MX9 – Addressing critical health & safety implications for a complex road survey
For Gateshead based Academy Geomatics, the mobile mapping service provided by KOREC Professional Services has transformed the methods and speeds with which it can capture survey grade data on busy road networks.
Leam Lane is an ‘A’ class road running at National Speed Limit (70mph) and a part of a major route between Durham and the Tyne Tunnel on the east coast. It’s recently been the site of a major highways improvement scheme that was delivered on schedule and on budget. Further improvements are ongoing and consequently the multi- disciplinary survey practice, Academy Geomatics, was recently contracted to undertake a topographical survey of a 3.5km stretch of the carriageway.
For Academy Geomatics Director, Anthony Lawton, the project presented a number of concerns common to many road schemes. These included:
- Health and Safety – Anthony’s main concern was for the safety of his surveyors and finding a solution that would keep them remote from moving traffic was a priority.
- Complexity of the job – the survey involved flyovers, slip roads, footbridges and multiple junctions.
- Limited site access – due to the splitting of the carriageways etc.
- High traffic levels – the route was rarely quiet
- Cost to the client – a survey of this nature, using GNSS or optical instruments, would take around 20 days.
- Disruption to road users – if traditional techniques were used, the job would require lane closures and traffic management delaying road users.
As a long-standing user of Trimble technology, Anthony was aware of both the new Trimble MX9 Mobile Mapping system and KOREC Professional Services which specialises in collecting and processing high quality mobile mapping data using the MX9. The vehicle mounted system collects dense point cloud data along with 360° immersive georeferenced imagery using an industry-leading spherical camera, GNSS/INS technology and dual-head laser scanning sensors. The dual headed lasers are capable of capturing 2,000,000 points per second in a single pass providing optimum coverage and detail with a regular scan pattern both of which are fundamental to the MX9’s ability to generate the highly detailed point cloud required for Acadamy’s topgraphic survey.
Carrying out the survey
To achieve the highest absolute accuracy, KOREC recommended the use of Ground Control Points (GCP) at every 200m for this job. These GCP were established by Anthony and his team in advance of the survey using a Trimble R10 GNSS with Trimble’s VRS Now real-time correction service.
On the day of the job, KOREC initiated the MX9 system in an area of good GPS signal and checked the pre-defined route for optimum coverage. The survey was undertaken in less than half a day by a 2-person KOREC team with one driving the vehicle and the other monitoring all sensor performance and positional quality during data collection via the tablet used to manage the data acquisition process.
The survey included the full carriageway width with data captured in both directions. Back at the office, KOREC processed the data using Trimble Business Center, generated the point clouds and registered the data to the GCP before delivering the data to Academy Geomatics as a colourised, georeferenced point cloud and imagery, all within their required timeframe.
Academy then digitised the data to produce their client’s requested 3D AutoCAD plans.
Anthony Lawton concludes, “By using the MX9 we were able to complete this survey twenty times faster than if we’d used traditional methods. However, for me, by far the most important benefit is the health and safety aspects of this system keeping surveyors away from the carriageway. We were able to complete the job on time, using the most cost-effective survey method and achieve a quality and density of the data that was way beyond anything we would have been able to achieve on the ground. KOREC has proved to be a reliable partner throughout the project.”
Our thanks to Academy Geomatics Director, Anthony Lawton, for supplying the information for this case study.