1. TeleRemote Control - It Comes of Age
Thomson Technology Ltd.
260 Fielding Rd., Lively, (Sudbury) Ontario Canada P3Y 1L6
DECEMBER 3, 1997
Proprietary Notice
This document contains information proprietary to Thomson Technology Ltd..
Disclosure of this documentation to third parties without the prior written permission of the President of
Thomson Technology Ltd., is expressly prohibited.
TtechThomson Technology Ltd.
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Abstract
Line-of-sight radio control has received widespread acceptance for use in
many mining methods because today’s technology offers improved
economics and personnel safety. Significant advances in higher au-
tonomy for mining machines are not currently seeing widespread use
even though they offer great future potential. With autonomous capabili-
ties being a longer-term goal, a logical sequence of advances based on
TeleRemote control is proposed. Under TeleRemote control, the operator
is in direct control of the machine at all times. Three levels of TeleRemote
control systems are presented including line-of-sight, extended line-of-
sight, and full load-haul-dump applications. Distributed control and
sensing subsystems arranged in a vehicle control area network support
incremental system expansion through the three levels of TeleRemote
control and prepare the machine for integration of higher levels of
automation as mature technology becomes available. This approach
allows full exploitation of today’s mining automation technology with a
flexible future growth path.
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Table of Contents
1. INTRODUCTION ....................................................................................... 4
2. TELEREMOTE SYSTEM ADVANCES ................................................... 6
3. TELEREMOTE CONTROL SYSTEMS .................................................. 7
3.1 MACHINE MECHATRONICS ............................................................................... 7
3.2 COMMUNICATIONS SYSTEMS ............................................................................ 13
3.3 HUMAN MACHINE INTERFACE .......................................................................... 14
4. CONCLUSIONS .......................................................................................... 15
5. REFERENCES ............................................................................................ 16
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Introduction
The use of remote control systems for mining machines is gaining momentum rapidly as the technology
becomes more capable. This increased capability is a logical development spurred on by the demand of mine
operators to improve methods for bulk extraction and ore recovery, and to increase utilization of mining
machines. Radio controlled loading, introduced in the mid-seventies for Load Haul Dump (LHD) machines,
enabled mines to refine existing mining methods and introduce new methods with improved safety and
economics. Examples include:
• Longhole Stoping – improved ore recovery with remote controlled LHDs from standard drawpoints with
reduced risk to personnel;
• Vertical Retreat Mining — with minimal drawpoints in narrower ore bodies up to 10 m wide, the application
of remote control avoids drifting in waste to establish drawpoints while recovering more of the ore;
• Vertical Retreat Pillar Recovery – recovery of ore remnants abutting backfilled stopes.
Figure 1 illustrates the general mucking process and the need for remote control of the LHD for operation in
the stope. The operator controls the loading process from a safe point in the drift using radio controlled
loading.
Figure 1: Mining methods, such as vertical crater retreat, are conducted more efficiently
and safely with the LHD operating under TeleRemote line-of-sight control in the stope areas.
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Remote control technology used in these examples provides a Line-of-Sight (LOS) radio link between the
operator and the LHD. The operator is present at the mucking zone to directly observe and control the LHD,
but is removed from hazardous areas. The maximum safe distance an LHD can be operated line-of-sight is
about 200 meters. At this and greater distances the operator cannot clearly see the action of the machine.
Typical use of 450 MHz in radio control equipment does not travel reliably around sharp corners. These
restrictions combine to result in limited efficiency and ore recovery, and limit the applications of LOS radio
control. After loading, the operator assumes manual control to tram the unit to the dump point. This transfer
cycle from radio to manual control and back again causes a loss of time in the mucking cycle and affects the
productivity of the LHD. However, these mining methods are only possible because of the application of LOS
radio controls and provide a significant return on investment. Today, LOS remote control technology is widely
accepted, not only for use on LHDs, but for other mining equipment including locomotives, rockbreakers,
drills, bolters, etc.
