Sensor Mekanik SENSOR MEKANIK SISTEM PENGUKURAN SISTEM PENGUKURAN. Dr. Yeffry Handoko Putra, S.T, M.T PRINSIP DASAR

Transkripsi

1 Sensor Mekanik Dr. Yeffry Hanoko Putra, S.T, M.T SENSO MEKANIK 1 1

2 SENSO MEKANIK: Pressure Sensors Mercury Pressure Sensor Piezoresistive Sensors Capacitive Sensors VP Sensors Optoelectronic Sensors Vacuum Sensors Pirani Gauge Ionization Gauges Gas Drag Gauge Velocity an Acceleration Capacitive Accelerometers Piezoresistive Accelerometers Piezoelectric Accelerometers Thermal Accelerometers Heate-Plate Accelerometer Heate-Gas Accelerometer Gyroscopes otor Gyroscope Monolithic Silicon Gyroscopes Optical Gyroscopes Force, Strain, an Tactile Sensors Strain Gauges Tactile Sensors. Piezoelectric Force Sensors SENSO MEKANIK: Flow Sensors Thermal Transport Sensors Ultrasonic Sensors Electromagnetic Sensors Microflow Sensors Breeze Sensor Coriolis Mass Flow Sensors Drag Force Flow Sensors Acoustic Sensors esistive Microphones Conenser Microphones Fiber-Optic Microphone Piezoelectric Microphones Electret Microphones Soli-State Acoustic Detectors

3 4 SENSO MEKANIK: Occupancy an Motion Detectors Ultrasonic Sensors Microwave Motion Detectors Capacitive Occupancy Detectors Triboelectric Detectors Optoelectronic Motion Detectors Visible an Near-Infrare Light Motion Detectors & Far-I Motion Detectors Position, Displacement, an Level Potentiometric Sensors Gravitational Sensors Capacitive Sensors Inuctive an Magnetic Sensors LVDT an VDT Ey Current Sensors & Transverse Inuctive Sensor Hall Effect Sensors & Magnetoresistive Sensors Optical Sensors Optical Brige & Proximity Detector with Polarize Light Fiber-Optic Sensors & Fabry Perot Sensors Grating Sensors & Linear Optical Sensors (PSD) Ultrasonic Sensors aar Sensors : Micropower Impulse aar & Groun-Penetrating aar Thickness an Level Sensors : Ablation & Thin-Film & Liqui-Level Sensors 5 SENSO TEKANAN (PESSUE SENSO): Definisi makroskopis Tekanan (P) = Gaya mengenai permukaan Satuan luas P = F/A Definisi mikroskopis Tekanan (P) berasar teori kinetik gas = Total energi kinetik molekul gas mengenai permukaan persatuan volume P = / (E k /V) = NT Ek = energi kinetik molekul gas V = volume gas N = jumlah molekul gas = konstanta gas T = temperatur gas Satuan tekanan (P): 1 Pa= lb/in = atm= cm Hg. 1 atm=760 torr=101,5 Pa. 1 psi= Pa=0.070 atm.(sistem US)

4 Bellow & Membran Strain-gage Pressure Sensor Z : efleksi r : jari-jari membran S : tensi paa membran g : tebal membran σ : stress paa membran plat tipis Untuk plat : 6 membran Membran/iaprahm Pressure Sensor 7 4

5 Membran/iaprahm Pressure Sensor Defleksi yang kecil itengah-tengah membran jari-jari membran r n berubah Untuk imana 8 Capacitive Transuction C Maka: A = πr A ε o εr = ( ) ( 1 ν ) ( yr = P r ) C= πε ε o Bagaimana transuksi P C? r 0 16Eh r πεoεr r= y( 0 y( rr y( 1 9 Ingat penekatan 1 rr = 1+ x x y( 1 = 1 + y( rr+... 5

6 Capacitive Transuction Sehingga: rr πε = oεr C= πεoεr y( 0 1 πε oεr 1 C= rr+ y y( 1 rr πε oεr ( ) ( 1 ν ) r rr = + 16Eh 6 P 10 πε ε C( P) = πε ε 1 ν + 16E h ( ) atau o r o r P 6 Capacitive Pressure Sensor 11 6

7 Piezoresistive Transuction 1 Piezoresistive Transuction transversal longituinal an are the perpenicular/transversal an parallel/longituinal components of stress 1 an are the perpenicular an parallel piezoresistive coefficients 7

8 Piezoresistive Transuction - Circuit a & c // stress b & stress 14 Piezoresistive Transuction - Circuit 15 One chip Si-Piezoresistive sensor an signal conitioning Pressure range: up to 5, bar Absolute Operating temperature: -40 to 15 C Supply voltage: 5 V ± 0.5 V Transfer function: linear, ratiometric Accuracy over full-scale: 1 % full span (10 to 85 C) 8