collision avoidance systems
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Collision Avoidance Systems CWSCompiled By B.Arunachalam, Manager- Hospet
Extracts from Collision Avoidance Systems Technical Report April 2007 by Anglo American
General
In many cases the mobile machine operator are not aware of light vehicles around their
machine. Due to the size of haul trucks, the operator is not able to see significant areasaround the machine. Figure shows blind spot areas around a small 50ton capacity haul truck.
Most collisions occur in congested areas in the pit or park up areas
Light vehicles are the major at risk vehicles
Collisions with light vehicles primarily happens because the heavy vehicle driver did notsee the light vehicle
Whilst heavy to heavy vehicle collisions causing injuries occur, the risk and consequence is
far less than light/heavy vehicle collisions
Any system chosen must reduce the current risk. When a collision situation (routecontention) has been detected the CWS system is expected to series of progressive alerts to
the driver. These progressive alerts indicate that the distance between the vehicles is closing
and the driver should take action. These progressive warnings can escalate from audio tone
only to audio, visual, or other warning modes.Driver vehicle interface requirements
These requirements define specific ways in which the CWS systems interface with the driver(i.e., Driver-Vehicle Interface), and include indicators, displays, and warning methods.
CWS should utilize different audible tones (e.g., different pitches, patterns, lengths, etc.) or
tactile warnings to provide multiple progressive warnings as an object crosses the warningthresholds.
The CWS system should include a visual indicator when no vehicles or objects are posing a
hazard. The indication may be provided by an instrument panel warning light or an indicator
that is integral to each system.The CWS system should use a visual indicator to provide system operational status. This
status may be indicated by an instrument panel warning light or an indicator that is integral toeach system. The CWS system should use a visual or audible indicator to indicate a systemfailure or malfunction. This status may be indicated by an instrument panel warning light or
an indicator that is integral to the system.
The CWS system indicators should be clearly discernable in direct sunlight and at night.Consideration should be given to adjust the brightness of the indicators during night
operation. Excessively bright indicators have been found to be a distraction to operators.
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1.0 TYPES OF COLLISION AVOIDANCE
The first and most prevalent, is close proximity (
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Distance) to prevent collision by bringing truck to a complete stop.
For the purposes of these calculations two actions that an operator could take to avoid collisions a
assumed. The first avoiding action is to bring the machine to a complete stop from a predeterminspeed. The second type of avoiding action was to reduce the speed of the machine from a
Predetermined speed to 20km/h. At 20km/h it was determined that the operator could safely swerve
avoid a collision without loosing control of the machine and incurring secondary collisions such
driving into a berm or overturning. It can be seen from Table 1 that for both scenarios the slow speclose proximity class systems are effective up to 20km/h.
Beyond this speed this class of devices will not provide adequate warning time and insufficient time
stop or slow the machine to avoid a collision.Technologies that specifically target close proximity type collisions are radar based, low frequency radi
identification (RFID), and high frequency RFID. Technologies using Mesh Networking and Machine
Vision Cameras are currently being developed. It should be pointed out that most long range high speedtype collision avoidance technologies would also be suitable for close proximity-high speed collisions
albeit at a higher capital cost.
1.3 Collision scenarios Figures show the typical type collision scenarios.
Short
Range
Radar
Low
Freq-
RFID
Mesh
Network
High Freq-
RFID GPS
Long
Distance
radar
SPEED
Decele
ration
Distance travelled
to bringmachine
undrer control
(20km/h) in order
to erve=minimum
CASwarning
distanceneeded) Preco Hazard
Mesh
Network
RFIDCAS
CAM GPS VORAD
km/h m/s'2
5 -1.050 0.0Yes Yes Yes Yes Yes Yes
10 -1.050 2.8Yes Yes Yes Yes Yes Yes
15 -1.050 4.2Yes Yes Yes Yes Yes Yes
20 -1.050 5.6Yes Yes Yes Yes Yes Yes
25 -1.050 15.2 No Yes Yes Yes Yes Yes
30 -1.050 28.7 No No Yes Yes Yes Yes
35 -1.050 40 No No No Yes Yes Yes
40 -1.050 55.2 No No No Yes Yes Yes
45 -1.050 72.2 No No No No Yes Yes
50 -1.050 90.6 No No No No Yes Yes
55 -1.050 111.8 No No No No Yes Yes
Will the collisionavoidance technologybeable to warn
the operator insufficent timeto allowhimtoslow
downhis machineto 20km/handtakeevasiveaction.
