Satellite imagery-based change monitoring, volume estimations and real time fire detection is bound to become a popular remote site solution in the post-lockdown era.
In the post-lockdown era, the focus is expected to shift towards remote monitoring of mining and project sites. Travel bans and restrictions, social distancing and limited on-site personnel measures will be in place for the foreseeable future. Site monitoring can however not be neglected, and satellite imagery-based monitoring offers a fast and cost-effective means of updating and evaluating the site surface conditions.
Pinkmatter Solutions was established in 2002 and based in Pretoria. The company launched the FarEarth system to service the mining sector for surface change monitoring and volume estimation, utilising satellite imagery. As a technical partner with Airbus DS, Pinkmatter established the Stack Insight platform. Pinkmatter is also an authorised reseller of Airbus products in South Africa.
The main advantage of using the FarEarth platform is that it is entirely web-based, and all calculations are done on-the-fly. Only a login subscription and internet access are required, no need to install specialist software or dongles. The FarEarth platform is agnostic and can ingest imagery and metadata from a variety of sensors. It is also possible to import third party metadata into the platform.
Imagery forms the basis of remote site monitoring and range from low, medium to high resolution images that can be cropped to be site specific. It is possible to obtain both archive imagery if it available over the area of interest (AOI) or to task a satellite to obtain imagery over the AOI. The processed tasked imagery is available within 48 hours and all products can be downloaded from a secure FTP site.
Single images, collected over time as a series, forms the basis of the FarEarth Change Monitor platform. Optical images, with a range of spectral bands, can be collected and ingested into the system. The proprietary algorithms can create a range of layers or masks that visually identifies changes on surface between acquisitions. Mine site applications includes monitoring of construction or removal of infrastructure, expansion of open pit operations and related mined material movement. It is also possible to determine the presence of surface water and changes in vegetation. Utilising NDVI data, it is possible to delineate gains and losses of vegetation and construct phenology curves as part of environmental and rehabilitation projects. By incorporating artificial intelligence and machine learning, Pinkmatter has developed a ground-breaking system that is used in settlement detection (house counting) and outlining structures that is a crucial component of census inputs into social and labour plans (SLPs).
Volume estimation can be performed by photogrammetry, where stereo or tri-stereo images are acquired over the AOI. During the proof of the system in cooperation with a mine in the Northern Cape, it was found that the accuracy of the volume estimate was within 2% of the surveyed volume of the stockpiles and dumps. The same data is used to construct digital elevation models (DEM), digital surface models (DSM) and digital terrain models (DTM) used extensively in hydrological studies and placement of infrastructure. The FarEarth platform provides a quick view of the models and can be downloaded from the secure FTP.
Synthetic aperture radar (SAR) satellites are used to detect surface movement over time to produce interferometry products (InSAR). Pinkmatter has developed a proprietary algorithm for phase unwrapping that is producing high quality surface movement monitoring (SMM) products. The main application is to monitor the formation of sinkholes in karst landscapes and mining induced subsidence that poses a risk to surface infrastructure and communities. InSAR is also used in monitoring the stability of dam walls and tailing storage facilities (TSF) and can be used as an early warning for potential failure. Areas that have persistent cloud cover, such as the tropics, have very small windows of opportunity for optical image collection. As SAR is not affected by cloud cover and can obtain acquisitions during the night, it is used as an effective alternative to construct DEM, DSM and DTM for these regions.
Pinkmatter Solutions also developed the FarEarth FireBox system, which offers near real time fire detection, a service that is unique. As the imagery from the satellite pass is processed in near real time, the FireBox algorithm detects fires and generates and alert. The alert is sent to emergency response teams by SMS and followed by an e-mail that contains the GPS coordinates, a cut-out of the detected fire image and a kmz attachment. The system is also used for fire scar monitoring and the archive is utilised to study and evaluate historic fire events.
Pinkmatter Solutions is also closely involved in the ground receiving station sector. The FarEarth System has been developed for ground stations to assist with tasks ranging from image processing from raw images to value-added products, an image catalogue and archive to the development of the innovative Geoportal. The system has also been developed for antenna controls to assist with acquisition control and monitoring. Recorded satellite passes from several different satellite sensors can be viewed on the FarEarth Global Observer website for free. Pinkmatter Solutions is also intimately involved in the small satellite and cube satellite sector and was a partner in the nSight small satellite project. Pinkmatter is also moving ahead in establishing an antenna hosting service at their site office, east of Pretoria.
Satellite imagery based remote site monitoring offers an ideal solution to the post-lockdown mining sector. It limits risks of on-site work and number of staff required to be active and reduces travel. FarEarth brings the mine site or project to the boardroom or remote worker at home or the office. The FarEarth platform is an established and proven system that offers high quality products to their clients, with a quick turn-around time and competitive pricing.