5/11/2009 1

Sensor

Transportation Informatics GroupUniversity of Klagenfurt

Transportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

Alireza Fasih, 2009

Address: L4.2.02, Lakeside Park, Haus B04, Ebene 2, Klagenfurt-Austria

5/11/2009 2

SensorTransportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

A sensor is a device that measures a physical quantity and converts it into asignal which can be read by an observer or by an instrument.

CCD Camera

Structure of Pixel for converting Photon to Electrical Signal

5/11/2009 3

SensorTransportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

A sensor is a device that measures a physical quantity and converts it into asignal which can be read by an observer or by an instrument.

PhotocellGyroscope

Flow meter2D Laser Scanner

Thermometer

Microphone

5/11/2009 4

Sensor SensitivityTransportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

Sensor sensitivity How much the sensor's output changes when the measured quantity changes

Comparing Sensitivity of Load Cell ( measuring the weight)

< 200kg

Accuracy:10gr

< 10kg

Accuracy:0.01gr

< 50kg

Accuracy:0.1gr

< 1000kg

Accuracy: 100gr

5/11/2009 5

Sensor TypeTransportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

• Thermal: – Temperature/heat sensors

• Electromagnetic: – Electrical resistance/voltage/power sensors, magnetism sensors, metal

detectors, RADAR• Mechanical:

– Acceleration, position, pressure, switch, liquid sensors• Chemical:

– Odor (smell) sensor, oxygen sensors• Optical radiation:

– Light sensors, infra-red sensor, proximity sensor• Acoustic: Sound sensors• Motion sensors:

– Radar gun, speedometer, tachometer, odometer• Orientation sensors: Gyroscope

5/11/2009 6

Features of Sensor (1)

• Light Sensors – Detecting light intensity, density, reflection, color temperature, type of light – Rich information, very low cost

• C-MOS Camera – Visual information about the environment – Processing power and storage needs are often large – Users feel uncomfortable

• Location sensor– GPS(Global Positioning System) is mostly used – Coarse location information

• Cellular network infrastructures: Global System for Mobile Communications (GSM)

6/54

Transportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

5/11/2009 7

Features of Sensor (2)

• Audio, Microphones – Interesting information: Noise level, type of input, base frequency – Using minimal processing: Less than 200 bytes of RAM – Multiple microphones: Richer information – Very cheap – Can be extended up to speech recognition by using more processing power – Ultrasonic sensors: Augment human sensory capabilities

• Accelerometers – Information on the inclination, motion, acceleration of the device – Typical: Mercury switches, angular sensors, accelerometers – Especially interesting in examination of usage patterns

• Touch sensor– Can reduce energy consumption: operative in the user's hand

7/54

Transportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

5/11/2009 8

Features of Sensor (3)• Air pressure

– Some hints: Closing door

• Temperature sensor– Most sensors are cheap and easy to use – Detect body heat, arctic or desert environments

• Passive IR sensors (Motion detector) – Movement of the device itself is detected as well

• Proximity sensors – Determine a proximate distance between a physical object in the range and the

device

• Gas sensor – Problem: delay in measurement, enormous energy consumption

8/54

Transportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

5/11/2009 9

Features of Sensor (4)• Biosensors

– User awareness – Skin resistance, blood pressure: sports and medical applications– Emotional state of the user may be obtained

• Magnetic field – Similar to a compass – Direction of a device or movement can be determined – This sensor can give false information

• Tilt sensors – Determine the tilt angles of the device

• No-power sensors – Metal ball switches, mercury switches, solar panels – Extremely low power consumption

9/54

Transportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

5/11/2009 10

Sensor Data & Processing(ETRI’06)

Input Data Sensor Data Processing Techniques

Video CCDCMOS

•Compression: MPEGX, H.26X, JPEG•Facial detection techniques•Data streamining techniques

• Data mining techniques

• Data searching techniques

• Feature extraction techniques

Audio Microphone•Compression: MPEGX, G.7XX, AAC•Audio data processing techniques•Voice recognition

PositionGPS

RF (Radio Frequency) system

•Position detection•Map data mapping (addressing)•Time detection

Bio

ECG, EEG, EMG, PPG, GSR

Skin temperatureRespiration

Blood Pressure (BP)

•Heart Rate Extraction•Stress Level•Emotion Estimation•Alpha Wave Detection•Electrohystereogram, body temperature extraction•Health Monitoring•Noninvasive BP estimation

Environment Light, Humidity, Temperature, Ultraviolet sensor

•Noise reduction•Awareness Environment

Movement•Falling detection•Gesture recognition (walking, running, ...)•Human interface

10/54

Transportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

5/11/2009 11

Sensor Fusion

Transportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

Sensor fusion is a method for conveniently integrating dataprovided by various sensors, in order to obtain the best estimatefor a dynamic system's states.

AsphaltConcrete

Environment Sound

5/11/2009 12

Sensor fusion algorithms

Transportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

• Sensor fusion is a term that covers a number of methods and algorithms, including:

– Kalman filter– Bayesian networks– Dempster-Shafer

www.xsens.com

5/11/2009 13

Level of Sensor Fusion

Transportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

• There are several categories or levels of sensor fusion that are commonly used.

Level 0 - Data Alignment Level 1 - Entity Assessment (e.g. signal/feature/object)

Tracking and object detection/recognition/identification Level 2 - Situation Assessment Level 3 - Impact Assessment Level 4 - Process Refinement (i.e. sensor management)

Level 5 - User Refinement

Fusion of RADAR and HDR Camera

5/11/2009 14

Sensor Kit

Transportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

5/11/2009 15

Data Acquisition

Transportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

• Data acquisition is the sampling of the real world values to generate data that can be manipulated by a computer. Sometimes abbreviated DAQ or DAS, data acquisition typically involves acquisition of signals andwaveforms and processing the signals to obtain desired information.

Sensor

DAQ Hardware DAQ Software

Analog

Data

Command

Log FileControllerSYSTEM

5/11/2009 16

Data Acquisition

Transportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

DAQ Board Characteristics:

Number of Digital IO lineNumber of Analog Input LineNumber of Analog Output LineSampling RateDAC Precision (10bit, 16bit, …)Internal Counter (32bit, 64bit,…)Interface Technology (RS232,USB, PCI, PCI Express, PCMCIA…)Software and Driver Compatibility (SDK, …)

5/11/2009 17

MATLAB and DAQ

Transportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

Data Acquisition Toolbox

Data Acquisition Toolbox provides a complete set of tools for analog input,analog output, and digital I/O from a variety of PC-compatible data acquisitionhardware. The toolbox lets you configure your external hardware devices, readdata into MATLAB and Simulink for immediate analysis, and send out data.

5/11/2009 18

Application in Vehicles

Transportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

Smart Car

5/11/2009 19

Next SessionTransportation Informatics Group, ALPEN-ADRIA University of Klagenfurt

• Application of Sensors in ADAS (Advanced Driver Assistance Systems)

• Accelerometer• Gyroscope• Compass Sensor• Inertial Navigation• LIDAR• 2D Laser Scanner• HDR Camera• Night Vision Camera

5/11/2009 20

Thank you for your attention

Transportation Informatics Group, ALPEN-ADRIA University of Klagenfurt