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ECE5320 Mechatronics Assignment#01: Literature Survey on Sensors and Actuators Topic: Mesh Sensor/Compressor

ECE5320 Mechatronics Assignment#01: Literature Survey on Sensors and Actuators Topic: Mesh Sensor/Compressor. Prepared by: Varsha Bhambhani Dept. of Electrical and Computer Engineering Utah State University E: ; T: ( 435)797-; F: (435)797-3054 (ECE Dept.). 3/10/2006.

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ECE5320 Mechatronics Assignment#01: Literature Survey on Sensors and Actuators Topic: Mesh Sensor/Compressor

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  1. ECE5320 MechatronicsAssignment#01: Literature Survey on Sensors and Actuators Topic: Mesh Sensor/Compressor Prepared by: Varsha Bhambhani Dept. of Electrical and Computer Engineering Utah State University E: ; T: (435)797-; F: (435)797-3054 (ECE Dept.) 3/10/2006

  2. Sensor:- Reference list • www.automatedbuildings.com/news/jun04/articles/sensicast/Sereiko.htm • www.bb-elec.com/wireless_mesh_networks.asp • www.sensicast.com/uploadedFiles/Automated_Building_Wirless.pdf • www.arcweb.com/txtlstvw.aspx?LstID=7f8fe29b-cf3d-4c89-aa30-accc75131fde • Mega-Mesh Sensor Network Design by Andrew Blanchard, Jeffry Golden,Robert Morgan,James Cai. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  3. Sensor:- Reference list • wireless.industrial-networking.com/articles/articledisplay.asp?id=1092 • mobilemesh.corante.com/archives/2004/07/07/more_on_mesh_sensor_networks.php • www.dailywireless.com/dictionary/mesh-sensor/ • www.wsnupdate.com/ • ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=1293834 ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  4. Sensor:- Reference list • Mesh Sensor Networks for Health Care Applications by Scott A. Miller • Adapting AODV for IEEE 802.15.4 Mesh Sensor Networks: Theoretical Discussion and Performance Evaluation in a Real Environment by C. Gomez, P. Salvatella, O. Alonso, J. Paradells • Hybrid Sensor and Mesh Networks by gaurav sharma et all • www.crossbow.com. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  5. Major applications • Energy/ Cost Saving:-Electric motor energy consumption is 23% of US energy consumption and 62% of industrial energy use. WSN wirelessly monitor motor operating core temperature. • Managing difficult building climates, monitoring indoor air quality:-(based on Self-healing, self-forming, battery-operable properties) – ex. Minimizing mold growth responsible for children asthma during summer when schools are vacant and systems are turned down. • Perimeter Security/ Homeland Security:- Estimate number of persons ( sensing CO2 presence), supports dry contact sensors, glass break sensor etc. Also smart smoke detectors guide fire-fighters. For ex. Sensor network at MacDill Air force Base is used to detect, classify and track soldiers and vehicles in difficult to monitor open spaces ( desert battlefield ) • Remote control :- A source node can wirelessly trigger relays and/or display or control remote devices whereas sink can transmit calibration command to sensors. • Industrial monitoring:-allows measuring of manufacturing properties for ex. monitoring of motor vibrationand temperature measurement to see if machine is running optimally. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  6. Major Applications 6.Refrigeration monitoring • Preventive Maintenance:-At Intel;s semiconductor lab, sensors are networked to track vibrations from various pieces of equipment to determine if machine is about to fail. • Wireless Theme Park:-Objectives are monitoring quality of water in tanks, to provide internet access to park visitors, improve park management, keep track of attendance at park. • Irrigation and Fertilizer Management:-Sensor networks in Oregon vineyard guides irrigation and planting, increasing crop yield. In treetops of UC botanical garden’s Mather Redwood Grove, sample environmental data help understand massive plant physiology. • Earthquake Prediction:-On Sand Andreas fault, sensor network equipped with seismometers calculate depth of fault and locate accumulating stress ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  7. Major Applications • understanding nature:- Robust sensor net on Great Duck Island off the coast of Maine aids biologist in study of leach’s storm petrels, a species of sea-bird that have mysteriosly selected this locate as breeding ground. • High speed mobile video applications on board public transport or real time racing car telemetry. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  8. Basic working principle illustrated • A “network” in which every node is equipped with a sensor and every node is directly connected to more than one other node. The sensor in every node is connected to a radio transceiver, a micro controller and a battery. This network is used to monitor environmental conditions, surveillance, healthcare and inventory tracking amongst others. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  9. Basic working principle illustrated • Mesh networking implemented over wireless LAN. • Meshis a wireless co-operative communication infrastructure between a massive amount of individual wireless transceivers. • infrastructure is decentralized (with no central service provider), relatively inexpensive, and very reliable and resilient, as each node need only transmit as far as next node. • Nodes act as repeater to transmit data from nearby nodes to peers that are too far away to reach. • Extra capacity can be installed by simply adding more nodes. • Mesh networks may involve either fixed or mobile devices. • Principal:-Dynamic routing capabilitiesincluded in each device,data hops from node to nodein real time. • Radio technology:-With mesh technology and adaptive radio, devices in a mesh network will only connect with other devices that are in a set range. Advantage is that if number of hops in the average communication path is kept low then with more devices, more bandwidth become available. • Common Architecture:-multiple fixed base station with “cut-through” high bandwidth terrestrial links that provide gateways to services, wired parts of internet and other fixed base stations. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  10. Basic working principle illustratedWireless Access Point Radio Networking Technology used in Mesh Sensors ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  11. Tiny OS:-Operating System used in mesh sensor • At basic level, TinyOS is a scheduler that manages activities of its various modular components. • TinyOS motes are programmed to pass their data bucket brigade style from node to node. This multi-hop approach keeps radio’s power requirement to minimum. • TinyOS enables the motes to process some data locally and only communicate the results of processing when an interesting event occurs. This saves processing at every node and reduces complexity and computation cost. • TinyOS is an excellent multi-tasker. It juggles streams of data flowing in from sensors and networks and plays traffic cop, directing transmission of data to other nodes. • TinyOS is only few Kilobytes in size, saves memory space on small chips. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  12. Tiny DB – A query processing system used in mesh sensor • It is a data base model on top of sensor system. • Even in completely homogenous network, underutilized nodes are good places to cache data to handle complex group queries. • Step wise procedure for query processing:- • User pose a simple query in SQL, a common data base language. • Through GUI, software describes what sensor readings are available. Meanwhile TinyDB’s declarative query language enables the user to describe desired data. • Query is sent to TinyDB Query Processor pre-installed on each mote. • Once a query is executed, TinyDB automatically extracts the data from network and dumps into traditional data base. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  13. Protocols:- SNP,MBRP, Zigbee, AODV, NST-AODV • Routing algorithms are classified into • Flat-based routing algorithm • Hierarchical –based routing algorithm • Self Configuration routing algorithm. Flat-based routing algorithm • types:- SPIN , DC, RR, MCFA. • Sensor Protocols for Information via Negotiation (SPIN) :- Each sensor disseminates its data to all other sensors in the network by assuming them as potential BS nodes • Data Centric (DC) routing algorithm named Directed Diffusion: - In this, all data gathered by sensors have an attribute value. It’s a query driven routing algorithm in which by disseminating the interest towards specific region through intermediate sensors, each intermediate sensor makes a gradient towards the sink node for data retrieving. • Rumor Routing (RR) :- It is directed diffusion suitable for networks in which geographic routing is not feasible. • Minimum cost forwarding Algorithm (MCFA):-In this, direction of determination is always known, each sensor takes a unique ID and makes routing table. After system initialization phase, each sensor takes a cost towards BS node. So message is transferred between source and sink in minimum cost. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  14. Protocols:-SNP,MBRP, Zigbee, AODV, NST-AODV contd. Hierarchal- based routing algorithm Examples are LEACH, PEGASIS and Virtual Grid Architectural Routing. Self-configuration routing algorithm This protocol classifies sensor network based on configuration of network. Some of the important existing protocols in use are described below: • Mesh Based Routing Protocol (MBRP):-Improves scalability, fault-tolerance, network life-time and deploys analogous low cost sensors. This involves:- A) Forming mesh topology System initialization takes place in three steps:- A) Selecting base nodes for zoning. B) Making zones. C) ID assignment in each node. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  15. Selecting base nodes: - positions of two set up sensors BSX and BSY are determined. first node is located at the end of the largest diameter and in the boundary of the area and the second node is located on the boundary of the other orthogonal diameter of the region. Making zones: -steps are as: each sensor in network initializes its x and y dimensions to infinity. SX at position BSX disseminates message in radiation radius R which contains counter initialized to 0. Each sensor receiving this message sets its x value to zero ,increases the counter value by one, waits λ seconds to ensure all other sensors located at the Radio-range of BS x have received the same message. After delay of λ , sensors in region 0 in x dimension disseminate new message with counter value 1 to form region 1 sensors. Procedure continues to cover all sensors and zones are formed. PROBLEM:-edge regions between Sx and Sy nodes may not be a rectangular shape SOLUTION:-distance between BSx and BSy can be chosen as a multiple of R . Protocols:-SNP,MBRP, Zigbee, AODV, NST-AODV contd. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  16. Protocols:- SNP,MBRP, Zigbee, AODV, NST-AODV contd. ID assignment:-Each node makes several links with adjacent nodes, assuming there are some Virtual channels between two adjacent nodes. Problem:- Assigning identical ID to sensors as size of WSN increases. Solution:- In 3rd phase, each sensor in the region (X,Y) generates a random number and broadcasts it for all other sensors located in its own region. Two sensors with same ID select another non selected ID randomly, broadcast it to the other sensors. The final random number assigned to each sensor will be its unique ID. Thus each sensor has region co-ordinate and a unique ID. Problem :- determine geographic location of each sensor. Solution:- Each receiver sensor can calculate its distance from the transmitter sensor by using signal strength calculation. if the physical location of the transmitter is known by the receiver, geographic location can be determined. Approximated geographical location of the Mesh nodes, can be calculated based on the characteristics and shape of the area that WSN uses and the radio-range of the sensors. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  17. Protocols:- SNP,MBRP, Zigbee, AODV, NST-AODV contd. Sensor density requirement and GoL Problem:- To find minimum density requirement for network. Solution:- When one region is formed in phase two of the system initialization (region 1), the outer edge sensors of this region contribute in constructing the outer edge of the next region (region 2). • Every sensor disseminates a message in its Radio-range Due to its circular radius shape, the boundary of the region 2 is not a circular line and has the maximum distance error ξ. • The maximum tolerable error ξ can determine the maximum linear distance between edge sensors => • to have a small error ξ , the distance between any two sensors must be less than R • Also minimum number of sensors in a network is inversely proportional to square of radio-range and directly proportional to area of region ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  18. Protocols:- SNP,MBRP, Zigbee, AODV, NST-AODV contd. • Group of leaders (GoL) :- Sensors in middle of each region have easier accessibility to neighboring regions. To use these sensors more than other sensors in order to increasing the fault-tolerance of the network, a Group of Leaders (GoL) are constructed. Sensors which receive messages between threshold values T1 and T2 ( depending upon density of network ) in phase 2 are called GoL. C) Basic concepts and routing algorithm Communication messages used by MBR sensors are as RAP ( Reserve a path) :- when a sensor is reserved and wants to form the rest of the path towards the sink node, it sends RAP to sensor in target (X,Y) region. ACK:- After receiving the RAP message by each sensor, it generates a priority number and returns it to the RAP generator sensor, by replying an ACK message. SAP:- Selects a sensor by previously selected sensor in the path among those who reply by ACK. DATA:- Contains actual data. Clear the reserved path (CRP) :- Releases the reserved path after transmitting data from source to sink. Routing algorithm can be event based or query based. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  19. Protocols:- SNP,MBRP, Zigbee, AODV, NST-AODV contd. Query based routing algorithm • Sink node knows position of region that should query about it. • Path is reserved towards the sink node by RAP. • Sink Sensors generate the priority number after receiving RAP. The GoL sensors and the sensors with higher energy resources have the higher priority to balance the energy level of nodes and lengthen the lifetime of the network. • Sink sensor returns back priority number to source node by ACK. • First source node selects a higher priority second source node and sends SAP message to it. Second finds a higher priority third source node. Finally data is transmitted from source to sink node. • After data transmission, by CRP, reserved path is released. • Sometimes to conserve energy, source node generates highest priority number. Event based routing algorithm • If the event sensing sensor knows position of BS node, it reserves a path by RAP. • Otherwise, it broadcasts a message containing meta-data about the occurred event and the position it has taken place. • After receiving the broadcast message by the sink node, the rest of the work is