Independent Reports

At the Golden Rocks conference in 2006 a workshop was conducted to investigate the state-of-the-art in laser scanning and photogrammetric methods for rock face characterisation.

Vendors were required to demonstrate how a 3D model of a rock face could be captured using their systems during the workshop, and were required to submit an analysis of the rock face to the organisers for review in November, 2006.

ADAM Technology was the only vendor who created the 3D model of the entire rock face in real-world co-ordinates during the workshop — in fact, we did it twice, using two different lenses and two different techniques to show they delivered the same result. It took just over 10 minutes using one technique and just over 20 minutes using the other.

ADAM Technology was also the only vendor who submitted the analysis by the original deadline. The deadline was extended by three months and even then only one other vendor submitted any data at all.

The organisers evaluated the submitted data and found that when compared with 12 control points not used for orientations, ADAM's terrain model was three times more accurate on average (with the largest error being 1/5^th as large) and four times more dense, but required just 1/9^th the time to generate (90 minutes vs less than 11 minutes).

Figure 1. 3DM Analyst's terrain model.

Figure 2. Other vendor's terrain model.

Thanks to the "averaging" nature of discontinuity orientation measurements, however, where many DTM points are used and the best fit plane found, the actual joint orientations, set means, and trace lengths agreed extremely well. The organisers concluded that "the obtained results indicate that digital photogrammetry yields reliable and reproducible results when applied to rock mass characterization. Digital photogrammetry is thus a mature enough technology that can be used with confidence in the profession provided care is taken to follow the guidelines provided by the Presenters in their papers and by the authors in the introductory paper to this report."

In early 2007 Rio Tinto Iron Ore conducted a trial to compare 3DM Analyst Mine Mapping Suite with Sirovision, which they had been using for geotechnical engineering for several years.

Despite the extensive experience they already had using Sirovision, and just a couple of hours of training on 3DM Analyst, they found that "the image capture using ADAM technology is approximately 1/4 of the time taken with SIRO. Data processing (for projects) as much as 1/5–1/6 of the time as compared with existing SIRO techniques."

They also concluded: "It should also be mentioned that the ADAM user interactivity was rapidly picked up, with simple use of available tutorial information and their relatively automated systems. In comparison, the existing in-house SIRO training and competency has been recognised as not only thorough but also arduous, limiting the potential number of staff proficient with it at any one time."

Please contact ADAM Technology for a copy of this report.

In 2006 Zostrich Geotechnical published a presentation comparing digital photogrammetry using 3DM Analyst to standard geologic mapping techniques.

They found that a job requiring a total of 36 staff-hours could be completed using 3DM Analyst in just 3.5 hours. They also observed that by using the 3D view of the DTM in the software, "The engineer can safely examine the potential failure area in great detail from a multitude of angles. It is possible to literally 'fly' around and above potential rock failure blocks, even those in active failure. [...] While physical examination of the block may be required at some point, this method allows for detailed examination and analysis of the situation without the rock scaling and rope work normally required to assess the situation."

They concluded that "Digital photogrammetry, and associated rock analysis with the assocaited DTM's and images increase the efficiency, and accuracy of any rock design where large or poorly accessible areas must be mappped, great geologic detail is required, or where dangerous mapping situations exist."

In early 2005 Roche Mining conducted a trial to evaluate the suitability of 3DM Analyst Mine Mapping Suite for highwall coal seam mapping, dump profiling, and blast profile mapping.

They compared the results using a range of different cameras, from the Canon EOS 10D digital SLR down to $300 compact digital cameras, as well as a laser scanner being operated by an independent contractor.

They found that the 3DM Analyst data was within 0.3% of the values obtained using conventional surveying techniques, while the laser scanner was only within 1.2%. The author reported in private correspondence that the fieldwork for the laser scanning was 3–4 hours with two people plus 30 minutes of processing, while the fieldwork for 3DM Analyst was 2 hours for one person (capturing photographs using multiple techniques and using many more control points than usual, for testing) plus 1.5 hours of processing.

Reprocessing those same images two years later, with the latest version of the software on a current PC, takes only 20 minutes — a five-fold improvement in productivity! This is one of the big advantages of a software-based system that relies on cheap and readily-upgraded hardware over a technology that relies on expensive instruments, like laser scanning does — every year the system gets better, rather than increasingly obsolete.

In 2004 BHP Billiton-Mitsubishi Alliance (BMA) conducted a trial to compare 3DM Analyst with Sirovision for the purpose of surveying for resource model/reconciliation, highwall mapping (lithology, geology, selected horizons), and resource modelling (top/bottom of seams, horizons, faults, dykes).

Each vendor was invited onsite for a day to perform the field work and was later required to submit their data for comparison. Both teams used identical cameras (Nikon D1x's, both originally supplied by the CSIRO) and identical lenses for the main portion of the trial, allowing direct comparisons between the two packages to be made. The result is an incredibly extensive report on the outcome of this trial.

Using identical cameras and lenses the 3DM Analyst data was found to be over twice as accurate on average, with the largest error being less than 1/3^rd the largest error of Sirovision. The vertical accuracy was 3.4 times better.

The author of the report also states: "BHPB Technology has generated a large number of 3D images for BHPB Iron Ore operations during the last two to three years. Some of the recent images have been rerun with 3DM Analyst. The range of camera to image distances was 450 m to 850 m. It was found that in every case the 3DM Analyst images were significantly easier and faster to be generated and the resulting 3D images were more accurate than the Siro 3D images."

The author concludes: "The results of the field trial at Goonyella have indicated that the Adam Technology software is more accurate, faster, more flexible, easier to use, more robust and more rapidly developing, provides better quality models, has better software support and requires less training. Based on technical considerations of the trial results, Adam Technology’s 3DM Analyst plus CalibCam softwares provide the best solutions for BMA's highwall mapping."

The report also makes a number of recommendations for further enhancements, noting that "During the test period a number of recommendations were made to make the 3DM Analyst software more suitable for large mapping projects outlined in the scope of work. Adam Technology was very proactive and started working on the recommendations immediately. As a result, the software has improved significantly. Some of the remaining enhancement suggestions are listed here." ADAM is very proud of the fact that every one of the recommended enhancements were added to the software within two months of the report's release!

The download includes the original report, a PowerPoint presentation containing the figures referred to in the report, and ADAM's own report on the trial, referred to in the BMA report as "Appendix 4".