It isassumedthat evasive actiontakenat higher
speedswill result inasecondarycollision (drivinginto
the bermfor e.g)
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Figure 1 Collision at intersection where one machine fails to adhere to the stop signal
Figure 2. Lane departure one truck drifts into the oncoming lane.
Figure 3 Rear truck moving faster and front slower
Figures 4,5, 6 &11 Haul truck reversing into parked obstacles that are in the blind areas
of the operator
Figure 7 . Light vehicle overtaking haul truck
Figure 8 Haul truck parked or moving inside the swing radius of shovels, draglines etc.
Figure 9. Haul trucks simultaneously reversing at crusher / tip or inside the pit
Figure 10 Haul truck reversing towards an embankment.
Figure 12. Haul truck on collision course (at slow speed) with fixed structure.
Figure 13. Haul truck runs into berm.Figure 14. Truck following with differential speed. Forward machine is slowing
down. There is potential for duck tailing or forward machine is parked in which case a
collision is possible
1.4 Collision scenarios --:- Long range (0m 150m) High Speed (0km/h speed
55km/h) collision warning systems
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The second class of collision warning system is high speed-long range collision avoidance
systems. These systems operate on the principle of detecting potential threats (light vehicles,other haul trucks etc.) in the direction of travel and providing sufficient warning time to the
operator to take action.
Action could include applying brakes to bring the machine to a stop or it may involve
slowing the machine to a controllable safe speed before swerving to avoid a collision. Table 1shows the calculations of stopping distances and times. It can be seen that this class of CAS
that these systems would operate at speeds up to 55km/h where stopping distances of 150m
are required on a downhill gradientHigh frequency RFID which typically has a range of 50m 70m would not provide sufficient
warning time above 35km/h. At 35km/h the operator needs approximately 65m to bring the
machine to a stop. Hence the 50m warning is insufficient. If it were possible for the operatorto slow the machine down to 20km/h and take action then high frequency RFID would be
effective up to a speed to 40km/h
Long distance radar and GPS have long ranges. Long distance radar can detect up to 150m
while GPS based systems are effectively limited to 500m by the vehicle to vehicle wirelesscommunications network. Both these technologies would be able to provide adequate
warning to the operator at all speeds.
Lane departure one truck drifts into the oncoming lane .
A truck drifts onto the oncoming lane. Several factors can cause this including, driving
around a curve, loss of concentration due to operator fatigue, avoiding a slow or parked
vehicle ahead etc. A long range CAS would detect a potential collision and provide warningto the operator to correct course
Slow moving machines or parked machines pose a potential hazard. This can be even more
hazardous if the parked machine is around a curve. A long range CAS system should be ableto detect slower moving or parked machines in time to allow the fast moving machine behind
to slow down or stop.
Haul truck runs into berm.
Several factors can lead to a truck running into a berm. Taking avoiding action, operator
fatigue, poor road conditions are some of them. Technologies that use tags or receivers
(RFID or GPS) will not be effective in preventing collisions with embankments.Technologies are available to detect if the operator is driving within his lane and alarm the
operator if he drifts out (Accumine, Dephi systems)
2.0 COLLISION WARNING TECHNOLOGIES
These technologies include Radar, Radio frequency Identification, Mesh Networking, GPS
and Machine Vision systems. The aim is to describe the operation of these technologies,discuss their advantages and limitations that are applicable to surface mining conditions.
