DR. GYURCSEK ISTVÁN Sensors Sources and additional materials (recommended) Lambert Miklós: Szenzorok elmélet (ISBN 978-963-874001-1-3) Bp. 2009 Jacob Fraden: Handbook of Modern Sensors (ISBN 978-1-4419-6465-6) Springer NY. 2010 S. Tumanski:Principles of electrical measurement, CRC Press 2006. ISBN 0-7503-1038-3 Máté J.: Méréstechnika 1. PTE PMMIK, ERFP-DD2001-HU-B-01 Dr. Petróczky Károly: Bevezetés a nyúlásmérő bélyeges méréstechnikába, SZIE,Gödöllő http://gyurcsekportal.hu/mik.html 1 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Introduction Measurement Collect information about one or more process characteristics Comparison with etalon ( benchmark ) direct or indirect Measuring Device IN Signal Sensor Signal Conditioning Signal Processing Data Display OUT Thermistor Temperature Meter (example) Measuring Device θ IN Thermistor Linearization Circuit A/D Converter DSP 21,6 o C OUT 2 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Positioning (Energy Approach) Transducer converts one form of energy to another Sensor phisical param electrical output Actuator electrical input phisical output Deformation (change in shape) Voltage Piezoelectric disk 3 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Classification of Sensors (Miller-index, ) Sensor Models (examples) Sensor Groups, Signal Transmission of Sensors (Overview) Static and Dynamic Characteristics (char. uncertainties) Sensor Types and Application Examples 4 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Classification (Energy Approach) "If you have a lot of things, they have to be systematized..." ENERGY APPROACH Conjugated variable pairs f = generalized force h = d h dt generalized current (velocity) System f j h j * Electrical Voltage (U) Current (Q* I) Mech. (translation) Force (F) Velocity (x* v) Mech. (rotation) Torque (M) Angular velocity (φ* ω) Flow Pressure (P) Volume current (V* q) Thermal Temperature (θ) Entropy current (S*) 5 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Classification (Energy Approach) Sensor as generalized energy transducer two-port Conversion variants h 1 * h 2 * f 1 f 2 f 1 h * 2 Sensor Sensor f 1 Sensor f 2 h 1 * Sensor f 2 h 1 * Sensor h 2 * 6 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Classification with Miller-index Passive sensor needs external (auxiliary) energy Active sensor no need of auxiliary energy Miller-index (crystallography analogy) x = input energy y = output energy z = auxiliary energy Possible types of energy in nature Radiation energy Mechanical energy Heat energy Electrical energy Magnetic energy Chemical energy Miller-index notation (x,y,z) rad mech therm el mag chem Sensor variations N x N y N z = 6 6 7 = 252 illustration 7 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Classification with Miller-index 12 (10!) types are interesting for us (out of 252) (x,el, 0) active sensor (x, el, el) passive sensor Examples in Figure 1. thermocouple (therm, el, 0) 2. ph-meter (chem, el, 0) 3. PV cell (rad, el, 0) Actíve 4. Potentiometer (mech, el, el) 5. Photoresistor (rad, el, el) 6. pf (cosφ) meter (el, el, el) 7. Magnetoresistor (mag, el, el) Passíve 8 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Classification of Sensors (Miller-index, ) Sensor Models (examples) Sensor Groups, Signal Transmission of Sensors (Overview) Static and Dynamic Characteristics (char. uncertainties) Sensor Types and Application Examples 9 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Modeling of Sensors modifying input noise input Output of static part signal input static model dynamic model signal output K: scalar factor of input signal N(I): sensor transfer function I M : superimposed input signal of nonlinearity K M : scalar factor of nonlinearity a: offset I I : noise input signal K I : scalar factor of noise Output of dynamic part represented by G(s) transfer function 10 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Ex.1 - Strain Gaugins Sensor Model ambient temperature relative strain 11 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Ex.2 Copper-Constant Thermocouple reference temperature measured temperature 12 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Ex.3 Accelerometer Model transverse acceleration measured acceleration 13 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Classification of Sensors (Miller-index, ) Sensor Models (examples) Sensor