similar to that in the query-based routing ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  20. Protocols:- SNP,MBRP, Zigbee, AODV, NST-AODV contd. PROBLEM:- In MBR algorithm, sensors located in middle of network consume more energy as they have more communication. Fault rate increases. Solution:- when a minimum path towards the destination can not be found, path is redirected to outer region of the network which has more energy than the middle region. Simulations show that fault rate is much reduced by above methodology. PLUS POINTS:- • Directed path – omits extra communication, lengthens life-time of WSN • Shorter local ID – provides more scalability for sensors • Fault-tolerant – tries to balance energy level of sensors within network. • Increasing radio-range greatly reduces the density of the network and consequently the network charges can be reduced accordingly. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  21. Protocols:- SNP,MBRP, Zigbee, AODV, NST-AODV contd. SensiNet networking Protocol (SNP) • Most robust. • Leverages frequency diversity to ensure reliable point-point connection. • Offers self-configuring, self-healing, bi-directionality and multi-hop capabilities. • At 900Mhz , SensiNet uses slow frequency hopping spread spectrum (FHSS) modulation and transmits and receives on only clearest channels in band. • At 2.4GHz, supports IEEE 802.15.4 radios Distributed Frequency Spread Spectrum (DFSS) modulation. • PLUS POINTS- a) Less interference b) Permit higher effective throughput as each routing node can operate on unique bands simultaneously. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  22. Protocols:- SNP,MBRP, Zigbee, AODV, NST-AODV contd. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  23. Protocols:- SNP,MBRP, Zigbee, AODV, NST-AODV contd. Local connectivity maintenance mechanism:- connectivity mechanism is a very relevant elements of a routing protocol for a dynamic environment, specially in LoWPANs. It impacts :- • Route change latency:-total delay between the instant of a link failure in an active path and the moment in which an alternative route starts being used, if such a route exists. RD latency is total time needed for route discovery procedure. LLN failure detection is better than Hello message failure detection. T detect is 1.5 sec in hello message whereas it is few msec in LLN. • Route change losses (RC) :-Amount of lost packets during route change period. If nodes use LLN, RC losses can be reduced depending on implementation criteria, even to 0, packets that trigger link failure detection, as well as subsequent ones, can be buffered and sent once an alternative route has been found. Packet inter-arrival times, buffer size and RD latency determine packet loss probability. NST-AODV is the only implementation/proposal that currently benefits from this approach, while LOAD considers it as an optional feature 3) Bandwidth and power consumption:-In LLN, no control messages are sent along communication path saving bandwidth and device power resources. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  24. Protocols:- SNP,MBRP, Zigbee, AODV, NST-AODV contd. ReRR messages • Eliminating RERR messages reduces implementation complexity at the expense of introducing and/or relying on alternative mechanisms for notifying a sender that a link failure has occurred in an active path. • all reduced AODV proposals and/or implementations remove precursor lists, avoiding the related storage and functionality required C) Local Repair • In local repair a queue has to be managed and memory storage is required to buffer data packets, but this improves throughput , end-end latency, specially in large networks as routes are prepared quickly and fewer data packets are dropped. D) RREP generation • No use of sequence numbers results in reduced implementation complexity and header sizes, while keeping loop-freedom. E) Routing metric • Hop count metric chooses arbitrarily among the different paths of the same minimum length, ignoring effects such as interference or link losses, thus not necessarily finding the best routes. • The addition and evaluation of link quality metrics to NST-AODV remains as future work. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  25. Protocols:- SNP,MBRP, Zigbee, AODV, NST-AODV contd X10- key factors- availability and simplicity. • X10 transmissions are synchronized to zero crossing point of AC power line. Binary 1 is represented by 1 ms burst of 120 KHz at zero cross point and a zero point by absence of 120 KHz. • Network consists of transmission units, receiver units and bi-directional units that can both receive and transmit X10 commands • Drawbacks are slow speed, low reliability, lack of security. Effective data transfer rate is 60 bps and there is heavy signal degradation in power line. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  26. Protocols:- SNP,MBRP, Zigbee, AODV, NST-AODV contd) Zigbee – Standard wireless home networking • HAN protocol:- Software layer based on IEEE 802.15.4 standard. Doesn't need line of sight communication, single remote can command many devices. • Layered structure:- First 2 layers, physical (PHY) and media access ( MAC) defined by IEEE 802.15.4 standard. Layers above are defined by Zigbee Alliance. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  27. Protocols:- SNP,MBRP, Zigbee, AODV, NST-AODV contd) ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  28. Protocols:- SNP,MBRP, Zigbee, AODV, NST-AODV contd)Zigbee • Operate in unlicensed bands:- 2.4GHz (global), 902-928 MHz (Americas), 868 MHz (Europe) raw data throughput rates of 250 Kbps achieved at 2.4GHz (16 channels), 40 kbps at 915 MHz (10 channels) and 20 kbps at 868 MHz ( 1 channel). • Transmission distance range:- 10-75 m depending on power output and environmental characteristics . • Modulation:- like Wi-Fi, Zigbee uses DSSS in 2.4 GHz band, with offset quadrature phase-shift keying modulation. Channel width is 2MHz band with 5 MHz channel spacing. The 868 and 900 MHz bands also use DSSS but with binary phase shift keying modulation. • Frame structure:- 4 basic types data, ACK, MAC command, beacon. • Data frames:- provides payload of upto 104 bytes. Frame check sequence ensures that packets are received without errors. • MAC command frame:-for remote control and configuration of client nodes. A centralized network manager uses MAC to configure individual client’s end frame, no matter how large the network. • Beacon frame:- it wakes up client devices which listen to their address information and go back to sleep if they don’t receive it. Beacons are important for mesh and cluster tree network to keep all the nodes synchronized without requires those nodes to consume precious battery energy by listening for long periods of time. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  29. Protocols:- SNP,MBRP, Zigbee, AODV, NST-AODV contd) ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  30. Protocols:- SNP,MBRP, Zigbee, AODV, NST-AODV contd) • Channel access and addressing:-for non-beacon network, ALOHA CSMA-CA (carrier sense medium access with collision avoidance ) is used. Device addresses employ 64 bit IEEE and optional 16 bit short addressing. MAC address field contains source and destination address information. Dual address information is used in mesh networks to prevent single point of failure within network. • Device Types:- These are classified into network-coordinator, FFD and RFD. • Network-coordinator:-maintains overall network, most sophisticated, requires most memory and computing power. • Full-function device (FFD):- supports all 802.15.4 functions, can function as network-coordinator , ideal for network-router function due to additional memory and computing power, can be used as network edge device.. • Reduced function devices (RFD):- Carries limited functionality, has lower cost and complexity. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  31. A typical sample configuration in application (application notes)Zigbee ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  32. A typical sample configuration in application contd. • Zigbee is small as compared to other wireless data standards • Memory:-4 kb memory – network edge devices with limited capabilities, 32 kb memory – full implementation of protocol stack, RAM – Network-coordinator for node device data base, transaction and pairing tables. • 802.15.4 standard defines 26 primitives for PHY and MAC layers which are much lesss than 131 primitives defined for bluetooth. Benefit of above points:- Zigbee can run on simple 8 bit micro-controller such as HC08 or 8051 based processor core. • Routing algorithms use request response protocol to eliminate sub-optimal routing. • Network size can reach 264 nodes. • Security:- • Access control – maintains list of trusted devices within network • Data encryption – uses symmetric key 128 bit advanced encryption standard • Frame integrity – protect data from being modified without cryptographic keys. • Sequential freshness- to reject data frames that have been replayed. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  33. Zigbee network model ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  34. Zigbee network model Star network • Rely on central base station that communicate directly to sensor nodes. • Linear routes:- each node has one possible communication path. • Failure of individual link means information is lost. • Installation of sensor network requires sophisticated site survey and link level configuration. Each node must be positioned correctly and each point-point link tuned for maximum reliability. Star Mesh • Redundant routing at the core and star routing at edge typically with line powered routing nodes and battery powered nodes. • While an edge node may transmit to one of many routers, it is still point-point link that must be tuned. • More redundant then star but do not allow true end-end redundancy. Still installation challenge Mesh networks • All nodes can function as routers Dust networks • Smart mesh family of embedded wireless products based on full Mesh topology, utilize TSMP ( time synchronized mesh protocol) to deliver unprecedented reliability, ultra low power and ease of installation. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  35. Easy installation:- Self forming, self healing and multi-hop nature of mesh sensor network makes installation easy. Scalability/ cost effectiveness:- minimum configuration requirement is 1 bridge node+ 1 star node + software. Battery operable:- Ideally each mote should be able to survive on its own for at least a year on a pair of AA batteries. Event driven processing:- Motes become active only when an event occurs, lest they are in “sleep” mode. This saves energy and power use Major specifications Desired Characteristics of Mesh sensor ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  36. Major specifications Desired Characteristics of Mesh sensor • Self forming:- A node automatically enters network when powered on. This provides flexibility and enables quick simple deployment. • Self healing:- If a node leaves a network, remaining nodes automatically reroute, this enables robust and reliable communication path. • Multi-hop routing:- A node can communicate to a far node through multi-hop communication, hence scalability issue is faded. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  37. Limitations • Developing WSN to be immediately used for commercial applications:- This requires radia reference designs, radio chips design, software stacks design, radio-engineering and embedded development skills. This further requires a history of installing and real sensor network applications • Scalability vs. Performance:- As network grows in size, more and more energy is consumed in transmission of message from one node to another node and also information is lost along the path due to data packet loss, hence performance degrades • Develop embedded local processing capabilities within selected nodes:- for ex. Use TinyDB a query processing system by Intel research Berkeley. It is a database model on top of sensor network. Even in completely homogenous network, underutilized nodes are good places to cache data to handle complex group queries or for similar tasks. Challenge is how to organize network to leverage those nodes? • Limited memory:- Due to energy constraints ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  38. Limitations • Low power operation:- Target is at least two orders of magnitude below operational power of traditional low power platforms. In other words how to run at low duty cycle. One possible solution is to apply MANET routing protocols for low power wireless personal area network. • System level Integration:- Efficient integration of radio components, CPU core, flash memory, SRAM memory and sensors themselves. • Battery saving: - Develop routing protocols to ensure that battery operated nodes “sleep” most of time, waking only infrequently to communicate. • Limited data storage capacity:- Typically each mote has less than 10 Kbytes of RAM and 100 Kbytes of software which is 10000 times less data storage then personal computer. • Radio wave limitations:- For ex. In Redwoods at grove near Sonoma in Northern California, data is collected from devices that are so high up that they are out of radio contact with ground and reprogramming motes is needed. Also a mote stuck to a tree trunk often cannot communicate directly to a mote on other side of tree trunk ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  39. Limitations • Programming:- How one can most efficiently and reliably program thousands of smart nodes that co-exist in a system. • Security:- Protection of mote system as it is reprogrammable from hackers. For the same reason it is risky in case of open-close door sensor system. • Non-optimality and Unreliable:- Overall system can become biased or inconsistent as some nodes die resulting in noise and corrupt data. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  40. Crossbow Products • MICAz OEM and MICA2 OEM • MICAz OEM:- IEEE 802.15.4, 2.4 GHz radio, 250 kbps data rate. • MICA2 OEM:- 869/916 MHz radio transmission for 38.4 kbps data bandwidth. • Sensor boards and Modules • MICAz:- 2.4 GHz / IEEE Zigbee 802.15.4 board used for low power , wireless sensor networks. MICAz is fully compatible with Moteworks software platform. • MICA2:-433 or 869/916 MHz multi-channel radio transceiver , 38.4 kbps DR radio. • Imote2:- PXA271 Xscale processor at 13-416 MHz. • Wireless MMX DSP CO-processor. • 256kB SRAM, 32 MB flash, 32 MB SRAM. • Integrated 802.15.4 radio. • Multi-color status indicator LED • Integrated 2.4 GHz antenna, optional external SMA connector. • USB client with on-board mini-B • Rich set of standard I/O 3x UART, 2xSPI, 12C, SD10, GPIOS • Application specific I/O – 12S, AC97, camera chip interface. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  41. Crossbow Products • TeleosB:- IEEE 802.15.4 compliant. • 250 kbps, high data rate radio. • T1 MSP 430 MCU with 10 KB RAM • Integrated onboard antenna. • Data collection and programming via USB interface. • Open source operating system • Optional integrated temperature, light and humidity sensor Server Gateway Xserve Middleware for connecting wireless sensor network to enterprise information and management system through standard XML. Message formats and network protocols in WSN communicate with IP protocols used in IT back end system or industrial sector. MIB 510 Serila gateway, base station for Wireless sensor networks, serial port programming for all MICA hardware platform, supports JTAG code debugging. MIB 520 Supports MICAz and MICA2 platforms MIB600 full TCP/IP protocol, power over Ethernet ready. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  42. Crossbow Products Stargate • Linux based single board computer for self contained access point that connects wireless Sensor network to an enterprise network without a PC or server. • Multiple interfaces including Ethernet, USB, serial are provided via 51 pin daughter card interface. • PCMCIA and compact flash slots enable additional connectivity including Wi-Fi. • SPB400 is a star gateway with 400 MHz , Intel PxA255 processor, low power consumption<500 mA, embedded lines BSP package. 51 pin expansion connector for MICAz/MICA2 motes and other peripherals. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  43. ACTUATOR -COMPRESSORS ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  44. References- Actuator • www.tweakheadz.com/compressors.htm • www.barryrudolph.com/mix/comp.html • www.gepower.com/businesses/ge_oilandgas/en/our_brands/ac_compressor.htm • www.carlylecompressor.com/ • www.globalspec.com/ • www.hartfordcompressors.com/ • www.chemicalprocessing.com/resource_centers/fluid_handling/compressors.html?SESSID=0766972 ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  45. References- Actuator • members.home.nl/w.speek/comparison.htm • www.californiacompressor.com/ • www.answers.com/topic/air-compressor-2 • wikipedia ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  46. MAJOR APPLICATIONS • in some types of jet engines to provide the air required for combustion of the engine fuel. The power to drive the combustion air compressor comes from the jet's own turbines. • In SCUBA diving, hyperbaric oxygen therapy and other life support devices to store breathing gas in a small volume such as in diving cylinder. • in turbo chargers and supercharger to increase the performance of internal combustion engine by concentrating oxygen. • in miscellaneous trivial uses such as providing compressed air for filling pneumatic tires. • in rail and heavy road transport to provide compressed air for operation of rail vehicle brakes or road vehicle brakes and various other systems. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  47. MAJOR APPLICATIONS • in storing purified or manufactured gases in a small volume, high pressure cylinders for medical, welding and other uses. • in pipeline transport of purified natural gas to move the gas from the production site to the consumer. • in refrigerators and air conditioner equipment to move heat from one place to another in refrigerant cycles . • in gas turbine systems to compress the intake combustion air . ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  48. MAJOR APPLICATIONS • in many various industrial, manufacturing and building processes to power all types of pneumatic tools. • in petroleum refineries, natural gas processing plants, petrochemical and chemical plants, and similar large industrial plants for compressing intermediate and end product gases. • as a medium for transferring energy, such as to power pneumatic equipment. • in pressurized aircraft to provide a breathable atmosphere of higher than ambient pressure. • in submarines to store air for later use as buoyancy ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  49. Introduction and Basic working principle illustrated • Gas compressor: - a mechanical device that reduces the volume of gas, resulting in manifold increase of pressure of gas. • Temperature increases due to compression. • Similar to pumps:- Firstly, both compressors and pumps, increase the pressure on a fluid. Secondly, both transport fluid through a pipe. • Similar to Turbine:- is a kind of turbo machinery. Turbine transfers energy from fluid to rotor. Compressor transfers energy from rotor to fluid. Principle:- Newton’s second law of motion and Euler’s energy equation for compressible fluids ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  50. Basic working principle contd. • According to Charle’s law, temperatue is increased when a gas is compressed. • There are relationships between temperature and pressure in a volume of gas undergoing compression:- • Isothermal:- Tempearture is constant in this process. - internal energy is removed from the system as heat at the same rate that it is added by the mechanical work of compression. - This process is favored by large heat exchanging surface, a small gas volume or a long time scale. • Adiabatic :- In this process, there is no heat transfer to and from the system. - all work is added to internal energy of thegas, resulting in increase of temperature and pressure. • Polytropic: - this process assumes that input shaft work can appear as both increased pressure and increased temperature above adiabatic and that heat may enter or leave the system. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

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