The success of LOS radio control naturally sparks visions of fully autonomous machines with reduced need
for underground personnel. Fully autonomous operation, however, requires a large investment in technology
and a dedicated mine plan. Several R&D initiatives have demonstrated autonomous tramming , but these
systems typically require added infrastructure for light tracks or guide wires (Vagenas, 1996). Multiple ma-
chine operation by a single operator also requires a guidance infrastructure to allow machines to operate
autonomously while tramming. This technology is not widely accepted at this time, however, it holds great
future promise depending on further R&D initiatives, support, and demonstrated success.
This paper outlines recent advances in TeleRemote control systems for mining equipment. With autonomous
capabilities being a longer-term goal, we present a logical sequence of advances for radio control technology
to extend the operating range of the remotely controlled machine to go around corners and travel greater
distances. TeleRemote control places the operator in direct control of the machine in remote operations
thereby eliminating the need for an autonomous mode. TeleRemote LOS control refers to the limited LOS
radio control capability discussed above, where the operator directly observes and controls the LHD, but is
removed from hazardous areas. An improved capability level, which we refer to as TeleRemote Extended
Line-of-Sight (ELOS), still requires that the operator be present near the mucking zone, but provides more
advanced control and operator feedback to overcome some of the limitations of LOS control. TeleRemote
ELOS control extends capability to allow the operator to control the machine at greater distances and in areas
not directly in line-of-sight. Manual hauling to the dump site would normally be used with TeleRemote ELOS
control.
A further capability level, which we refer to as TeleRemote Load-Haul-Dump (LHD) control, provides the
capability to execute the complete hauling cycle through TeleRemote control. TeleRemote LHD systems
provide both machine electronics and an operator interface with advanced capabilities to support the com-
plete hauling cycle. The operator could be stationed underground near the operational area or on surface.
TeleRemote LHD control does not require the use of a guidance system nor a mine-wide communications
backbone, therefore the capital cost and maintenance of the system is greatly reduced. TeleRemote LOS,
ELOS, or LHD control capabilities enable new alternatives in mining methods with economic returns realized
through reduced development costs, improved ore recovery, increased productivity through more efficient use
of machinery, and improved personnel safety. Today, robust TeleRemote control technology for all of these
capability levels is available.
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TeleRemote System Advances
Research and development of TeleRemote, teleoperated, and semi-autonomous underground mobile equip-
ment has been an area of substantial work in recent years. In 1990, LKAB tested a teleoperated LHD with
automated haulage at the Kiruna Mine in Sweden (Eriksson and Kitok, 1991). The prototype, developed with
the Toro LHD manufacturer, mucked a total of 50,000 tonnes of ore before the project was completed. Ve-
hicle guidance was provided by a guide wire in a concrete road bed. The project was not continued due to
the infrastructure requirements of the guidance system and insufficient speed (12 km/hr) for the mine’s needs.
Also in 1990, Vielle Montagne Sverige developed and tested a teleoperated, guided LHD at the Zinkgruvan
Mine in Sweden (Vagenas at al., 1991). Guidance was achieved by cameras detecting a white line painted on
the back (roof) of the drift and top speeds of approximately 8 km/hr were attained. The Lulea University of
Technology was heavily involved with this project. The prototype hauled 1,200 buckets over a nine month
project test period.
In 1991, Mount Isa Mines in Australia developed a teleloader at the Hilton Mine (Chadwick, 1992). This LHD
teleoperation system uses two cameras, mounted front and back, and does not incorporate any guidance.
Teleloaders have become integrated into the mine operations. Mintronics (Brophey and Euler, 1993) began
development of the Opti-Trak guidance system for underground truck haulage in 1987 and the system has
been commercially available since 1992. The guidance system uses front and rear mounted scanning lasers
on the vehicle to follow a reflective tape reference strip mounted on the drift back. A number of vehicle control
functions are initiated based on reflective bar codes mounted beside the reference strip.
Inco Limited in Sudbury Ontario commissioned a teleoperated guided LHD in 1992 and added a second in
1993 at the North Mine in Sudbury (Baiden, 1993, Baiden and Henderson, 1994). The guidance system uses
two video cameras (one front, one rear) angled up to follow an optical light track suspended from the back of
the drift. Inco Limited have successfully demonstrated the ability for one operator to control two machines by
hauling automatically between teleoperated loading and dumping.