2.1.1 Radar
There are several radar based CAS systems.
Fitted only to the host unit but can detect other people, objects and equipment Works on lineof site although some technologies use multiple units and software to bend the signal
slightly to try to avoid spurious alarms
Antennas fitted outside the vehicle with alarm units (rows of lights or pie chart screen forvisual and audible alarm) fitted inside cab.
2.1.2 Basic principle of radar (RAdio Detection And Ranging)
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The basic principle behind radar is a signal is transmitted, it bounces off an object and it is
later received by some type of receiver. Radars use certain kinds of electromagnetic wavescalled radio waves and microwaves.
EM waves transport energy through a vacuum this implies that the speed of the signal is
constant (c = 292,792,458 m/s). This feature is used to determine distance calculations to
targets and is called ranging.. Once the radar receives the returned signal, it calculates usefulinformation from it such as the time taken for it to be received, the strength of the returned
signal, or the change in frequency of the signal. This information is then translated to reveal
useful data: an image, a position or distance away and the velocity (speed) of a haul truck.
2.1.3 Radar for mining equipment
There are several types of radar systems which include Pulsed, Synthetic Aperture Radio,
Doppler, Continuous Wave etc. Collision avoidance systems for mining equipment that useradar as their primary technology have the advantage that they are low cost.. Another
advantage of radar its ability to work in all weather conditions (rain, mist, fog etc.)
although significant mud build up onto an antennae can cause operation to deteriorate. Radar
systems are relatively easy to install. The positioning of the antennas is critical. If the unitsare installed too low in front or behind then too many rocks etc. will be detected. Mounting
the unit too high may cause the radar to miss low objects which, depending on the size of the
haul truck, might be light vehicles or people.Radar systems can detect any object that is able to reflect the EM signal back. Hence other
vehicles, people, rocks, buildings, trees etc will be detected. The detection of rocks and
foliage may be seen as a false alarm. Too many false alarms could be seen as a nuisance tooperators. Nuisance alarms are those emanating from objects of which the operator is already
aware or from objects that pose no danger. Too many nuisance alarms may result in an
operator not taking a system seriously and ignoring alarms even when a potential collision isimminent. Because of the potential nuisance alarms. In addition it is advisable to integrate
radar systems with cameras in order to minimize the number of LCD displays inside the
machine. The forward and rear cameras should be activated by a switch on the transmission
and the radar alarms should be superimposed on the picture.
2.2 Radio Frequency Identification (RFID)
2.2.1 How it works
Radio Frequency Identification operates on a Reader and Tag principle. In its simplest form
RFID systems work on the principle of inductive coupling. The reader's antenna coil
generates a strong, electro-magnetic field, which then penetrates the tag. The tag isessentially a coil many windings of copper. The electromagnetic field induces a voltage
that allows the tag to function. The tag or more accurately called the transponder sends back
an electromagnetic signal to the reader. Each tag normally has a unique identity, so when the
reader receives the signal from the Tag it can identify where it came from.RFID systems can be classified as active or passive, high frequency or low frequency.. These
features are important when evaluating RFID systems for collision avoidance, because they
determine the range (read distance) of the system as well as the effect of the metals etc on thesystem.
2.2.2 Nautilus Buddy Haul Truck System
Nautilus International has a low frequency RFID product called the Nautilus Buddy Haul
Truck System. It is 125 kHz system that uses two loop antennaes to propagate a magnetic
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signal. The system uses a radio frequency communication link to transmit signal back to the
haul truck. One Antenna is mounted at the front of the truck close to the front railing and asecond at the rear. These antennas radiate a field which surrounds the truck completely,
including underneath the truck. A tag (Belt pack) is mounted on people or on light vehicles.
The range of the coverage is shown where it can be seen that it fluctuates between 15m in the
front of the truck to approximately 9m on the sides and the rear of the machine. The completeBuddy system CAS equipment is shown below .
