ISSN (Online) : 2319 - 8753 ISSN (Print) : 2347 - 6710 International Journal of Innovative Research in Science, Engineering and Technology Volume 3, Special Issue 3, March 2014 2014 International Conference on Innovations in Engineering and Technology (ICIET’14) On 21 st & 22 nd March Organized by K.L.N. College of Engineering, Madurai, Tamil Nadu, India Copyright to IJIRSET www.ijirset.com 1188 M.R. Thansekhar and N. Balaji (Eds.): ICIET’14 ABSTRACT—Surface Electromyography (sEMG) is a technology to measure the bio-potentials across the muscles. The true prospective of this technology is yet to be explored. In this paper, we used a simple and economically constructed sEMG sensor. These sensors were used to determine the differences in the Electromyography (EMG) signal patterns for investigating the loss in the muscle strength of a half paralytic person. Signals have been retrieved from the Flexor carpi radialis muscle of both the arms of a half paralytic person. The sEMG data acquisition is done using the soundcard of a computer, hence reducing the need of additional hardware. Finally, the data is used to analyze the relationship between electromyography and loss of strength due to paralysis. Our results clearly show the difference between muscle strength of the two hands, healthy hand and paralytic hand, of the same half paralytic individual. KEYWORDS—Surface Electromyography; muscle strength; stroke; paralysis; Flexor carpi radialis muscle. I. INTRODUCTION Surface electromyography (sEMG) is one of the easy and reliable ways of studying the muscle activity by observing the bioelectrical signals. Its various applications like - diagnosis of neuromuscular abnormalities [1]-[4], in the field of prosthetics [5] and for the study of muscle dynamics [6]-[8]; have made it invaluable for the medical community as well as for the modern technology developers [9]-[13]. Though a lot of work has been done regarding the EMG based study of upper limbs muscles [14]-[16], but very few research have been done regarding the effect of stroke on the muscle activity [17]- [19]. Moreover, very few similar researches have been done in a non-laboratory/ non-ideal environment. Retrieval of EMG signals using sEMG sensors, in a non- ideal environment, is often a challenging task. This is because the amplitude of sEMG signal of a healthy person is of range 10μV to 5000μV and lies in the frequency range 10Hz to 500 Hz [20]. Moreover it has very small SNR and the raw sEMG signal contains interference, also called hum, from 50Hz/60Hz AC power line sources [21]. Due to these reasons some proper precautions should be taken in order to minimize these interference noises. In addition, the sEMG signals become weaker for the muscles of physically challenged persons. In order to study the characteristics of these muscles, in terms of sEMG, some efficient but economic sEMG retrieval circuitry is required. In this paper we are presenting a study on the effect of stroke on muscle activity with the help of economically developed sEMG sensors. The developed hardware has been used to observe the effect of stroke [22] on a patient. sEMG data have been taken from muscles of the patient who had a stroke recently. Another set of data have also been collected from the same patient after a recovery period of SEMG Based Study On The Difference In The Muscle Strength Of A Half Paralytic Person Due To Stroke Abhishek Jha 1 ,Mrinal Sen 2 Department of Electronics Engineering, Indian School of Mines, Dhanbad, Jharkhand, India Department of Electronics Engineering, Indian School of Mines, Dhanbad, Jharkhand, India