Noranda Limited began testing an optical guideline guidance system for an LHD underground in 1990 and
work has been ongoing since then (St-Amant et al., 1990, Grenier et al., 1994). Guidance is achieved by two
cameras, pointing up and ahead of the vehicle (one in each direction), detecting a reflective tape strip sus-
pended from the back of the drift. Prototype LHD’s and trucks have been used to develop this system at the
Mattagami and Brunswick Mines. The system has been performance tested at 15 km./hr.
Colorado School of Mines in conjunction with the USBM developed a guidance system for semi-autonomous
underground vehicles from 1989 to 1993 (Steele et al., 1991, Lane et al., 1994). The guidance system
utilizes ultrasonic ranging sensors to follow the walls of the mine drifts. Work has included testing of ultra-
sonic sensors underground and the development and testing of a prototype semi-autonomous mine haul truck
in 1993.
In 1996, a collaborative Canadian project called “Tele-Remote Assisted Mining (TRAM)” was initiated to
develop TeleRemote control technologies and test these in operations of an LHD (Neuburger and Aitken,
1985, Aitken et al., 1996). The TRAM project was launched under PRECARN/PERK sponsorship, an Ontario
consortium which sponsors pre-competitive research and development, with project participants Cameco
Corporation, Saskatoon, Thomson Technology Ltd., Sudbury, and the Defence Research Establishment
Suffield near Medicine Hat, Alberta. The TeleRemote LHD system has completed initial commissioning tests
with an interim communications system at Cameco’s Eagle Point Mine in northern Saskatchewan. Extensive
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operational tests are scheduled for early 1998 following installation of a more advanced broadband communi-
cations system (Baiden, 1996) now commercially supported by Automated Mining Systems of Aurora Ontario.
The harsh mining environment naturally poses significant challenges to TeleRemote control and autonomous
guidance. Unlike the known and structured manufacturing environment, where robotic systems perform
repetitive functions under constant conditions, mining applications often involve wet operating conditions,
changing, uneven and muddy road beds, restricted clearance for sensors above the vehicle, variable video
response due to limited lighting conditions, and falling rocks and debris. These factors drive component
selection, packaging requirements, sensor selection and positioning, and algorithmic complexity in order to
develop systems capable of robust autonomous performance in the unstructured mining environment. Al-
though autonomous capability is expected to hold great future promise, careful consideration must be given to
creating an economic balance between the needs of mine operators today and the capability of today’s
technology. TeleRemote operations, offering LOS, ELOS, or LHD levels of capability, are well suited to today’s
technology and mining methods.
TeleRemote Control Systems
TeleRemote systems are based on trained and skilled human operators who guide the machine from a safe
position off of the machine. TeleRemote Line-of-Sight (LOS) control typically only provides very simple
machine interfaces and limited information for display to operators since the machine is operating within very
limited distances. The next logical advance for this capability is TeleRemote Extended Line-of-Sight (ELOS)
control in which the operator controls the machine from a local position, but is provided with video and audio
feedback in order to control the machine at greater distances and around corners. Still more advanced
capability, referred to here as TeleRemote Load-Haul-Dump (LHD), provides improved functionality not only
on the machine but also in the human machine interface or operator control station. TeleRemote LOS and
ELOS are used primarily for the loading operation with manual hauling to the dump site. TeleRemote LHD
control provides the capability to remove the operator from the machine for the complete hauling cycle.
Teleremote systems consist of the following primary components:
• Machine mechatronics;
• Communications systems; and
• Human machine interface.
In this section, we expand on these primary components to provide an overview of current capabilities in
TeleRemote systems with LOS, ELOS, and LHD levels of capability and functionality. Although many applica-
tions can benefit from TeleRemote control, examples provided in the following sections focus primarily on
operation of LHDs.
Machine Mechatronics
Today, machine automation is recognized as a broad field formed from a number of interdisciplinary areas
including mechanical design, materials, machining and fabrication, kinematics, dynamics, planning systems,
control, sensing, actuation, communications, programming languages, computer architectures, artificial
intelligence, and systems integration. The design, development, integration, and deployment of TeleRemote
8. TeleRemote Control - It Comes of Age Page - 8
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mining systems combine aspects of mining, electrical, mechanical, and industrial engineering with computer
science, mathematics, physics, and economics. Mechatronics is a relatively new term used to describe an
ensemble of some of these cross-disciplinary areas, particularly mechanical and electrical engineering.
