Open Pit Wireless Networking Basics
I must start this blogpost by apologizing for my absence during the past few months. However, today I bring you a piece that I hope will be handy to those working in the mining industry who do not pose any background training in wireless networking. Successful deployment of a wireless network at a mine with large moving equipment over a sizeable coverage area is not as simple as traditional wireless deployments, with primarily fixed equipment (I.e. Processing or manufacturing plant).
When I went into the Mining Engineering & Mineral Processing program at UBC (University of British Columbia), everyone outside of mining warned me how narrow that was, how it would limit my opportunities and that I would be stuck in a niche. However, upon further investigation I found out it was quite the contrary. I had classes in Civil Engineering, Mechanical Engineering (Oh Bernoulli – good times), Earth & Ocean Sciences, and Electrical Engineering; plus all the Arts electives.
After getting out in the field, I discovered that, in order to do our jobs well, not only did we need a basic understanding of all the different engineering disciplines named above, but also knowledge of areas such as the following, but not limited to: heavy mobile equipment, maintenance engineering, contract management, tax laws, technology and IT/IS (Information Technology/Information Systems). For example, you would need to be familiar with how to find and how to apply local tax rules on economic evaluations. As a side note, Colorado School of Mines offers a program, “Economic Evaluation and Investment Decision Methods”, great for engineers who are making capital allocation recommendations and need to calculate true ROI (Return on Investment).
Those of you who know me know that one of my passions within the industry is with the utilizing of technologies to improve our productivity and safety within open pit mining operations and mobile equipment. One area that’s often taken for granted but is the platform, which enables all these new technologies, is robust & reliable wireless networking. Ever since I joined 3D-P – a company that specializes in wireless networking in the mining industry – in March 2011, I have realized how crucial and difficult it is to deploy and maintain a successful wireless network that supports not only day to day operations but also any continuous improvement projects.
We implement all these fancy new gadgets in the field (fuel monitoring, oil analysis, fleet management systems, collision avoidance, the list goes on…) so that we can make better decisions, closer to real time. We rely on a communications path from the mobile equipment back to the office, where the data can then be processed and an action item can be created for the operations team to act on. Only then and only then does the system start to pay for itself.
The main pitfalls of a wireless infrastructure in an open pit environment are as follows:
- Poor design resulting in “black holes” – areas where the piece of mobile equipment loses coverage
- Inadequate coverage – mines expand and the infrastructure doesn’t expand with it
- Low Reliability – Equipment that is purchased has a high failure rate or cannot withstand the rugged nature of mining
- Inadequate throughput – The type of radio selected for the mine is not enough for the mine management applications’ bandwidth requirements; this can happen as a mine starts adding applications onto a 10 year old network without considering upgrading the network. This can also result in delays in data movement (not real time anymore).
- Ownership – the wireless system at a mine could fall under any department ranging from Engineering to Dispatch to Operations to IT. Without strict accountabilities in place, the network does not receive the maintenance it needs. For example, as a mine expands, roads move, dump sites change, etc.
- Broken Connections – As the client (ie. Mobile equipment) moves around in the mine, it should always be looking for new connections and making new connections before it breaks the old one. This transition between old connection to new connection is called “handoff time.” Some wireless options have a higher handoff time than others. High handoff times could result in data packet losses.
What I am presenting below are the basic components of a typical infrastructure set-up. There are always exceptions of the rule but the following represents the majority of how what each layer is and what function it performs:
- Backbone – This is the first component of a communications platform. True backbone is via a copper/fiber cable connection; however, if there is no copper/fiber then a Point-To-Point radio will serve as the backbone, plugging directly into the server. This is not a common occurrence. For more info on the backbone, please visit Wikipedia here.
- Backhaul – This is the first piece of your wireless infrastructure, connected to the wired network (using a fiber, cable or copper connection) via a managed distribution switch. This layer is the link between the wired interface and smaller sub-networks. The switch, also referred to as a multi-port network bridge, is generally configured and installed by the wired network vendor or department. On a mine site, the backhaul is in the form of Point to Point or Point to Multi-Point radios, usually located at the main communications tower (A PTP radio is dedicated while a PTMP radio is shared.) For more info on the backhaul, please visit Wikipedia here.
- Distribution Layer – This layer further distributes the backhaul into smaller sizes. The distribution layer is usually in the form of a Point to Multi-Point (shared) radio, or it could be a part of an Access Point (functionality dependent). For example, in the new Motorola 7181 Access point, the 5.8GHz Meshconnex (infrastructure meshing) performs the distribution function and then 2.4GHz band acts as the access layer, discussed in the point below.
- Client Access Layer – This layer is the final layer providing wireless coverage to the end user. The access points are placed in active mining areas, all of which have a connection to the backhaul either via a wireless or a wired interface. A “repeater” is generally referred to as a client access point without a direct connection to the outer layers (ie. it utilizes another access point to connect to the distribution layer).
- Client Layer – The client layer represents the users of the network and the hardware that the person or piece of equipment needs to be outfitted with in order to access the network. Most commonly on a mine site, this would be heavy mobile equipment and sometimes light vehicles. This hardware is often the piece that you run your applications on. For example, you may have a radio card within your fleet management system hardware box. Or you could have a separate managed platform that you run multiple applications on. Or it could be a simple as a tablet or laptop running off the access point’s hotspot feature (if it is a WIFI network, ie. 802.11n).
It is important to note that garbage in… garbage out…, meaning if you feed your post-processing software corrupted data, as a result of an unreliable network, then you are making decisions incorrectly. Then all those millions of dollars you invested into new technologies, which rely on a real time connection, will not achieve the payback that you promised when you put together your cost benefit analysis. Remember: Data –> Report –> Action –> Payback. You need a solid comms network to credibly and reliably get from Data to Report. Then from Report to Action, it’s more about “change/transition management” (ie. creating/adjusting process, building SOPs, training the workforce, helping them want to change as opposed to feel like they are forced to change, etc.)
As you continue to work on projects involving productivity and safety, I urge you to audit your wireless network and perform a gap analysis of the network you have now and what you need or will need to sustain future growth and addition of new projects and technology enhancements.
Lastly, I would like to thank Trevor Williams, my colleague at 3D-P, for proof-reading my blogpost. Trevor, like me, comes from the mine operator side and understands and appreciates the struggles that a lot of mines experience. If you have any questions regarding this topic or any other technology/equipment questions, please do not hesitate to reach out.