1_PENDAHULUAN FI365 SISTEM INSTRUMENTASI. Program Studi Fisika. Waslaluddin, dkk

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1 1_ FI365 SISTEM Program Studi Fisika Waslaluddin, dkk

2 ISI KULIAH Definisi dan Terminologi Prinsip Transduksi Fisika dan Kimia Klasifikasi Sensor Perkembangan Sensor 1

3 DEFINISI DAN TERMINOLOGI 2

4 3 DEFINISI to sense : merasakan Sensor adalah suatu perangkat (device) atau sistem (sensor system) yang dapat merasakan suatu besaran fisika, kimia atau biologi dan merespon besaran tersebut dalam bentuk besaran fisika, kimia atau biologi lainnya atau mengkonversi besaran yang dirasakan menjadi besaran lainnya. Sensor head Transducer adalah suatu perangkat (device) dapat mengubah (to convert) suatu energi atau besaran fisika, kimia atau biologi ke bentuk energi atau besaran lainnya Energy Converter atau Modifier

5 DEFINISI Radiasi Kimia Mekanik k Radiasi Kimia Mekanik k 4 Magnetik Termal Elektrik Magnetik Termal Elektrik

6 DEFINISI Transduser: Sensor dan Aktuator Sensor : Sebagai transduser input misal : microphone, thermocouple, RTD, pitot tube dsb Aktuator : Sebagai transduser output misal : loud speaker, control valve, damper, motor listrik dsb 5

7 6 DEFINISI Sistem Kombinasi dua atau lebih elemen, subsistem atau bagian yang diperlukan untuk menghasilkan suatu fungsi Untuk berinteraksi dengan lingkungan (real world) suatu sistem memerlukan Sensor : perangkat input Aktuator : perangkat output Pemroses : sinyal informasi dan pengetahuan Sensor merespon dalam bentuk sinyal yang dapat diproses lebih lanjut seperti Amplifikasi, pemfilteran, transmisi, pemrosesan dan displai

8 DEFINISI Sensor, sistem sensor atau transduser merupakan antar muka (interface) antara besaran-besaran fisika pada fenomena alam, proses, mesin, lingkungan dan sebagainya ke suatu sistem pengukuran, monitoring dan pengontrolan Variabelvariabel fisika, kimia atau biologi Sensor atau Sistem Sensor Variabelvariabel fisika, kimia atau biologi (umumnya besaran listrik seperti arus atau tegangan) 7

9 DEFINISI Measurement The process of comparing an unknown quantity with a standard of the same quantity or standard of two or more related quantities Measurement Science the systematic study and organization of the methods by which INFORMATION is gathered from the PHYSICAL world 8

10 DEFINISI Instrument Engineering the systematic design and manufacture of reliable, cost effective measuring instrumentation that fulfills a given measurement specification 9

11 10 Intelligent Sensor Intelligent Kemampuan untuk mengkombinasikan A priori knowledge (available before experience) & Adaptive learning (from experience) Intelligent sensor system Suatu sistem sensor yang memiliki kemampuan menyimpan informasi sebelumnya dan adaptasi menyesuaikan dengan keadaan yang saat ini dan akan datang Beberapa definisi yang ada A sensor that is capable of modifying its internal behavior to optimize the collection of data from the external world [Whi97] Konsep adaptasi dan kompensasi adalah sentral filosofi sensor cerdas Suatu perangkat yang mengkombinasikan suatu elemen sensor dan pemroses sinyal pada suatu IC tunggal [PY95a] Sensor cerdas adalah suatu sensor yang memiliki fungsi yang diperlukan untuk menghasilkan representasi yang benar besaran yang dideteksi atau besaran yang dikontrol [1451.2][Fnk00]

12 Prinsip Sub-sistem dalam suatu Sistem Sensor Cerdas [BW96] Elemen primer (primary sensing elements) Kontrol eksitasi Amplifikasi Pemfilteran analog Konversi data Kompensasi Pemrosesan informasi digital Pemrosesan komunikasi digital 11

13 Prinsip Sub-sistem dalam suatu Sistem Sensor Cerdas [BW96] 12

14 E-nose 13

15 PRINSIP TRANSDUKSI FISIKA DAN KIMIA 14

16 DEFINISI 15 Transduksi: Pengubahan dari satu energi ke energi lain D I R E C T C O M P L E X energi termal energi elektrik energi mekanik energi elektrik energi radiasi energi elektrik energi magnetik energi elektrik energi kimia energi elektrik energi kimia energi mekanik energi elektrik energi mekanik energi termal energi elektrik Kimia Magnetik Radiasi Elektrik Mekanik Termal