Mechanical, hydraulic, and engine control interfaces required to prepare a machine for TeleRemote control
are now quite mature and are rapidly improving. These interfaces include hydraulic stage kits, as illustrated in
Figure 2, to allow both manual and automatic control of hydraulic subsystems, electrical interfaces to elec-
tronic fuel-injected engines (such as DDEC engine control), as well as all sensors for machine operations,
health and performance monitoring, and all actuators to drive relays or valves to control machine functions.
Recent challenges have focused more on electrical interfaces to mechanical subsystems and the exploitation
of advances in microcontroller and computer communications technology to improve capabilities, perfor-
mance, and reliability of TeleRemote control systems.
Figure 2: Proportional electro-hydraulic stage kits used to provide
both manual and automatic control of mining equipment.
Early LOS control systems used simple RF receivers on-board the vehicle with electronics to directly drive
discrete valves. This approach proved the initial concept and viability of LOS control, but could not provide the
necessary safety levels and electrical isolation. The next stage of development continued the use of simple
RF receivers, but introduced Programmable Logic Controllers (PLCs) to interpret the radio commands and
modify them according to a rule-based ladder logic program. This system introduced software logic into radio
control and provided improved safety and monitoring of machine health. In 1992, Thomson Technology Ltd. of
Sudbury Ontario introduced a commercial “Universal Interface” for remotely controlled LHD’s. A schematic
representation of this unit with the machine stage kits is shown in Figure 3. This system is also PLC-based,
but standardized the machine valve wiring and electrical interface to the machine wiring harness. This system
provides a standard set of rules and methods of wiring that carries across different LHD platforms and inter-
faces to standard radio control manufacturers.
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Figure 3: PLC-based LHD Universal Interface system and schematic layout
showing standardized connections between the various radios and the PLC,
and between the PLC and machine valves and sensors.
(Thomson Technology Ltd., Sudbury Ont.).
PLC interfaces are attractive because of their low cost, ease of programming, and general acceptance due to
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simple internal functionality. These systems were originally designed for TeleRemote LOS applications. They
are typically quit large, have complex internal wiring, and increase the complexity of the machine wiring
harness since all electo-mechanical subsystems needed for TeleRemote control parallel the existing machine
systems. The PLC-based interface unit is commonly located where space is available with protection from
debris or loose. Wiring harnesses are then added to the machine to provide control signals from the radio
receiver unit to the PLC, dash interfaces to isolate manual controls, and data and control paths to all sensors
and actuators on the machine. The hardwire cabling, although fairly reliable, parallels the existing machine
wiring harness and results in more complex trouble shooting and additional down time of the machine for
electrical fault isolation and repair. More importantly, PLCs do not offer flexibility to easily adapt to new
applications, provide very limited capabilities in machine health and performance monitoring, and do not
provide intelligence or upgrade paths to higher automation.
Receiver
Backplane
CAN
Interface Cable
Power
Cable
FRONT
JUNCTION BOX
TO ACTUATORS
Steer
Right
Boom
Down
Bucket
Dump
Steer
Left
Boom
Up
Bucket
Roll
Radio On
REAR
JUNCTION BOX
TO ACTUATORS
Fire
Supp. Accel
SBrake
Radio On
Pbrake
Spare Spare
Dash Isolation Module
.
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RM8877665544332211
8 Isolation Modules
(Optional Analog/Discrete Inputs)
Manual / Remote
Switch
D
F
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A
B
NODE 'E'
DDEC
E
LOW
HYDRAULIC
LEVEL
SENSOR
ENGINE OIL
PRESSURE
SENSOR
ENGINE
COOLANT
TEMPERATURE
ENGINE
OIL
TEMPERATURE
SENSOR SENSOR
VCAN LOW
COOLANT
LEVEL
SENSOR
DDEC LOW
COOLANT
LEVEL
SENSOR
FE
A
NODE 'B'
TRANSMISIION
B
FORWARD
PRESSURE
SWITCH
REVERSE
PRESSURE
SWITCH
TRANSMISSION
PRESSURE
SENSOR
TRANSMISSION
TEMPERATURE
SENSOR
D
F
C
E
A
NODE 'D'
BRAKES
D
BRAKE
PRESS.
