MINING NETWORKS & CONNECTIVITY
autonomous haul trucks in operation and for the
first time there was a full breakdown of model
types – namely 85 830E, 134 930E and 28 980E
trucks running on AHS. After 13 years of
commercial AHS operation, the 3 billion tonnes
milestone has just been passed (with 2 billion
only just passed in November 2018) with no
system related injuries or accidents, and the
company expects that by end 2020 it will have
over 15 AHS sites running, up from 11 by end of
last year, for 7+ mining clients, up from 5 in 2019;
with over 350 AHS trucks set to be operating by
end 2020. Notably of the sites so far with Komatsu
AHS, over 50% (seven sites) are running on Nokia
LTE with the remaining six using 802.11 WiFi.
Today’s AHS in the degrees of autonomy sits
above manual operation, assisted automation,
partial automation and conditional automation at
what can be referred to as high automation, where
the trucks have the ability to execute core
functions and intervention only needed for
complex functions. But the next level, full
automation, will come – where all functions are
automated and performance exceeds that of
manual and where the mine plan can be uploaded
to equipment and the mine plan execution is
carried out autonomously. How do you get to that
next step? Haukeness identified drivers like the
cost profile of manpower, high employee turnover,
infrastructure requirements, operating expenses,
need for higher productivity and continued safety
incidents; with key enabling factors including new
tech leveraged from other industries like
automotive, machine learning (AI) and edge
computing, new personnel skills acquisition (eg
operational automation specialists), a conducive
regulatory and political environment and last but
not least, standards-based interoperability and
infrastructure. Komatsu says safety is the number
one factor in AHS introduction for its customers
ahead of productivity.
So why is Komatsu making the case for private
LTE? Haukeness highlighted some of the earlier
points made by Jaime Laguna Ramirez – coverage,
capacity and latency – which meansfor some it is
now the preferred solution over WiFi. LTE usually
has much higher allowed output power, resulting
in a longer range. It also has lower frequency
bands, meaning signals travel further on the same
amount of power. It has licensed and coordinated
frequencies leading to less noise. As a result,
meeting AHS needs requires drastically less field
equipment to maintain in most cases.
Komatsu argues from a reliability standpoint,
the air interface with LTE is more reliable being
private, licensed and full duplex. It allows for the
notification of errored frames immediately to the
UE and scheduled re-broadcast. Less equipment
to maintain means better maintenance focus per
equipment and less work for field teams leading
to greater uptime, while reliability of message
delivery is orders of magnitude better on LTE
versus 802.11 WiFi. Looking at Quality of Service,
(QoS), this is a key enabler – full duplex
transmission and built in robust QoS mechanisms
lead to a dynamic shift in the capabilities of the
network. Sharing of connection leads to better
outcomes for mission critical applications when
compared to sharing the same workload on
traditional 802.11 WiFi systems. What does this
mean? In autonomous mine network is both a
process control and a process stop network.
Safety in the field is on one level dependent on
the network as it is delivering key messages to
trucks like stop or slow down.
With WiFi one client transmits at a time and if
two frames are sent at once, both are lost and
must retry. LTE divides up frequency and time with
the eNodeB deciding who each block is assigned
to – and UEs with high priority traffic get more
blocks when allowed. Multiple UEs can transmit
simultaneously. This all ensures critical network
traffic is delivered on time. Haukeness said that
looking at when Komatsu transitioned from WiFi to
LTE at its Arizona Proving Ground, on any given
day the WiFi packet loss was about 4%. While that
is a relatively good number, with LTE installed in
the first four hours of use the loss was minute –
about 4 packets of data.
What about use cases that illustrate the
importance of very high network reliability?
Collision Awareness Systems (CAS) is one
example. In CAS products, direct comms are
essential to the function but only provide half the
functionality that true Industry 4.0 needs, namely
direct, real time warnings, notifications and
communication of intents with limited range and
throughput. LTE provides a path back to the
servers, allowing for system login, reporting,
NLT reports growth with N-Connex solution
LTE still only represents a tiny part of the mining networks market. NLT Digital Solutions told IM
that it has seen significant growth over the past year in global mining and tunnelling markets. It
says its unique N-Connex platform which provides a fibre Gigabit backbone, Ethernet and Wifi
connectivity has ticked many boxes for its broad client base and combined with its software
applications resolves many typical mine issues in a very cost effective manner.
NLT states: "N-Connex is specifically designed for harsh environments, like underground mines.
The system is rapidly deployed due to its user-friendly rail based mounting system and modular
approach. Combined with pre-terminated fibre and ethernet cables a mine level can be quickly
deployed and importantly easily maintained thereafter. The IP67 rated modules do not require
additional enclosure or mounting hardware, so the solution is very scalable and easily expanded.
Another proven advantage is that installation and maintenance can be carried out non IT
specialists, for example mine electricians."
Being WiFi and Ethernet standards compliant, any supporting clients devices can easily connect
over the N-Connex system and NLT is seeing an expanded range of solutions from voice
communications to remote WiFi blasting being successfully deployed. Control and monitoring of
equipment such as fans and pumps has also grown in the past year with the ease of connecting
PLC’s to N-Connex. There is also a specific N-Connex digital or analogue I/O module to connect
equipment that does not currently have a PLC or connectivity. Additionally, tracking, data
communications, video monitoring, gas and environmental monitoring, emergency management
though the dedicated evacuation and alarm modules are all supported and implemented in many
mines.
In recent months Kirkland Lake Gold's Fosterville underground gold mine in Australia
commenced deployment of a large network with over 70 nodes and about 500 access points to
cover off the majority of their mine. In the USA, Martin Marietta’s Burning Springs underground
limestone mine is now doing
remote WiFi blasting over an N-
Connex network with Dyno Nobel
along with voice communications
and personnel/vehicle tracking. A
ventilation on
demand/optimisation solution for
a large tunnel project in Austria
(which will be the longest rail
tunnel in the world) has also been
rolled out this past year. Currently
NLT is also deploying a large
tracking system for Lundin Gold’s
Fruta del Norte mine in Ecuador on
NLT's unique N-Connex platform provides a fibre Gigabit
the back of a successful WiFi backbone, Ethernet and Wifi connectivity which has ticked
deployment early in 2020.
many boxes for its broad client base
30 International Mining | SEPTEMBER 2020