Overviewo What is a sensor?o Motion sensoro Types of motion sensorso Motion Detectiono Types of Motion Sensingo Dual sense technologyo Motion Sensor in mobileo Motion sensor in Gameso Conclusiono References5/22/20132
Sensoro A sensor is a device which receives andresponds to a signal.o A sensor (also called detector) is a converterthat measures a physical quantity and convertsit into a signal which can be read by anobserver or by an (today mostly electronic)instrument.5/22/20133
Specifications of Sensor Accuracy: error between the result of ameasurement and the true value being measured. Resolution: the smallest increment of measure thata device can make. Sensitivity: the ratio between the change in theoutput signal to a small change in input physicalsignal. Repeatability/Precision: the ability of the sensor tooutput the same value for the same input over anumber of trials.5/22/20134
Types of sensors There are many versions of each type which mayuse a different sensing principle or may bedesigned to operate within different ranges. The sensors are used to measure and/or detect ahuge variety of conditions including: temperature,pressure, level, humidity, speed, motion, distance,light or the presence/absence of an object andmany other types.5/22/20135
Motion sensors The term ‘Motion sensors’ can be used to refer to anykind of sensing system which is used to detect motion;motion of any object or motion of human beings. Motion sensor is also called as motion detector. Motion sensors are commonly used in security systemsas triggers for automatic lights or remote alarms andsimilar applications.5/22/20136
Types of Motion sensors The way in which a motion sensor workstypically depends on the type of sensor beingused, which often depends on the device thatuses the sensor.There are two basic types of motion sensors: Active Sensors Passive Sensors5/22/20137
Active sensors Active sensors emit a signal, typically an burstof (light, microwaves or sound) waves which isreflected by the surroundings. The reflected signal is received by the sensorand takes necessary action. When something moves within the area of anactive motion sensor, the change in signalthat is reflected to the sensor activates thesystem.5/22/20138
The active sensor is one of the most common andreliable sensors used in a security system. For example, when an automatic faucet senseshands underneath it, a device is signaled to runwater in the sink.5/22/20139Contd...
Passive sensor Passive sensors are a type of motionsensor that do not emit a signal, butinstead detect infrared radiation aroundthe sensor. As this sensor detects temperaturedifferences, it is well suited to detectingthe motion of people by their bodytemperature.5/22/201310
5/22/201311Use as a human detection sensor toautomaticallyturn lights on when a person is present in a roomand to turn them off when nobody is there.When a person oranimal moves throughthe area, heat from themovement is detectedby the sensor, which thenactivates the system towhich it is connectedContd...
Motion sensing is used in number ofapplications• Automated lighting system• Security systems• Smart Floodlights• Burglar Alarm• Radar Guns5/22/201312 TYPICAL APPLICATIONS
Advantages of Motionsensor Saves time Security Easy to install Saves energy Powerful transmission5/22/201313
Motion detectionMotion detection is the process of detecting achange in position of an object relative to itssurroundings or the change in the surroundingsrelative to an object.Motion can be detected by: Infrared (Passive and active sensors) Optics (video and camera systems) Radio Frequency Energy (radar, microwave motiondetection) Sound (microphones and acoustic sensors) Vibration (seismic sensors) 5/22/201314
TYPES OF MOTION SENSING Local Motion Sensing Ultrasonic Motion Sensing Microwave Motion Sensing5/22/201315
Local motion sensing Infrared light is a spectrum of non-visible — forhumans at least — light that is emitted byobjects when they produce heat. Infrared motion sensor systems are one of thecheapest and most reliable systems available. An infrared motion detector uses infraredsensing to detect motion in a given area.5/22/201316
The use of infrared technology usually allows such adetector to only pick up on heat. Infrared sensors are characterized by highsensitivity, low cost and are widely used. An infrared motion detector can also be set to onlypick up on certain levels of heat, making it possibleto ignore small animals. This type of detector is often used as part of alarger security system. 5/22/201317Contd...
Ultrasonic motion sensing Ultrasonic motion detectors use sound waves todetect motion. If movement is detected, the soundwave pattern is disrupted and alarm is signaled. It senses motion byanalyzing sound wavesin its environment. These frequencies are generally inaudible tohumans and most animals and do not pass throughmost objects. 5/22/201318
Active motion sensors generate soundwaves in the ultrasonic frequency range,typically around 30 to 50 kilohertz (kHz). When no objects are moving in the area,the pattern of sound and the time it takes tobounce back remain the same. If something moves, the detector sensesthat the level or phase of the returningsound waves has shifted slightly.5/22/201319Contd...
Microwave motion sensing Microwave motion sensor systems send outmicrowavesthat bounce off an object and back to the sensor. The sensor then readsthe frequency of thereturning waves. If an object is moving, the sensor receives differentmicrowaves than the ones it sent out, signifyingmovement and setting off the alarm.5/22/201320
These types of motion sensor systems cover alarger area than infrared sensors, they arecapable of penetrating walls. They are more reliable over longer distances. Their radiation is unhealthy for living organisms. Despite this, they are the least popular motionsensor system on the market because of theirtheir cost.5/22/201321Contd...
Dual sense technology Dual technology systems use a combination ofinfrared and microwave motion sensor systems toprovide the most complete coverage available. Using both forms of technology allows dual motionsensor systems to reduce the occurrence of falsealarms by combining the microwave technology’scoverage range and the infrared technology’s use ofheat sensing. The dual technology system is rapidly gainingpopularity among homeowners and businesses alike.5/22/201322
CELL PHONES WITH MOTIONSENSORS The motion sensor used inmobile phones is accelerometerwhich is a complex motion sensor. It translates motion into action onthe screen. Accelerometers are used in tabletcomputers and digital cameras sothat images on screens are alwaysdisplayed upright.5/22/201323
Motion sensing in Games Motion sensing technologyis an emerging technologyin Gaming. Our focus technology will be Microsoft’s Xbox360 Kinectperipheral, which is the first demonstrator of touch free motionsensing. The primary innovation of Kinect (and the most secretive) is thedevice that enables advanced posture, gesture, facial, andvoice recognition.5/22/201324
The Kinect is composed of three major hardware componWebcamAn Infrared projector and sensorMicrophoneKinect5/22/201325
Challenges faced Limited Camera And Sensor Capability Better Audio Sensing Capability Limited Body Recognition5/22/201326
ConclusionMotion sensing, though important in gaming, willultimately make its biggest impact in non-gamingapplications5/22/201327