration signals with the perturbing force gives the geometrical mechanical impedance. Experimental results on a healthy subject shows that impedance is posture dependant while it changes with the direction of the applied perturbing force. For nine postures the geometrical impedance is obtained all of which have elliptical shapes. The method can be used for assessment of spasticity and monitoring stability in patients with stroke or similar problems.