Automatic 3D monitoring and the use of network adjustment on the railway TSA Survey Conference 1
Contents • Monitoring • Automatic 3D Monitoring • 3D Monitoring on the Railway • Data Interpretation/Calculation • 3D Monitoring Evolution • Network Adjustment in Remote Systems • Case Study: RMS • Summary TSA Survey Conference 2
Monitoring 1. Define the purpose: Inform, Maintain, Control 2. Select the monitoring method: Amount, speed and accuracy of data required etc… 3 . Define and agree the reporting and actions: What happens following the data. TSA Survey Conference 3
Stage 1 ‐ Define the Purpose Inform Obtain knowledge of asset behavior Enable evaluation of severity Data for design of remediation Maintain Confirmation of status – notification of change Contingency – Interim period to repairs Control Measurement towards limit of movement/alarm Observation during temporary works Short term watch period due to sudden instability TSA Survey Conference 4
Factors Influencing Decision to Monitor New or Dormant Fault Asset Criticality Severity of Fault Level of Consequence Visibility Reinforcing Knowledge History Culpability Politics Cost TSA Survey Conference 5
Would you monitor this? TSA Survey Conference 6
Stage 2 – Select Monitoring Method Reliability (Repeatability & Accuracy) Availability Cost Access Minimal install time Robustness/Climactic conditions Simplicity of use Operate alongside site activity Security Direct Measurement Ergonomic contingent design Low power consumption Communications TSA Survey Conference 7
Practical Considerations ‐ Safety TSA Survey Conference 8
Stage 3 – Define and Agree Reporting and Actions Record Analyse Transmit Compare Store Alert & Alarm Back up Report Confirm Present Convert Repeat Validate Archive TSA Survey Conference 9
Automatic 3D Monitoring In terms of Purpose of monitoring (stage 1) can offer information to suit all types Measurement of a single point in 3 planes of direction to +/‐ 1mm Absolute and global movement Monitor a wide range of infrastructures/furniture with relative ease Mainly unobtrusive to install and can operate in hard to access area’s TSA Survey Conference 10
Automatic Systems Historically remote system were borne out of areas that were difficult to manually monitor. E.g. Tunnels, culverts, cuttings Their potential to be more cost effective than manually monitoring areas was by product as well as all the other benefits of remove monitoring. Crossrail C701 was what really brought ATS monitoring to the fore and brought its use to a much wider audience. This and other Crossrail contracts propelled the logistical use and subsequent development of 1 second instruments. TSA Survey Conference 11
Standard ATS Set Up Controls Monitoring Points ATS’s 12 TSA Survey Conference
3D Monitoring on the Railway Slope Surface Monitoring Retaining Walls Bridge Structures Buildings Platforms Tunnel Clearance Track 13 TSA Survey Conference
Track Monitoring • Cant & Twist • Lateral Slew • Gauging • Settlement & Heave 14 TSA Survey Conference
Data Interpretations/Calculations Rotation Longitudinal profiles Convergence Vectors Relative Movement Absolute Movement Cant, Twist & Gauging Daily Averaging TSA Survey Conference 15
Alarm Management • Email • Texts • Alarm Logs • Event Logs Alarm management tools • Within a range or shot again • Mode • 3 Tap Rule • Daily Average Alarms TSA Survey Conference 16
Evolution of Remote 3D Monitoring • Robustness: Higher IP ratings • Speed of Readings • Camera’s on Instruments • Power consumption to be run • Communication improvements TSA Survey Conference 17
Introduction of Network Adjustment into remote systems Allows you to control and manage the position of your monitoring points by modelling through least squares adjustment. The adjustment allows you to create a network for your survey site and correct the data once the network is solved. It reviews your whole site as one and then creates a best fit based on this. Widely used in manual systems where there is poor control set ups. Started to be used in more remote systems and was a key component to many Crossrail sites due to the environment. TSA Survey Conference 18
Network Adjustment Key items in a good network adjustment is good common points and known stable points. Network Adjustment packages can now process the data every 2 hours and can therefore replace the need to show resected data and as live data. Especially important in tunnel areas, bends, cuttings etc. Anywhere where line of sight out of the zone of influence is restricted. E.g. Cuttings, Tunnels TSA Survey Conference 19
Case Study: Royal Mint Street 7No Automatic Total Stations 750 Mini Prisms Track Monitoring Retaining Walls Tunnels Crack Monitoring TSA Survey Conference 20
Case Study: Royal Mint Street • Originally set up as standard resecting system where each instrument uses points outside of the ZoI in order to locate itself • Change in building design meant a change in monitoring method. • Common Points file run between all 7no instruments to find out which points can link the network • Allowed us to create a network, process and adjust the data on a 2 hourly data (Which was within the defined specification for the scheme) TSA Survey Conference 21
Summary Understanding the system and its restrictions is key to getting the most out of it: Optical System Outside influences Poor Mounting positions Poor initial design due to outside constraints Anomalies Instrument Failure Automated 3D monitoring is improving is robustness, reliability and communications to create a more practical system as well as a technical one. Network Adjustment is now a viable option when certain environments are encountered and areas need to be monitored. TSA Survey Conference 22
Where to next? • Remote Scanning solutions from a Total Station • Faster Database computations • Wider and improved use of adjustment packages TSA Survey Conference 23
Questions? TSA Survey Conference 24
Recommend
More recommend