The system calculates the distance that the potential threatening light vehicle/ haul truck is,
and displays this information on the haul truck display as well as on the Tag inside the light
vehicle. The system uses two antennas to differentiate if the target is approaching frombehind or in front. The system has an optional Cab Video Unit where the data can also be
displayed This display data includes warning messages for the driver and also shows whether
the "target" is a pedestrian or a small vehicle. An audible alarm built into the Cab Video Unitwill increase in frequency as the Haul truck approaches the "target".
Once the Haul truck gets too close to the "target" the Haul truck's air horn will automatically
sound and the headlights will flash on and off to warn personnel and small vehicles in closeproximity to move away to a safe distance.
Summary
The Nautilus system has excellent coverage all around the machine and even underneath itmaking it suitable for close proximity slow speed collisions. On the other hand the system is
expensive to install and every haul truck and light vehicle needs to be equipped with the
system for it to be effective. The size of the Belt pack could also be a deterrent for adoption.
Also against this system is the relatively high cost of the unit.
2.3 High Frequency RFID systems Advanced Mining Technologies (AMT) CAS-CAMSystem description
Radio Frequency Identification This technology uses radio frequency signals and detection via antennas.
Requires line of sight between transmitters and receivers.
Requires each unit or object to be fitted with the technology.
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Is often combined with camera technology with some manufacturers using several units to
add sophistication to the alarm logic that can be programmed, and switching of cameraslooking at the side of the equipment where the
potential collision has been detected.
On smaller vehicles and equipment the RF unit is combined in rotary flashing light with just
an alarm box in the cab Can be programmed to alarm at set distances, and even identify specific vehicles with the
alarm
Is the same technology used in modern hospitals to keep track of patients, and in factories tokeep track of tools and components.
The AMT CAS-CAM system is a high frequency RFID system. It operates on the 433MHz
frequency which puts it into the high frequency range.. the tags provide their own power andare not dependant on the EM field emitted from the reader in order to communicate.
The CAS-CAM system consists of readers, tags and cameras. Tags are installed on each
person, light vehicle, heavy vehicle and other items of value. Figure shows the RF unit as
well as the camera installed on the rear of a haul truck.. Heavy Vehicles also have videocameras and an LCD video display unit. The images from the camera and the alarms from the
RF units are displayed, simultaneously on the LCD unit inside the haul truck.
AMT CAS-CAM RFID reader and camera. The Radio Frequency system transmits
digitally coded data such as tag identification number, tag type, vehicle status and tag status.
This allows the systemto discriminate between classes of objects e.g. Heavy Vehicle (HV), Light Vehicle (LV),
Stationary Object (SO) Personnel Tag (PT), Test Station (TS) etc. The system comes in three
options:
1. Video Only system for enhanced vision applications: CAS-CAM2. RF Only system for automatic object detection: CAS-RF
3. Video & RF systems (vision & object detection): CAS-CAM/RF
2.4 GPS Based systems2.4.1 How GPS works
The Global Positioning System (GPS) consists of a constellation of 27 Earth-orbiting
satellites (24 in operation and three extras in case one fails). These satellites are in a fixedorbit approximately 20,000km above earth.. A GPS receiver, such as a handheld unit or an
electronic circuit board type receives radio messages from these satellites. The receiver then
calculates its distance from the satellite sending it a message. The receiver obtains messages
from at least three satellites in order to triangulate its position on the earths surface.
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Typically a receiver would use around 6 to 12 satellites (if available) to triangulate its
position. The more satellites available the more accurate the position fix. Because the earth isrotating, satellites appear and disappear over the horizon, hence the more satellites that are
available not only increases the accuracy but also reduces the risk of loosing accuracy.
