Peter Rauxloh on drones
Director of Technology Solutions, Dr Peter Rauxloh, has been developing ways of applying new technologies to our work. He describes what he has been up to and how these technologies can be employed by our clients…
Q Pete, what is your role at MOLA and what projects have you been spearheading?
A It’s my job to identify and develop technologies, working practices and approaches that help us do our work more efficiently. Recently I have been developing our Small Unmanned Aircraft (SUA) capability; commonly referred to as drones.
Q Why SUA, how can it help our clients?
A Survey using SUAs has a great deal to offer those managing heritage assets at either a landscape or individual building/site level. SUAs bridge the gap between ground-based survey and expensive air-borne remote sensing. The main benefits of SUAs are that they capture 3D data at a lower cost, a higher resolution and in a shorter period than more typical survey methods. This is largely thanks to recent developments in photogrammetric software.
Q So in what areas can this technology really make an impact?
A The greatly reduced cost and ease of deployment of SUA survey compared with the traditional aerial survey, means it can be commissioned for areas and situations which would not have been previously considered. For example small sites, areas requiring a quick response due to time sensitive circumstance (e.g. intertidal zones and areas displaying seasonal crop marks) and sites that require monitoring over a period of time (e.g. coastal erosion, invasive species spread or indeed the progress of a client’s development). The capture of this data is now an accessible tool for landscape stewards.
Q What exciting results have you had so far with our fixed wing SUA?
A Whilst testing the technology the most interesting results have been the level of accuracy which can be achieved, when compared to other technologies we employ. As part of a recent survey of a late 17th and early 18th Century park landscape, valuable comparison of 3D data from a SUA survey with that produced by an air-borne laser scanner (LiDAR – Light Detection And Ranging) were possible. It was abundantly clear that for open landscapes the SUA data was more than a match in terms of detail and nuance with that derived from the more expensive LiDAR survey.
Q Do you have any advice for our clients who may be thinking about the best way to survey their sites?
A They need to consider in detail what they want from the survey. Raw survey products – like 2D ortho-mosaic maps or 3D models - can be a valuable data source from which information can be derived. For example, if a client was concerned about visibility to or from a proposed development or heritage asset then they could carry out line of site analysis of the data or generate a 'view shed' of layers, which graphically displays visible and invisible areas. Furthermore, if a client was commissioning a traditional survey of a standing building they could include a SUA survey to capture the whole building and also the spatial context in which the building exists as a whole. SUA surveys can be combined with ground or elevated photography or indeed high definition laser-scanned data creating quite remarkable and metrically accurate 2 and 3D products.I’d encourage anyone wanting archaeological interpretation of a landscape to get in touch so we can talk through the options.
