Underground » Roadway Development
This project covers the second half of the planned effort required to demonstrate autonomous navigation (self steering) of a Continuous Miner (CM) to a proof-of-concept level. This report presents the work components undertaken and the research decisions made during the project, together with results achieved against each of the project milestones.
Since many of the deliverables of the first project stage directly contributed to, and were further developed during, the extension project, this report makes reference to components of the initial project where required. The key tasks consisted of:
· Continued development of advanced navigation and localisation algorithms, optimised for the CM automation application;
· Further development of a skid-steer remotely controlled vehicle to provide a CM scale-model test platform for evaluating the project-developed navigation technologies and algorithms;
· Extensive field trials to demonstrate and evaluate the performance of the full CM self-steering capability under above-ground field realistic conditions; and
· Development of Mine-To-Plan software for remote monitoring of a self-steering CM.
These tasks, although distinct, all contribute towards the key goal of achieving a demonstrated self steering capability for a continuous miner. It was recognised that a suitable site was required both for testing the project deliverables and also as a location for demonstrating the achieved performance of the system. The disused Ebenezer mine site was identified as an ideal location, and it was there that most of the key project deliverables were demonstrated. The most important of these contributions have been:
· Comprehensive evaluation of two high-performance inertial navigation units (short-listed from the initial project results) leading to the identification of a suitable candidate for CM autonomous navigation;
· Development, evaluation and demonstration of a novel radar-based sensor for reliable and accurate velocity measurement as an important component of the navigation solution;
· Demonstration of velocity-aided inertial navigation performance to provide absolute 3D localisation of the CM during the mining process;
· Development of a stand-alone inertial system for installation on a CM to provide visual information to an operator on the instantaneous heading, pitch and roll of the CM; and
· Development of a Mine-to-Plan (MTP) software tool to demonstrate a practical user interface for remote set up and monitoring of the self steering CM.
The final project demonstration confirmed these outcomes, exceeding the required performance specification for the self-steering capability of the CM. The key results of this final trial were:
· Demonstrated system capability to load a mine plan into the CM via the MTP tool and track the system in real time;
· Autonomous navigation of a CM over a simulated two-heading mine pattern, with a total distance travelled of 2711 meters; and
· Final position error of the CM (distance between the navigation system position and the reference GPS system) after travelling the 2711 meters was 85.1 centimeters along track and 16.6 centimeters cross track, or an absolute position accuracy of 86.7 centimeters. This equates to a navigation performance of 32 cm/km.