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Copyright© Intel Corporation 2000-2004 Industrial Applications for Sensor Networks Condition based monitoring pilot project Lama Nachman Lakshman Krishnamurthy Researcher Hans Mulder Intel Research and System Technology Lab Ralph Kling Mark Yarvis Jasmeet Chhabra Carl Dellar ® Copyright© Intel Corporation 2000-2004 Agenda Introduction & Problem Statement Equipment Health monitoring Pilot in Intel FAB Application requirements Current Implementation (Phase 2) MICA & iMote clusters Reliability protocol Network Configuration Power Saving Protocol Status & Next steps Key learnings Intel Research •2• Copyright© Intel Corporation 2000-2004 Fab Pre-emptive Maintenance Application at Intel Use vibration signatures to identify problems with equipment Avoid failure ~5000 Sensor points in each fab 4 years of archived data Done by sneaker net today Move to wireless sensor network Demonstrate a commercially feasible ROI for sensor and mesh network deployments Intel Research •3• Copyright© Intel Corporation 2000-2004 Problem Statement Equipment failures in live production fabs is extremely costly ($Millions) Shutdown results in opportunity loss Cost of evacuation and requalifying all the tools Possible loss of wafer lots in the pipeline Need to predict equipment failures early enough and perform preemptive maintenance during pre-scheduled down-time Monitor equipment health using vibration signatures Intel Research •4• Copyright© Intel Corporation 2000-2004 Case study (RA FAB) ~5000 sensing points already instrumented 40% permanent sensors, 60% portable sensors Vibration and RPM sensors (Wilcoxon & Honeywell) Manual data collection using handheld devices Time domain data is collected, spectrum and magnitude plots are generated Data is downloaded to Rockwell Enshare software Sensors are manually configured in DB Type, location, direction, collection frequency, etc Alarms are generated, further manual collection is performed on specific sensors Intel Research •5• Copyright© Intel Corporation 2000-2004 Case Study (RA FAB) Prevention estimates Once per month -> catch (80-85)% Once per week, and selective daily collections -> catch ~97% Manual collection method is currently used Target is once per month Headcount cost : ~$500,000 in one FAB Rockwell based solution (EnWatch) Ethernet based on-line system (~$5000) 16 channels, data collection and analysis Controlled by EnShare backend Intel Research •6• Copyright© Intel Corporation 2000-2004 Application Requirements Interface to Wilcoxon vibration sensors and Honeywell RPM sensors 0.5 Hz – 5KHz range 3000 Samples, 16 bits each Collect once per week (optional selective collection) Battery life No access to power or Ethernet at sensing locations 6 months @ 1 collection per month 4 months @ 1 collection per week Reliability MTBF : 6 months Identify bad data (especially false good data) Interface to Rockwell EnShare backend Automatic network configuration and maintenance Intel Research •7• Copyright© Intel Corporation 2000-2004 Pilot Network Architecture Fab Equipment Intranet Intranet isolation Root Node Ad Hoc Mote Network Cluster Heads Mote + Vibration Sensors Intel Research •8• Copyright© Intel Corporation 2000-2004 Solution components Ad hoc Mote network MICA based clusters Imote based clusters End to End Reliable datagram transport protocol (sensor node -> Root Node) 802.11 overlay mesh network using stargates Cluster head manages data collection and sleep/wake schedule Root Node collects the raw data, stores in EnShare format and sends it to server EnShare data base imports the raw data Intel Research •9• Copyright© Intel Corporation 2000-2004 Reliability Protocol Runs on Mica motes, iMotes and Stargates TinyOS implementation Provides VarSend, VarRecv interfaces to app layer Uses Generic Packet interface to abstract network layer Sliding window protocol Connection parameter negotiation (fragment size, window size, timeout info) Receiver sends an ACK bitmap within window Sender retransmits NACK’d fragments 3 phases Connection setup (light weight, 2 packets) Data exchange (data and NACK packets) Final ACK (2 packets) Intel Research • 10 • Copyright© Intel Corporation 2000-2004 Mote Cluster Implementation Intel Research • 11 • Copyright© Intel Corporation 2000-2004 Data Collection / Power Saving Cluster head sends a command to each sensor node to start data collection Sensor node initiates reliable transport protocol with RootNode for each connected sensor Sensor node informs cluster head when data transfer is complete Cluster repeats the process for each sensor node When all sensors have been collected, the complete cluster is put to sleep until next collection • 12 • Intel Research Copyright© Intel Corporation 2000-2004 iMote Cluster Details Intel Research • 13 • Copyright© Intel Corporation 2000-2004 Intel Mote: an enhanced wireless network research platform Intel Mote is a modular, stackable design Hardware features High platform integration level (core, radio, memory…) Main