This week, I was invited to a demonstration at Fort Cumberland of a new system for archaeological recording: Nikon’s iSpace for Archaeology being presented by Dr Geoff Avern of Southampton University. Based on the iSpace metrology system, this system has been tailored for use on archaeological sites by compromising on the accuracy in order to reduce the price; do not be mistaken though, being a sub-millimetric measuring system, it is more than up to the job of archaeological recording!
The main element of the system comprises a number of transmitters arrayed around the site up to 50m apart which use lasers to pinpoint sensors in 3D space. Sensors are mounted on a range of instruments for recording including a fairly traditional survey staff, a hand-held mini-staff for recording smaller features and an even smaller pen type instrument. The handheld instrument has interchangeable probes for different recording situations. There will soon be a camera mount also to enable photography to be spatially referenced, theoretically even storing the position and direction data within the exif data of each photograph (Nikon cameras already support external GPS to provide geolocation); with the accuracy of the system, this is even suitable for photogrammetric applications, greatly simplifying such work.
The transmitters can be freely placed and unlike eg Total Station setup do not need to be located or even levelled. All recording is undertaken in a local grid but it is simple enough to locate the grid in real-world coordinates by recording three or more known locations, surveyed by traditional means (eg dGPS). The system is initially calibrated by recording the survey staff; the array of sensors on the staff with known spacing allows the transmitters to work out their relative positions. Once calibrated, one or more of the recording instruments can be used. The data from the transmitters and sensors is relayed by wifi to a laptop computer which processes the data and passes the location data to the recording platform, currently an iPad/iPod touch. A byproduct of this is that there is a wifi network on-site which can be used for other purposes.
Surveying and recording is as simple as placing the probe onto the surface to be recorded and moving it along. The software can record a stream of points to digitise a feature (like stream digitising in GIS) or can capture individual points. As the system is locating the probe using the sensor arrays, there is no requirement to hold the staff vertically as with a GNSS/TS staff, the instrument can be held at any angle as long as there is line of site from the sensors to at least three of the transmitters.
Data recording currently comprises an iPad/iPod application which whilst being fully functional, also serves to demonstrate potential. I see the system being used to produce real-time spatial location directly to on-site mobile GIS and archaeological recording systems. The iSpace can become another measuring device in the armoury of the 21st century archaeologist. Hopefully Nikon will move development in that direction. Certainly, this would streamline recording in commercial archaeology projects where time is of the essence and costs need to be kept as low as possible. Efficiency will be key to justifying the not insubstantial outlay in purchasing the system (c. £80K).
Jess Ogdenhas kindly uploaded the iSpace presentation to Slideshare (see below) and I’m sure we will be seeing more of this system in the near future. For more details of the system components, follow the links to my Flickr stream to see annotated photos.