SENSOR
SERVICE
BRAKE
VALVE
FIRE
SUPPRESSION
PARK
BRAKE
VALVE
HYDRAULIC
TEMP.
SENSOR
CAMERA
SELECTOR
Transmission & CameraBrakes & HydraulicsFuture
Expansion
CAN
Expansion
VCAN BASED LINE OF SIGHT
RADIO CONTROL
EXPANSION TO
EXTENDED LINE OF SIGHT
Transmitter
(Facing Operator)
Engine Monitoring & Control
Figure 4: TeleRemote LOS control system offering basic machine functionality is shown in the upper half
of the figure with dash isolation and electronic interfaces to junction boxes for control of machine valves.
TeleRemote ELOS capability is added in the lower half of the figure through distributed control
and sensing nodes connected to the main processor with a Vehicle Control Area Network
(Thomson Technology Ltd., Sudbury).
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Recent advances in TeleRemote control have replaced the PLC implementation with computer systems,
microprocessors, microcontrollers, and distributed control architectures with on-board communication net-
works. These systems are better suited to TeleRemote ELOS and TeleRemote LHD control applications. The
embedded hardware and software, and the communications architecture support local execution of self
diagnostics, control laws, and rule-based safety systems at the node level. Improved capabilities for machine
health and performance monitoring can be added as needed through additional nodes which can be adapted
to a wide variety of sensors for an array of applications
Figure 4 shows a schematic representation of TeleRemote LOS and ELOS distributed control systems. The
upper half of Figure 4 includes the operator control pendant and the machine receiver unit. In strict LOS
applications, only dash isolation and junction box interfaces are needed to provide basic functionality. Expan-
sion for ELOS applications is shown in the lower half of Figure 4. Distributed control and sensing nodes are
added as required for engine, transmission, brakes, hydraulics and camera control and sensing. This system,
however, still involves added complexity in machine wiring since the original machine wiring harness is
retained and that required for TeleRemote operations is added in parallel.
In Figure 4, control and sensing nodes are connected through a Vehicle Control Area Network (VCAN). This
network supports the Control Area Network (CAN) protocol. CAN is an ISO defined serial communications
bus which has high bit rates, high immunity to electrical interference, error detection capabilities, and mes-
sage collision arbitration. The CAN communications protocol conforms to the Open Systems Interconnect
model and represents the data link and physical layers of this model. CAN communication systems are now
an automotive standard with full industry support. Small operating systems running on the microcontrollers at
each node control the CAN communications between nodes and allow quick non-invasive diagnostics and
software upgrades through the VCAN network.
Figure 5 shows a schematic of a distributed Vehicle Control Area Network for TeleRemote LHD control. The
system shown in Figure 5 was developed by Thomson Technology Ltd, Sudbury, during participation in the
PRECARN TRAM project. In this system the wiring harness of the LHD was replaced by the VCAN system.
Existing manual hydraulic controls were replaced with electronic subsytems and a vehicle dash and health
monitor was added for manual operation. Interprocessor communications use the CAN protocol, and com-
plete machine functionality is provided through VCAN interfaces to machine valves and sensors. This system
results in reduced complexity and simplified trouble shooting for electrical subsystems. Full TeleRemote LHD
control is provided through an ANCAEUS (Eirich and Kramer, 1991) operator control station described further
below.
The distributed control and sensing approach described above is well-suited for expansion of capabilities from
TeleRemote LOS control (upper half of Figure 4), to TeleRemote ELOS control (lower half of Figure 4) to full
TeleRemote LHD control (Figure 5). Moreover, the functionality and flexibility of these systems prepare the
machine for integration of higher levels of automation, such as semi-autonomous guidance, by providing an
upgrade path through addition of computing and sensing nodes as mature technology becomes available.