GPS Technology
Each vehicle or machine is fitted with a GPS unit The individual vehicle or machine positions as determined by GPS are transmitted to a
central computer and are scanned for potential collisions
If a potential collision is detected warnings are sent to the vehicles or machines involvedusing radio transmission
2.4.2 GPS based collision avoidance
GPS by itself cannot do collision avoidance it is simply a means to establish position. Byknowing the positions of vehicles in a mine and communicating these positions to machines
it is possible to start to have the first part of a collision avoidance system based on GPS
positioning. The principle of a GPS based collision avoidance system is as follows: - Each
machine is equipped with a GPS receiver to obtain its position - In addition a communicationsystem is required on each machine in order to broadcast its position as well as listen to the
position of other machines in the vicinity (0 500m range) around. The communication
network is probably where the most differentiation occurs with GPS based systems. - Oneach machine calculations are performed to see if any machine (light, heavy etc. is a threat
and an alarm is activated if it is a threat.
2.4.3 Acumine Proximity Detection System.
The Proximity Warning System is a GPS based system that operates on Haul trucks, Light
vehicles as well as People. Three modules are used: Haul Truck Proximity System (HTPS),
Light Vehicle Proximity System (LVPS), Personnel Proximity System (PPS) and a BaseStation. The HTPS alarms the haul truck driver when another truck, a light utility vehicle or
personnel is within the defined proximity of the haul truck. The haul truck forms an ad-hoc
mesh network with these agents, all of which are equipped with GPS, and broadcasts its
position and velocity.. The HTPS will generate a different alarm according to the threat level,e.g. truck approaching in front, vehicle behind etc.
The system uses a dedicated on-board computer for processing and alarming in the haul truck
and light vehicles. A Personal Digital Assistant (PDA) is used to warn personnel such aspedestrians etc. Each agent uses a GPS sensor and an Omni directional antenna for wide area
coverage. All these agents are registered in a single ad-hoc network. The area of operation is
by line of sight of the agents in the proximity and the area of detection. This is possibly alimitation of the system .Systems based on line of sight will typically give ranges of 100m
500m depending on conditions. However if line of sight is obscured such as on ramped
curved roads or possibly at intersections this could become an issue and the system would not
detect with required level of fidelity The operator interface is either a simple audible alarm ora full graphical interface as shown in Figure
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Figure Haul truck graphical interface.
The system can be classed as a long range high speed system There are two major drawbacksof this system. Both relate to the wireless network system that they have adopted. One
drawback involves the issue of line of sight which cannot be guaranteed in mining
environments. The other involves the use of a base station which is a weak link thatcompromises the system long term operation. The entire fleet would be left without a
collision warning system if the base station went down.
2.6 Camera Based Technologies
Collision Avoidance Cameras
A reliable technology of video cameras that the operator can select to give better vision in
the blind spots of the vehicle.
A passive system relying on the operator to choose the camera. (Can be tied into the reversegear signal or other functions)
Multiple cameras (blind side, reversing, etc.) are sometimes fitted. Additional cameras,
whilst increasing visibility, can also complicate use. Modern LCD colour screens are much more reliable than old CRT ones. When correctly
trained operators can choose night settings to reduce night time glare inside the cab.
Installation of cameras will not guarantee that collisions will be avoided. However, theirinstallation gives operators better tools to enable them to do their jobs safely.
2.6.1 Caterpillar WAVS
WAVS stands for Work Area Vision System.. The WAVS system comes in fourconfigurations single camera, 2 and 3 cameras and a special 793 haul truck configuration.
Single camera systems are popular with smaller machines such as wheeled loaders, etc. For
haul trucks multiple camera units are required. The multiple camera units are automatic units
i.e. the rear camera is activated via the transmission. Side cameras are manually activated. Auseful feature is that the operator cannot defeat the cameras (switch them off) as there is no
manual override. This implies that the cameras are always functional. Cameras come in two
configurations 115 degrees and 78 degree options which are used depending on theapplication. The cameras come with special mounting brackets and have internal heaters to
prevent misting in cold weather. The cameras can take vibration and is sealed (High pressure
washer compatible). This makes the WAVS an extremely rugged unit. In comparison theCAS-CAM cameras (discussed above) the CAT cameras can go down to 0.5 Lux (CAS CAM
goes down to 1 LUX).
