Presentation on theme: "Its all about fun with sensors!! Amit Gaur. Outline Description of Accelerometer based sensors Bluetooth Technology and BlueSentry Data Collection from."— Presentation transcript:
Outline Description of Accelerometer based sensors Bluetooth Technology and BlueSentry Data Collection from BlueSentry Applications Research Challenges Further Work
Motivation for studying acceleration Accelerometers are used universally for the analysis of acceleration, velocity, and displacement monitor the vibration level monitor and predict the health and condition of moving machinery Applications: Game Controllers Ultra-sensitive accelerometers : in personal computing devices and handsets, eg accelerometer enable single-handed menu scrolling, map panning or web browsing without the use of a stylus or push buttons. Designers of sports and health-related devices : pedometers and calorie counters for step counting, distance traveled and speed measurements. Portable blood pressure monitoring devices to ensure proper arm positioning. Used to measure the acceleration undergone by satellites
Accelerometers Sensor to measure rate of change of velocity Mass-spring system based on Newton’s 2 nd Law & Hooke’s Law Capacitor to measure displacement http://ccrma- www.stanford.edu/CCR MA/Courses/252/sensor s/node9.html
Other types of accelerometers piezoelectric accelerometer : based on the property exhibited by certain crystals where a voltage is generated across the crystal when stressed. Gyrometers: measure angular acceleration Optical Accelerometers: use optical sensors Heat Convection based
Bluetooth Blue Teeth?? What are we talking about? Harald Blåtand – 10th Century Viking King Literal translated to “Bluetooth”
Bluetooth for the Real World short-range wireless communication technology Frequency hopping spread radio technology Wireless connection between devices changes frequency at fixed intervals of time Master slave connection model Master determines timing of hopping, selection and sequence of frequencies used.
BT Topology Master Slave Piconet ScatterNet Bluetooth Piconet and Scatternet formation Master / Slave Scatternet Piconets Ref:www.ccng.uwaterloo.ca/Seminars/Presentations/bilm. ppt
Advantages of using Bluetooth Allows tranmission range of upto 100 metres Not limited by line of sight Low power consumption Standardized protocol allowing for easy interoperability Bidirectional mode Reduces the clutter of wires and associated hazardous connections. Guarantee of data transmission by acknowledgement system.
Bluetooth Profiles Wide variety of available services Generic Access Profile Service Discovery Profile Cordless Telephony Profile Intercom Profile Serial Port Profile Headset Profile Dial-up Networking Profile For more on Profiles: http://www.swedetrack.com/usblue4.ht m Fax Profile LAN Access Profile Generic Object Exchange Profile Object Push Profile File Transfer Profile Synchronization Profile
BlueSentry™: Bluetooth™ Sensor Adapter Data Acquisition and Control Module 8 channel 16 bit AtoD converter Samples analog signals and converts to a Bluetooth enabled digital data stream
Bluetooth: Serial Port Profile defines how to set-up virtual serial ports on two devices and connecting these with Bluetooth. forms the basis of a number of other profiles, such as dial-up networking, generic object exchange, and object push Using this profile provides the Bluetooth units with an emulation of a serial cable using RS232 control signalling (RS232 is the standard protocol used in serial port communication) This profile ensures that data rates up to 128 kbit/sec.
Programming Environment Application developed on HP iPAQ with Microsoft Pocket PC 2003(OS) Developer used: Microsoft Embedded Visual C++ Sensor Data collected from BlueSentry using Serial Port Programming Data cleaning done using Perl and Python Scripts
Applications 1. Location Based Services 2. Gesture Recognition 3. Applications in Gaming
Overview of Localization Techniques Emerging mobile computing applications often need to know where things are physically located. mobile devices such as mobile robots, laptops and PDAs already use 802.11b protocol for wireless communication. The IEEE 802.11b wireless Ethernet standard has been deployed in office buildings, museums, hospitals, shopping centers and other indoor environments
Ekahau Positioning System 802.11b Wireless Positioning Engine Developed at the Univ of Helsinki Tracking algorithm based on Received Signal Strength Intensity from Wireless Access Points
Improving Localization Performance All localization services have shortcomings: 1. Access point problems: rogue access points, weak/absence of signal strength:signal strength available only in certain areas 2. Errors in accuracy due to signal fading, multipath
Navasync Experiment Accel x Accel y Accel z Wireless x Wireless y Wireless Speed
Gesture based Interaction Home appliance control with gestures
Simple Application to Gaming:Arkanoid Aim: To control paddle via accelerometer Game is played on the IPAQ Accelerometer serves as a wireless joystick
Further Work Develop online streaming application for data collection, cleaning, analysis and feedback for the following: 1. Improved localization (using data/sensor fusion techniques) 2. Online gesture recognition system 3. Controlling paddle ball using accelerometer
Work Ahead Sensor Fusion: Develop a model for interpreting input from Localization Program as well accelerometer/sound sensor. Eg. Which sensor stream is more reliable and when? Gesture recognition: Training required for gesture, same applies for the game application
Key Takeaways so far…. Familiarity with devices: Accelerometer, BlueSentry, iPAQs Working with sensor streams Sensor Fusion : Multi Sensor Data Collection And……I have miles to go before I sleep.
References http://www.palowireless.com/infotooth/ Bluetooth.org http://www.vtt.fi/ict/publications/plomp _et_ailisto_030821.pdf http://www.vtt.fi/ict/publications/plomp _et_ailisto_030821.pdf Survey and Taxonomy of Location Systems for Ubiquitous Computing: Hightower and Borrielo Miscellaneous web references