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STEER RIGHT
B
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D
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BUCKET DUMP
NEUTRAL
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R 2
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MAIN POWER
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CHECK ENGINE
OFF ON
ENGINE STOP
OVERRIDEFIRE SUPPRESSION
PARK BRAKE HORN
FRONT LIGHTS REAR LIGHTS
ENGINE STOP ENGINE START
CAN1
GEAR
SELECT
THROTTLE
STEERING
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DDEC
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BOOM
MAIN
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PANEL
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PEDAL
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JOYSTICK
BOOM/BUCKET
JOYSTICK
GEAR
SELECTOR
BRAKE
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VEHICLE
DASH &
HEALTH
MONITOR
BATTERY
BATTERY
+ _
+ _
D
F
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A
NODE 'D'
BRAKES
CA
NODE 'A'
STEERING
BRAKE
PRESSURE
SENSOR
HORN
SERVICE
BRAKE
VALVE
FIRE
SUPPRESSION
PARK
BRAKE
VALVE
HYDRAULIC
TEMPERATURE
SENSOR
FE
A
NODE 'C'
BOOM / BUCKET
C
B
FE
A
NODE 'B'
TRANSMISIION
CLOG FILTER
BREAK OUT
BOX #1
FILTERS 1,2,5
CLOG FILTER
BREAK OUT
BOX #2
FILTERS 3,4
ACCUMULATOR
PRESSURE
SENSOR
HYDRAULIC
PRESSURE
SENSOR
FUEL
LEVEL
SENSOR
BREAK OUT
BOX
STEER
LEFT
STEER
RIGHT
BUCKET
DUMP
BOOM
DOWN
BOOM
UP
BUCKET
ROLL
FORWARD
PRESSURE
SWITCH
REVERSE
PRESSURE
SWITCH
TRANSMISSION
PRESSURE
SENSOR
TRANSMISSION
TEMPERATURE
SENSOR
BREAK OUT
BOX
REVERSE
FORWARD
1st
GEAR
2nd
GEAR
3rd
GEAR
FRONT
LIGHTS
BREAK OUT BOX
D
F
C
E
A
B
NODE 'E'
ENGINE
COOLANT
TEMPERATURE
SENSOR
ENGINE
OIL
TEMPERATURE
SENSOR
VCANLOW
COOLANT
LEVEL
SENSOR
DDECLOW
COOLANT
LEVEL
SENSOR
LOW
HYDRAULIC
LEVEL
SENSOR
ENGINE OIL
PRESSURE
SENSOR
HARD WIRED
TO START
RELAY
COIL
DDEC
REAR LIGHTS
REAR JUNCTION
BOX
DIAGNOSTICS
DDEC
HARNESS
ECM
POWER
Hydr. Pr. Hydr. T.
Coolant T.Accum. Pr.
Brake Pr.
Trans. Pr.
Eng. Oil
Pr.
Eng. Oil T.
Trans. T. Bucket
Ang.
Boom
Ang..
CAN
Nodes
Battery
Fuel Lev.
Steer Ang.
Clog Filt.
Coolant
Level OK
Hydr. Fluid
Level OK
DCAB
E
Isolated Battery Backup
Access For Options:
• Radio Control
• Vehicle Health
• Load Weighing
• Vehicle Tracking
• Traffic Management
• TeleRemote Control
• Guidance
• Obstacle Detection
POWER
STEER LEFT
CAN
Figure 5: Distributed control nodes and Vehicle Control Area Network (VCAN) for on-board
communications systems can reduce existing wiring complexity and provide superior
functionality and flexibility for addition of advanced control and sensing modes
(Thomson Technology Ltd., Sudbury Ont.).
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Communications Systems
Historically, TeleRemote LOS control has been based on one-way 450MHz communication links from the
control pendant transmitter to the receiver on the machine. Low Baud rates without hardware flow control
were typical which can result in unnecessary control latency and severe problems due to communications
dropouts. Today, commercial smart tranceiving modems are available with superior performance characteris-
tics. The system shown in Figure 4, for example, employs tranceivers in the pendant and on the machine with
full duplexing links based on 900Mhz frequency hopping (440 channels) spread spectrum methods for robust
two-way communications. Frequency hopping with hardware flow control offers some measure of frequency
diversity to overcome nulls in the drift. This system has given excellent results for TeleRemote LOS applica-
tions.