17 SINYAL DOMAIN ENERGI Mekanik : L, A, V, v, ω, a, m, F, P, Torsi, aliran, viskositas Termal : Temp (T), Cp, aliran kalor, keadaan materi Elektrik : V, I, Q, R, L, C, E, ε. Magnetik : H, B, Φ, χ, µ, dipol momen (µ m ). Radiasi : Warna, Int., T, R, A, refraktif indeks (n), koef. ekst.(k) Kimia : Komposisi (x A ), C, kec. reaksi (R), ph, humiditas 16

18 TRANSDUKSI KE PENGLIHATAN (E. RADIASI) thermometers: temperature (T) panjang (L) barometers: tekanan udara (P) panjang (L) scales: berat/massa (m) sudut (θ) kelembaban: puntiran rambut (τ) sudut (θ) indicator dyes: konsentrasi kimia (C) warna photo film: intensitas radiasi (I) kepekatan Ag (ρ) speedometers: kecepatan (v) sudut (θ)??..??.??.. 17

19 TRANSDUKSI KE ELEKTRIK Thermistor Electrochemical Photocurrent Pyroelectric Humidity Length (LVDT) Microphone : temperature resistance : chemistry voltage : light intensity current : thermal radiation voltage : humidity capacitance : displacement inductance : sound pressure??? 18

20 Physical effect: signal energy conversion 19

21 20 m e a s u r a n d loop SENSE THINK - ACT transduce perception to electrical signal SENSOR ACTUATOR transduce signal to heat, displacement, illumination, etc Transducer DAC ADC measure in volts, amps, ohms, henrys, farads, etc. convert from signal to symbol compute control action convert from symbol to signal

22 Capacitance PRINSIP TRANSDUKSI C = q V 21 l C = = ε o d ln A 2 π ε l o ( b / a )

23 PRINSIP TRANSDUKSI Contoh : Level sensor (physical) h V C 2 ε H o o = π ln ( b / a ) ε o,r, b, a, H constant 22 π ( b / a ) [ ε ( H h ) h ] o + ε C = r ln 2 h C V

24 PRINSIP TRANSDUKSI Contoh : Occupancy sensor (physical) x V x 23 C sg, C og : constant x C so V

25 PRINSIP TRANSDUKSI Resistance R A l ( ) ρ T l R = V = i. A 24 R ( ρ, l, A ) R R = = ρ ρ ρ l A l + l A A

26 PRINSIP TRANSDUKSI Contoh : Level sensor (physical) h V ( ) ρ T l R = V = i. A R 25 h h d R V

27 PRINSIP TRANSDUKSI Contoh : Force sensor (physical) F V ( ) ρ T l R = V = i. A R σ E l l = ρ a V ρ l = l F = l a R = ρ R = l 2 V 26 l F σ l R V 2

28 PRINSIP TRANSDUKSI Contoh : Temperature sensor (physical) T V ( ) ρ T l R = V = i. A R bimetal 27 l 2 l 1 T α l R V l R 2 = l 1 1 = ρ [ + α ( T T ) ] l a = l ρ V 2 2 1

29 PRINSIP TRANSDUKSI Contoh : Gas sensor (chem.) C R C CO 28 = w t σ R = = qn µ e l ρ A C CO q σ R 1 l σ w. t

30 PRINSIP TRANSDUKSI Contoh : Humidity sensor (chem.) %H 2 O Z %H 2 O C 2, R 2, C 3, R 3 constant 29 Z R + j ω C = 1 %H 2 O pore C 1, R 1 Z

31 KLASIFIKASI SENSOR 30

32 KLASIFIKASI SENSOR Proprioception (Internal state) v.s. Exteroceptive (external state) measure values internally to the system (robot), e.g. battery level, wheel position, joint angle, etc, observation of environments, objects Active v.s. Passive emitting energy into the environment, e.g., radar, sonar passively receive energy to make observation, e.g., camera Contact v.s. non-contact Visual v.s. non-visual vision-based sensing, image processing, video camera 31

33 Proprioceptive Sensors Encoders, Potentiometers measure angle of turn via change in resistance or by counting optical pulses Gyroscopes measure rate of change of angles fiber-optic (newer, better), magnetic (older) Compass measure which way is north 32 GPS measure location relative to globe

34 Classification of Sensors Stimulus : physical, chemical & biological measurand (energy) Transduction effects : Active (self-generating) vs Pasive (modulation) Scale of measured properties : scale of measurands Sensing constraints : ways of measurement Field of applications : e.g. automotive, industrial, robotic, etc. Materials 33

35 Stimulus Radiasi Kimia Mekanik Magnetik Termal 34 Elektrik Sensor measurand output signal measurand Sensor power supply output signal