board (ARM core, SRAM, FLASH, BT radio) Low power operation Power supply board (battery, AC, solar, …) Small physical size Modular HW/SW design Sensor board(s) Low cost and volume production potential Other boards (alternate radio, debug, actuator, …) TinyOS applications TinyOS base components Network layer (multihop) Sensor board Main board Intel Mote layer Power board Firmware (BT-LLS) Backbone interconnect Hardware Intel Research • 14 • Copyright© Intel Corporation 2000-2004 Network Configuration Automatic scatternet formation algorithm Forms a tree structure Clusterhead is the root of the tree (Master Role) Intermediate nodes have dual Master/Slave roles Leaf nodes are slave only nodes Free nodes alternate between BT Inquiry & scan modes to discover other nodes Free nodes can join at different levels in the tree, depending on which node they connect to Connected nodes only scan to eliminate the possibility of creating loops Simple routing algorithm Intel Research • 15 • Copyright© Intel Corporation 2000-2004 Power Saving Protocol Leverage low power modes in Bluetooth Cluster head broadcasts a “network sleep” message down the tree. Once the message reaches a leaf node, a response is sent up the tree When a master hears a response from all its slaves, it will put all the links on hold, and propagate the response up the tree Messages can still flow through the network in between hold intervals (20 second response time per level in the tree) The cluster will broadcast a “network wake up” message down the tree Intel Research • 16 • Copyright© Intel Corporation 2000-2004 Network Observations 1 minute to form a cluster of 16 nodes BT links are very stable once established Network formation overhead is amortized over long connection time BT link layer reliability is very effective, hence reducing the end to end NACKs Need to optimize the scatternet formation algorithm to select connections based on link quality, and reducing hop count Intel Research • 17 • Copyright© Intel Corporation 2000-2004 iMote Cluster integration iMote cluster Simple routing algorithm iMote MHOP header (src, dest, channel) TOS Message is not used MICA cluster & RootNode DSDV & flood protocols iMote cluster head translates between domains Route update messages from rootnode intercepted to get the RootNode ID Reliability protocol hdr/data is repackaged Sensor -> RooNode (iMote packet -> DSDV packet) RootNode -> Sensor (Flood -> iMote packet) Intel Research • 18 • Copyright© Intel Corporation 2000-2004 Sensor Board 18V power supply 10kHz+ 24bit A/D Programmable antialiasing filter PLD bridges SPI to UART interface Wilcoxon sensor Voltage output Intel Research Sensor voltage supply, A/D, filter • 19 • Intel Mote UART 900kb/s SRAM 64kB FLASH 512kB Copyright© Intel Corporation 2000-2004 Time domain data Intel Research • 20 • Copyright© Intel Corporation 2000-2004 Frequency domain data 80Hz reference signal Intel Research • 21 • Copyright© Intel Corporation 2000-2004 Status Phase 2 development complete Testing will begin in the JF3 chiller room with MICA & iMote clusters next week Hardware is installed CUB3 CUB3 deployment is scheduled for mid June Collecting performance and power data for platform comparison by end of June Intel Research • 22 • Copyright© Intel Corporation 2000-2004 JF3 Pilot Deployment Facilities Rooms Intel Research • 23 • Copyright© Intel Corporation 2000-2004 Next Steps Finalize phase 3 requirements Choose one Mote platform based on the phase 2 data Move to TinyDB/TASK Intel Research • 24 • Copyright© Intel Corporation 2000-2004 Key learnings (platform) Size requirements Not very sensitive Current solutions are much larger Mote size is negligible Power Consumption Sensor + A/D consume a lot (~60 mW) Can use large batteries Large RAM is very useful Adding more capabilities to the mote simplifies the sensor board design Fast I/O on the mote is useful Intel Research • 25 • Copyright© Intel Corporation 2000-2004 Key learnings (Network) Automatic configuration of the network is required Reducing hop count is key Heterogeneous networks are very useful Simple power saving protocols are sufficient (Cluster based) Matching radio bandwidth to application requirements can save power Fast network response time is needed, even if collection frequency is infrequent Polling specific sensors and adding streaming modes will be very useful Intel Research • 26 • Copyright© Intel Corporation 2000-2004 Key learnings (Network) Debug modes would be very useful Tracing network topology and data flows Performance and power monitoring Isolating bad data and recovering from failures Intel Research • 27 • Copyright© Intel Corporation 2000-2004 Key Learnings (backend) Interfacing into existing tools is extremely important Want to use Rockwell EnShare for network control/command Getting info into/out of Rockwell was very painful Easing the installation process is very desirable Automatically recognizing sensors and their location is very useful (sensor -> equipment mapping) Intel Research • 28 •