FLANDERS’ ARDVARC control system combines PLC control with Windows-based computer applications to co-ordinate control of any electric, or electric-over hydraulically controlled OEM drill rig.
During the drill cycle, the PLC has primary responsibility for control of the drill. Drilling functions are monitored at twenty-millisecond intervals, and control updates are made as ground conditions change to ensure the drill is penetrating the ground at optimal performance levels, while also ensuring the drill is not being damaged.
The drilling sequence controls these primary phases of the drill process:
- levelling – the drill is auto-levelled to within 0.1º, ensuring accurate end-of-hole positioning
- ground detection – once levelled, the drill bit is lowered to determine accurate ground elevation, which is compared with the end-of-hole designed elevation to determine how deep to drill
- hole collaring – ensures good hole quality once the drill leaves the hole
- drilling – bit parameters are monitored during drilling to ensure the drill is properly penetrating the ground, including vibration, rotary torque, hoist force on the bit, air pressure, rotary RPM, penetration rate and head position. Changes in feedback indicate changes in ground conditions, which in turn initiate control algorithms designed to deal with adverse conditions. FLANDERS has patents pending for its ground hardness profile algorithms
- quality checks – once the bit has reached the target elevation, the control system initiates a quality check that measures the hole and monitors any fall-back material as the bit is retracted
- retraction – once the hole is drilled and measured, the control system retracts the drill bit from the ground; and
- reset – the drill retracts the levelling jacks and indicates that it is ready for the propel cycle to begin. In the fully automated version, the drill starts to propel from one hole to the next.
The windows PC displays drill hole targets in the form of black cross marks on the GPS map. Once drilled, these crosses turn blue. If the mine has multiple ARDVARC systems in its fleet, a hole drilled by a different drill will be displayed as a red cross, letting the operators of every drill know which holes have and have not yet been drilled.
“This is a very important feature of the ARDVARC product,” said FLANDERS director of automation Josh Goodwin.
“This function is available regardless of the level of automation at the mine.”
In addition to hole locations, the HazTech system allows obstacles and hazards to also be displayed on the GPS map.
FLANDERS says that regardless of level of automation selected, ARDVARC collects highly reliable data in a SQL table that denotes production along with engine health.
This data is communicated in real-time via wireless Ethernet, either using the mine site’s existing infrastructure or a FLANDERS-provided wireless network, to a central server where it is immediately available for reporting.
Both current and historical data is then web-served for multiple clients to view at any time without disrupting the operators.
New data collection points are generated every six months during software updates, and include: availability, utilisation, and average fuel consumption.
ARDVARC is available in three levels of automation:
Base system: Intelli-Rig is a 100 per cent manually controlled system utilises Allen-Bradley Control Logix automation controllers to monitor digital and analogue input/output (IO) signals, collected and propagated over a drill wide DeviceNet IO network. The signals set up drill permissive conditions, enabling the drill to protect itself from component failure and operator abuse. The control system is connected to operator input mechanisms such as joysticks and pushbuttons, which, when activated, cause the Intelli Rig electro-hydraulic component controllers to actuate the hydraulic valves to control the drill.
Semi-Autonomous system: One Touch uses Intelli-Rig system hardware to completely automate the drill cycle, although the drill is propelled via manual control. Additionally, at any time the operator of the drill may control the rig manually. ARDVARC One Touch integrates fully with any GPS receivers for mine planning functionality via GPS map technology, indicating where operators should drill holes as well as target drilling depth based on elevation.
Full Auto system: Autonomous is an automated version of the ARDVARC drill control system. It uses the same hardware as One Touch and Intelli-Rig but enables operators to automatically propel the drill from one hole to the next. Autonomous also allows full automation for the drilling cycle, though the operator can manually control the drill at any time.
ARDVARC technology helps improve drill performance and keeps people safe
- Safety – by physically removing the driller from the drill, particularly when drilling near the toe or the crest, risks are reduced or even eliminated depending on the level of automation
- Utilisation – blasthole drills commonly only drill 40-60 per cent of the shift time. Utilisation increases incrementally with the level of technology. The greatest contribution of complete drill automation is increased utilisation of the equipment by enabling mine operators to drill through blast outages, shift changes and operator breaks
- Training and recruitment – if finding skilled drillers or training them is a challenge, automated drill functions can compensate for limited skills. If there is a shortage of operators in general, remote control or autonomy can help resolve the problem. Also, the built-in intelligence in the drill controls protects against inappropriate operations and helps all drillers perform at a more uniform level
- Reliability and maintenance planning – health monitoring systems provide real-time information on the operating parameters of the drill. This information can be used to detect harmful conditions, preventing damage, schedule on-demand maintenance and reducing maintenance cost, and improve preventative maintenance which leads to improved availability
- Productivity – automated or drilling assist functions increase the average production rate among all drillers. Combined with increased reliability and utilisation, the overall total productivity can be increased dramatically
- Reporting and management – by displaying drilling information directly in the cab as well as in exported reports, the driller, the operations manager, and the maintenance manager can better address real or potential problems
- Total drilling cost – the effect of increased productivity, better capital use and lower labour costs is to dramatically reduce total drilling cost. One particularly easy saving to measure is the reduced fuel cost thanks to the compressor management system
- Bench control – a combination of GPS location, auto levelling, and exact hole depth control allows for more level benches
- Fragmentation – combining improved hole straightness and location with integrated strata recognition gives the opportunity to load each hole for optimised blasting and fragmentation. This may shorten the shovel loading cycle, but primarily improves the throughput in the crushing plant or the materials handling systems.