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.
It is recommended that multiple cameras be installed on haul trucksa. Four cameras (front, rear and two side cameras) are recommended. Depending on the size
of the truck the side camera on the operator cab side of the truck may be omitted. Installing
an additional camera under the truck could help the operator see large rocks which coulddamage tyres.
b. The rear and forward cameras of the system should be linked to the transmission of themachine and activated automatically when the reverse or forward gears are selected.
2.6 Machine Vision Systems
Machine Vision commonly known as Vision Systems is a software technique that analyses
images and outputs characteristics found such as objects, characters, edges, distances, coloursetc. The software does this by analyzing pixels and calculating features inherent in the pixel
configuration. For example objects can be recognized using a technique called pattern
recognition. In pattern recognition the system is trained using sample photographs or images.
Similarly character recognition is performed. Bar coding is one of the most common forms ofmachine vision systems. In Bar coding a laser line is shone on the bar code to illuminate the
bar. The machine recognition software detects the edges of the bar code and calculates the
width of each bar. A combination of different widths constitutes a bar code. Machine visionsystems are very dependant on lighting conditions. Bright light can blur edges and this
confuses machine vision software. Therefore infra red light is often used to illuminate
objects. Nevertheless ambient light still poses a significant problem and needs to be dealtwith in an application. Camera vibration is another threat to machine vision applications and
can blur images. Perhaps the most significant problem with pure machine vision systems
from a collision avoidance perspective is that it is a 2 dimensional technology. This implies
that standard machine vision system will not be able to decipher how far away a threat isfrom the host vehicle. Solution to this problem Stereo Vision. This involves two cameras
which use disparity calculations to calculate distance.
2.7 Pros and cons of various systemsGPS & RF
Pros Cons
Provide an active warning Can be integrated with camerasystems Can display multiple items Easily configurable for many
Not global coverage Susceptible to shadowing effects Not Commercially available Requires lots of repeaters Every unit must be tagged
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different scenarios Reliable components Doesnt differentiate betweenday/night Short and long range
configurations Can provide speed, distance andazimuth information No licensing requirements Can identify individual unitnumbers Can define zones in mine eg high riskzones, speed limits, etc Can integrate with machine
Large objects can shadow smallerobjects Integrity of the systems relies onall components in series Requires additional infra-structure
on site for operation
Cameras
Pros Cons
Allows to view blind spots
Provides positive ID of objects Commercially available
Easily configurable for many different
scenarios (position, units, link to gears, etc)
Reliable
Can provide day/night coverage
Operator/community acceptance
Provides clear lifelike image (orientation issame as what is seen in the mirrors)
Low cost of implementationImprove operator visibility
during manoeuvring
Provide operational as well as safety benefits
Stand alone system per EME
Line of sight detection
Cameras cannot provide an alarmCameras may be effected byenvironmental conditions
Trade of between image clarity and fieldof view
Distance perception is difficult
Not beneficial for high speed
applications Relies on operator to look at the Screen
RFID
Pros Cons
Identifies tagged itemsNo false alarms Wide azimuth at front & rear of vehicle does
not generate false alarms
Not impacted by environmental conditions Provide an active warning
Commercially available
Can link to camera systems
Easily configurable for many differentscenarios
Reliable?
Display can be integrated with camera
systems Doesnt differentiate between day/night
Does not identify untagged items
Requires management discipline to ensure
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Can display multiple tagged items all items are tagged Cannot pin point exact position of tagged
item (general direction only)
Wont detect whether tag is moving or
fixed
Requires licensing to meet country laws Line of sight detection for both units
Global support not currently Available
RFID + Cameras
Pros Cons
Identifies tagged items No false alarms
Wide azimuth at front & rear of
vehicle does not generate falsealarms Not impacted by environmentalconditions Provide an active warning Commercially available Can link to camera systems Can display multiple tagged items Easily configurable for manydifferent scenarios Reliable?