Groups, Signal Transmission of Sensors (Overview) Static and Dynamic Characteristics (char. uncertainties) Sensor Types and Application Examples 14 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Sensor Groups (THERM,EL,X) (RAD,EL,X) (MECH,EL,X) (MAG,EL,X) (CHEM,EL,X) Metal Resistors Photometers Force, Torque, Pressure Magnetoresistors Elecrochemistry Semiconductor NTC,PTC,pn Radiowave Detectors Position Detectors Galvanic- Magnetic Det. Humidity Detectors Thermocouples IR Sensors Flow Sensors Ionselective Detectors Thermal Switches Quant Detectors Speed Sensors Gas Detectors Accelerometers Acoustic Detectors 15 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Signal Transmission TRANSMISSION METHODS TRANSMISSION MEDIUM REMOTE TRANSMITTER SMART SENSORS Base Band Copper Wire Analogue Transmitters SCADA Systems Carrier Band Optical Fiber Digital Transmitters DCS Systems Wireless Transm. Embedded Technologies ( SCADA: Supervisory Control And Data Acquisition DCS: Distributed Control System ) 16 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Classification of Sensors (Miller-index, ) Sensor Models (examples) Sensor Groups, Signal Transmission of Sensors (Overview) Static and Dynamic Characteristics (char. uncertainties) Sensor Types and Application Examples 17 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Sensor Characteristics Sensor characteristics catalog data (at defined ambient conditions - temperature, humidity, blast ) Static charactetistics Dynamic charactetistics output overload region Features Static transfer factor (sensitivity) 3 regions of (typical) static characteristics Inoperative (below noise limit) Operation region Overload region output operaive region measurement region overload region Sensor fault (deviation from the characteristic) H, h: abs-, rel. error h op accuracy class (referred to meas. range) 18 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Static Errors 1 (A) Hysteresis error (B) Repetition error n-th cycle h hist h hist(partial) < h hist 1-st cycle error measured in same direction 19 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Static Errors 2 (C) Linearity error (theoretical, referred, indept, regress.) (D) Resolution error E. Creep (kúszás) B=const. K=K(t) instability F. Null point shift (parallel shift) B = 0 K > 0 G. Sensitivity change E=E(t) aging 20 gyurcsek.istvan@mik.pte.hu 2018.07.09.
transient temp error Static Errors 3 (I) Temperature dependency (temp error range) (J) Transient temperature error if static temp error if 21 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Dynamic Characteristics Dynamic characteristics B-K relationship diff. equation. Solution i.e. ε(t) and δ(t) response analysis. Dynamic characteristics in time domain [ε(t) response] Dynamic characteristics in frequency domain excitation response (example) Δω: bandwidth setting time 22 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Classification of Sensors (Miller-index, ) Sensor Models (examples) Sensor Groups, Signal Transmission of Sensors (Overview) Static and Dynamic Characteristics (char. uncertainties) Sensor Types and Application Examples 23 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Ex.1 - Motion Sensors LVDT displacement sensor (LVDT: Linear Variable Differential Transformer) Optoisolator 24 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Ex.2 - Strain Gauge 25 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Ex.3 Temperature Sensors RTD (Resistance Temperature Detector) R = R 0 1 + α θ θ 0 Thermistor (Therm + istor = Thermal Resistor) PTC R = R 0 e b θ θ 0 NTC R = R 0 e γ 1 θ 1 θ 0 26 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Ex.4 Accelerometer Applications Automotive (vibration, anti-lock breaking system, airbags, etc.) Aerospace (inertial navigation, smart munitions) Sports/Gaming (monitor athlete performance and injury, joystick) Personal electronics (cell phones, digital devices) Security (motion and vibration detection) Industrial (machinery health monitoring) Robotics (self-balancing) 27 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Ex.5 Light Sensors LDR (Light Dependent Resistor) Photoresistor (ie. CdS) Photodiode (pn-junctions) Phototransistor (pn-junctions) 28 gyurcsek.istvan@mik.pte.hu 2018.07.09.
App. - Active Noise Reduction 29 gyurcsek.istvan@mik.pte.hu 2018.07.09.
Questions 30 gyurcsek.istvan@mik.pte.hu 2018.07.09.