Leapfrog are excited to post for you a series of six blogs that map our company’s progress. To start off the first blog, Carrie Beckwith, talks to Rick Fright about how Leapfrog® came about – in the beginning.
The story Rick’s telling includes engineers, mathematicians, geologists and computer science graduates, which he describes as a ‘unique blend of expertise’, many friends from the University of Canterbury in New Zealand and many still actively involved in taking the product forward. I’m marvelling at the man-hours Leapfrog’s development must have accrued and the ‘ground breaking’ that went on to create the intuitive modelling tool geologists rely on today. Our conversation is unearthing a passion and excitement for developing new technology through research.
But how did this software first come about? How did something initially from the medical industry end up being so successful in mining?
In the beginning – titanium cranioplasty
Rick takes me back to 1991 and the Medical Physics & Bioengineering department of Canterbury Hospital in Christchurch New Zealand. Rick was working on a Wellcome Trust research grant to automate the design and production of titanium plates for neurosurgeons. Rick had heard about the work of another Rick (Beatson) a mathematician from the nearby University of Canterbury’s Department of Mathematics and Statistics, who’d developed new fast 2D methods using radial basis functions. At this time, Engineering Ph.D. student Jonathan Carr also became involved and the three set about solving the cranioplasty problem. Together they produced mathematics and software to interpolate the shape of the skull across the void of the missing area. This is basically the same way Leapfrog models topographies today.
Says Rick, “We needed to bend a piece of titanium plate into a certain shape, and naturally the best solution was the ‘thin plate spline’ kind of radial basis function – this is the smoothest i.e. least-wiggly, surface approximation to the known data.”
Jonathan Carr adds,“What we did in these early days of medical imaging is analogous to the revolution in geological modelling which Leapfrog started. Basically we moved from pseudo 3D models derived from 2D cross-sections to a full 3D system where X-ray CT and MRI data were visualised in 3D using interactive computer graphics. Surfaces were modelled with continuous mathematical functions (RBFs).”
The mathematical description provided by RBFs allowed them to build prostheses automatically from the CT data since these descriptions could be used to directly control Computer Numerical Controlled (CNC) mills and thereby manufacture precise fitting titanium plates.
Prior to the application of 3D graphics and RBFs, models for surgical planning were obtained by tedious manual tracing of contacts on X-ray images. This, of course, is a process fundamentally similar to traditional wire framing in mining.
Next –our next blog in this series looking back at the history of Leapfrog explores some of the interesting and disparate applications the technology was used for prior to mining.