Display can be integrated withcamera systems Doesnt differentiate
Does not identify untagged items Requires management disciplineto ensure all items are tagged
Cannot pin point exact position oftagged item (general directiononly) Wont detect whether tag ismoving or fixed Requires licensing to meetcountry laws Line of sight detection for bothunits Global support not available Cameras may be effected by
environmental conditions (NoteBlack and White cameras muchbetter for night use)
Radar
Pros Cons
Not impacted by environmental conditions
Provide an active warning
Commercially available
Can be integrated with camera systems Can display multiple items
Easily configurable for many differentscenarios
Reliable
Doesnt differentiate between day/night Detects all items
Stand alone
Requires line of sight detection
Large objects can shadow smaller objects
Non-essential alarms - detects items
outside of vehicles travel path? Cannot differentiate for the type of
vehicle, object or person of similar sizesNo positive unit ID on object Detected
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Short and long range configurationsCan provide speed, distance and
azimuth information
No licensing requirements
Can focus detection area to a defined width
(eg width of vehicle for forward travel)
CONCLUSION The recommendations for Anglo American operations are as follows:
1. Each operation needs to undertake a risk assessment in order to determine its risk profile.This should involve studying past collisions, near misses or high potential incidents etc. The
risk assessment should also identify what actions needs to be taken in order to reduce the risk
of collisions between people, mobile machinery and other dangerous machinery. It shouldalso take into account the possible speed of vehicles and determine the minimum and
maximum distances from a vehicle at which the detection and warning alarm are needed to
sound off;2. It is prudent to inform operations that all collision avoidance (CAS) systems / technologies
investigated by the working group were found to have certain technical and operational
limitations. This report provides the necessary technical information discussing limitationsand strengths of each system. Understanding the risk profile of the mine together with the
technical and operational limitations of the CAS system is a key to mitigating the risk of
collisions.
3. Systems that are aimed to be used for anti collision and proximity warning should be notbe named: Safety Systems, rather they should be referred to as Operator Enhancement
Systems. This would ensure that the responsibility remains on individuals for ensuring their
own safety. It also ensures that individuals do not rely solely on the technology for
protection.Surface Mining Equipment
4. It is recommended that multiple cameras be installed on haul trucks.a. Four cameras (front, rear and two side cameras) are recommended. Depending on the size
of the truck the side camera on the operator cab side of the truck may be omitted.
Installing an additional camera under the truck might help increasing tyre life.
b. The rear and forward cameras of the system should be linked to the transmission of themachine and activated automatically when the reverse or forward gears are selected.
c. The working group did not comprehensively evaluate all vendors of camera systems. The
robustness of the camera system as well as the ability to clean the lenses is important factorsto consider when making a choice of camera system.
5. In addition to cameras a RFID based system and/or a radar based system should beinstalled.a. If the risk assessment shows that slow speed, close proximity collisions are the major
threat then radar systems should be installed.
b The Preview Radar* system should be installed. The system has a limitation of an 8mrange and this should be carefully considered before deciding to install the system. A
recommended configuration is discussed in the body of the report.
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c. If the risk assessment shows that high speed, long range collisions are the major threat then
an RFID based system is recommended6 The range of the system chosen should be set to a minimum of 50m. If possible the
maximum range of 100m should be used.
7 The ability of the system to detect near / alongside metal structures such as conveyor belts
should be tested. If loss of detection around metal structures is found then alternative safetyprocedures should be put in place around these areas.
8 A reverse / back up audible alarm should be used for warning while reversing.
9. It is recommended that a reverse / back up audible alarm should be used for warning whilereversing.
Reference NSW web siteCollision Avoidance Technical Report Author(s)H. Faul; M Ruplal (ATD)O. Munoz; E. Riffo (Anglo Base)S. Niven (Anglo Coal)
A. Naidoo (Anglo Ferrous)D. Janicijevic; V. Nhlapo (Anglo Platinum)