GDSTR

Read – Design and Deployment of Industrial Sensor Networks: Experiences from a Semiconductor Plant and the North Sea. Authors: Lakshman Krishnamurthy…

http://www.cse.iitk.ac.in/users/cs725/lec_notes/industrial-sensor.html

Key points:

1. Look into “Predictive Maintenance (PDM)” ^

• Predictive maintenance (PdM) has many goals:
  • Reduction in catastrophic failures
  • Move from calendar-based maintenance to indicator-driven maintenance
  • Quantify a new system within the warranty period
  • Meet factory uptime and reliability requirements
• Paper focuses on vibration analysis. Other techniques for PdM include oil analysis, infrared thermography, ultrasonic detection.
• Goals of paper:
  • Validation of requirements for PdM
  • Effect of deployment environment on sensor network
  • Assessment of sensor node platform characteristics
  • Experience from an extended period of deployment
• The possible approaches to PdM are:
  • Online system: needs to be planned at the time of industry layout; can be expensive
  • Manual system of taking vibration readings: labour is expensive, quality of prediction may not be adequate
  • Use sensor network: cost is inbetween the above two
• 2. Site Planning

• Necessity of site planning:
  • Assess RF coverage
  • Check for any RF interference
  • Mechanics: where to place the various nodes
• Their site survey showed no RF interference, and in general good radio connectivity.
• Connectivity was better at larger frequencies; 433MHz had connectivity problems: could not penetrate some barriers.
• Note: the metal in industrial environments probably tends to improve connectivity through reflections, unlike office environments.

How: Simple Data copy application used to test interference

3. Architecture

• Uses Sleep/wakeup protocol for battery lifetime.
• Each collection period – data transfered to cluster
• At Stargate – Time Stamped & file created for sensor channel
• Stargate copies to root stargate periodically
• Transfers data via serial cable using Kermit protocol to bridge Stargate
• At Bridge Stargate – connected to Intranet & Server
• At Server – data collected and analysed

4. Issues

• Power Management
• Fault Tolerance
• Data Transfer
• Power Consumption