For TeleRemote ELOS applications, control of the LHD may be required at greater distances or out of sight of
the operator. To add this capability, as illustrated in the lower half of Figure 4, video subsystems transmit
imagery to the operator at the control pendant. Video-audio transmitter/receiver pairs operating at 2.4GHz are
used with small video screens at the pendant for improved operator control of the LHD.
Figure 6: Example layout for modular video/control communications system for
TeleRemote ELOS or TeleRemote LHD control systems.
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A further level of capability, shown in Figure 6, can be used for either TeleRemote ELOS or TeleRemote LHD
control. In this case, remote control is not dependent on the mine communications system, nor are mine-wide
communications required. Instead, modular video/control substations are placed for sufficient coverage in the
operational area. Control data, video, and vehicle status information are received/transmitted between the
machine and the video/control substation. The substation then provides the link to the TeleRemote ELOS
control pendant or TeleRemote LHD control station with coaxial or fibre optic cables.
This approach offers incremental capability at reasonable cost covering TeleRemote LOS, ELOS, and LHD
control applications as may be required by the particular mine layout and methods used. Moreover, existing
mine communications infrastructure need not be replaced nor must it satisfy some minimal performance
criteria. The TeleRemote communications system is local to the operational area and can be moved where
needed as operations continue in the mine.
Human Machine Interface
Human machine interface requirements change significantly between TeleRemote LOS, ELOS, and LHD
control applications. For TeleRemote LOS control, the operator can see the machine operations directly and
does not rely on video or audio feedback through the radio. Many LOS pendants provide simple LEDs for
warning indications. Some, including that shown in Figure 3, have small LED screens for operator messages
and/or lighted keypads for indication of the state of specific subsystems (such as park brake).
TeleRemote ELOS control is intended to provide the capability to operate at extended distances or beyond
direct line-of-sight. Usually this requires video transmission from the machine with display capabilities at the
pendant together with audio feedback from the machine. As more advanced capabilities are required, more
health and performance information can be collected at the machine, as illustrated in the lower half of Figure
3, and transmitted to the operator workstation. In this case simple pendant interfaces may not be sufficient
and the next level of human machine interface, such as those shown in Figure 6 or Figure 7, may be required.
Figure 7 shows the TeleRemote LHD system developed under the PRECARN TRAM project. The LHD wiring
harness was mostly removed and replaced with the VCAN distributed control and sensor system illustrated in
Figure 5. Two of these VCAN nodes are also shown in Figure 7. For full TeleRemote LHD control, a modified
Boler trailer is used for the control station and houses the telemetry subsystems and control station comput-
ers. The trailer is towed by the LHD and stationed on the same level as the active stope. Figure 7 also
includes a snapshot of the operator workstation inside the trailer. An ergonomic control chair provides the
operator with two joysticks, gear shifter, and footpedals for LHD control. The control station software was
adapted from the generic ANCAEUS (Eirich and Kramer, 1991) control system originally developed by the
Defence Research Establishment Suffield for military applications. The control station display shows live video
from the machine, a moving mine map of the operational level, and general windows for machine health and
status displays. Audio and visual alarms are used to alert the operator to system faults with details available
through the windowing system.
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Figure 7: LHD system developed under the PRECARN TeleRemote Assisted Mining Project
employs a full implementation of the VCAN system and
ANCAEUS control station for TeleRemote LHD applications.
Conclusions
TeleRemote control systems have now reached a level of maturity that offers tremendous potential for mining
automation. With the success, broad application, and acceptance of TeleRemote LOS control, many research
and development initiatives have taken bold steps toward complete- or semi-autonomous control. The tech-
nology and mine infrastructure investment required to support autonomous capability has resulted in limited
acceptance of these systems at this time. Advanced levels of TeleRemote control, spanning line-of-sight,
extended line-of-sight, and full load-haul-dump applications, offer affordable intermediate capabilities and
flexible upgrade paths to future autonomous operational modes. Robust and proven implementations of these
three levels of TeleRemote control are available with today’s technology.
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