36 Transduction effect 35

37 Transduction effect 36

38 Scale of measurands 37

39 Sensing constraints 38

40 Radiant Sensors Electromagnetic Spectrum Visible Spectrum 700 nm 400 nm 39

41 Radiant Sensors Electromagnetic Spectrum Light Sensors Photodiodes Phototransistor Photoresistors Cooled Detectors Thermal Detectors Golay Cells Thermopile Sensors Pyroelectric Sensors Bolometers Active Far-Infrared Sensors Gas Flame Detectors Radiation Sensors Scintillating Detectors Ionization Detectors Ionization Chambers Proportional Chambers Geiger Müller Counters Semiconductor Detectors 40

42 41 Occupancy and Motion Detectors Mechanical Sensors Ultrasonic Sensors Microwave Motion Detectors Capacitive Occupancy Detectors Triboelectric Detectors Optoelectronic Motion Detectors Visible and Near-Infrared Light Motion Detectors & Far-IR Motion Detectors Position, Displacement, and Level Potentiometric Sensors Gravitational Sensors Capacitive Sensors Inductive and Magnetic Sensors LVDT and RVDT Eddy Current Sensors & Transverse Inductive Sensor Hall Effect Sensors & Magnetoresistive Sensors Optical Sensors Optical Bridge & Proximity Detector with Polarized Light Fiber-Optic Sensors & Fabry Perot Sensors Grating Sensors & Linear Optical Sensors (PSD) Ultrasonic Sensors Radar Sensors : Micropower Impulse Radar & Ground-Penetrating Radar Thickness and Level Sensors : Ablation & Thin-Film & Liquid-Level Sensors

43 Mechanical Sensors 42 Velocity and Acceleration Capacitive Accelerometers Piezoresistive Accelerometers Piezoelectric Accelerometers Thermal Accelerometers Heated-Plate Accelerometer Heated-Gas Accelerometer Gyroscopes Rotor Gyroscope Monolithic Silicon Gyroscopes Optical Gyroscopes Force, Strain, and Tactile Sensors Strain Gauges Tactile Sensors. Piezoelectric Force Sensors Pressure Sensors Mercury Pressure Sensor Piezoresistive Sensors Capacitive Sensors. VRP Sensors Optoelectronic Sensors Vacuum Sensors Pirani Gauge Ionization Gauges Gas Drag Gauge

44 Mechanical Sensors 43 Flow Sensors Thermal Transport Sensors Ultrasonic Sensors Electromagnetic Sensors Microflow Sensors Breeze Sensor Coriolis Mass Flow Sensors Drag Force Flow Sensors Acoustic Sensors Resistive Microphones Condenser Microphones Fiber-Optic Microphone Piezoelectric Microphones Electret Microphones Solid-State Acoustic Detectors

45 Temperature Sensors Thermoresistive Sensors Resistance Temperature Silicon Resistive Sensors Thermistors NTC Thermistors Self-Heating Effect in NTC Thermistors PTC Thermistors Thermoelectric Contact Sensors Semiconductor P-N Junction Sensors Optical Temperature Sensors Fluoroptic Sensors Interferometric Sensors Thermochromic Solution Sensor 44 Acoustic Temperature Sensor Piezoelectric Temperature Sensors

46 Magnetic Sensors 45 Direct Sensors Metal-Oxide Chemical Sensors ChemFET Electrochemical Sensors Potentiometric Sensors Conductometric Sensors Amperometric Sensors Enhanced Catalytic Gas Sensors Elastomer Chemiresistors Complex Sensors Humidity and Moisture Sensors Capacitive Sensors Electrical Conductivity Sensors Thermal Conductivity Sensor Optical Hygrometer Oscillating Hygrometer Thermal Sensors Pellister Catalytic Sensors Optical Chemical Sensors Mass Detector Biochemical Sensors Enzyme Sensors

47 Chemical Sensors 46 Direct Sensors Metal-Oxide Chemical Sensors ChemFET Electrochemical Sensors Potentiometric Sensors Conductometric Sensors Amperometric Sensors Enhanced Catalytic Gas Sensors Elastomer Chemiresistors Humidity and Moisture Sensors Capacitive Sensors Electrical Conductivity Sensors Thermal Conductivity Sensor Optical Hygrometer Oscillating Hygrometer Complex Sensors Thermal Sensors Pellister Catalytic Sensors Optical Chemical Sensors Mass Detector Biochemical Sensors Enzyme Sensors

48 PERKEMBANGAN TEKNOLOGI SENSOR 47

49 48

50 Multisensor integration and fusion 49