Pengukuran impuls tegangan pada saraf sensorik manusia dengan memberikan rangsangan listrik serta pemodelannya dalam rangkaian impedansi

MARENTEK, Ferry, Dr.dr. Djoko Prakosa

2004 | Tesis | S2 Teknik Elektro (Magister Teknik Instrumentasi)

Penelitian ini bertujuan untuk mengukur amplitudo impuls tegangan dari saraf sensorik manusia, sebagai akibat dari pemberian stimulasi pulsa tegangan DC yang bervariasi. Kemud ian untuk mengetahui kecepatan saraf menghantarkan impuls, serta untuk membuktikan adanya perbedaan kecepatan saraf bila diberi pulsa tegangan DC yang bervariasi sebagai penstimulasi. Untuk mencapai tujuan diatas maka digunakan suatu perangkat alat yang terdiri dari; Stimulator, Penguat impuls (AVB-8), Elektrode, Oscilloscope, Addscope, Isolator dan satu perangkat Komputer dan beberapa peralatan diatas terlebih dahulu dikalibrasi sebelum digunakan. Tegangan berbentuk pulsa yang dapat diatur-atur baik amplitudo, lebar pulsa maupun frekuensi detaknya digunakan sebagai perangsang. Saat pengukuran, elektrode ditempatkan pada saraf sensorik di tangan kemudian dikaki. Pulsa tegangan stimulasi dinaikkan secara bertahap, mulai dari 2V s/d 30V ditangan dan 3V s/d 31V dikaki. Pengukuran kecepatan saraf dilakukan ditangan pada jarak 20cm dan 40cm terhadap sumber tegangan stimulasi. Untuk tampilan dan perekaman digunakan komputer dengan menggunakan program-program MatLab Ver.6.5.1 Rel.13 untuk penerima dan pengolah signal, kemudian ACDS Ver.6, Adobe Photoshop Ver.8 untuk pengolah gambar signal. Hasil penelitian menunjukkan bahwa kecepatan saraf 66,67 m/d pada tegangan stimulasi 6V dan kecepatan saraf menjadi lebih tinggi jika tegangan stimulasinya semakin tinggi. Demikian pula dengan tanggapan impuls saraf dalam (mV), amplitudo nya menjadi lebih tinggi. Untuk perancangan alat pendiagnosa ataupun terapi saraf dapat digunakan tegangan-tegangan 6Vs/d 7V atau 20Vs/d 28V, dimana pada tegangan-tegangan ini tanggapan impulsnya relatif stabil.

This research is aimed at measuring of voltage impulse amplitudo from the sensory nerves as a result of giving the stimulating pulse of varied voltage. In addition , the purpose of the research is to know the speed of nerves in transmiting impulse, and also to prove the difference of nerve’s speed when a varied voltage pulse as a stimulus was given. In order to achieve the aims of this research, sets of instruments were used. Those were: Stimulator, Signal amplifier (AVB-8), Electrode, Oscilloscope, Addscope, Isolator, and a set of Computer, which have been calibrated before. The voltage in the forms of pulse of which either amplitudo, pulse width, time interval, or beat frequency can be adjusted was used as the stimulus. When the measuring was conducted, the electrode was put on the sensory nerves in hand and foot respectively. The voltage pulse was then increased gradually from 2V – 30V in hand and 3V – 31V in foot. The measuring of nerve’s speed was carried out in hand in which 20 cm and 40 cm distance to the source of stimulating voltage. Recording and display were in the computer using MatLab ver.6.5.1 Rel.13 program to receive and process signal, and ACDS Ver.6, Adobe Photoshop ver.8 programs to process pictures of the signals. The result of this research shows that the nerve’s speed is 57,14 m/s in stimulating voltage 6V, and nerve’s speed increase if the stimulating. Voltage is high; the same is true with nerve impulse respons in mV in whics the amplitudo is becoming high. In creating tools for diagnose or nerve therapy, 6V – 7V or 20V – 28V voltage can be used, in which impulse responses are relatively stable. It is necessary to apply the curve fitting technique because the wave data was garned through ‘capture’, and also to get the best wave model with the smallest MSE value from the raster data of this capturing result. The order 6 Gaussian model was derived as the best suggested model to illustrate impulse respons formulae. Therefore, the impedance circuit model of the human skin consists of 6 series circuits consisting RC parallel which have a series circuit with an R of each.

Kata Kunci : Kelistrikan Syaraf,Syaraf Sensorik Manusia,Kecepatan Impuls, Sensory nerve, Stimulus, Amplitudo.