Bluetooth iBeacons are increasingly being used with fleet tracking. An example is Geotab who claim to be:
“World’s leading connected vehicle company, helping businesses leverage data to better manage and track their fleet”.
GeoTab has IoX extensions that extend the capabilities of their system.
IOX-BT
One such extension is IOX-BT which monitors beacons attached to tools and equipment. This allows the system to be used to improve asset utilisation, reduce misplaced equipment, boost productivity, reduce operational costs and improve on-time delivery.
There’s lots said about the advantages of Industry 4.0 or Digital Transformation and the associated new technologies but it’s a lot harder to apply this to the context of a business that has legacy equipment and no real way of knowing where to start.
Our previous article on productivity explained how, historically, digital transformation has been only been implemented in the top 5% ‘frontier’ companies. These have tended to be very large companies with large R&D budgets that have enabled customised digital solutions. More recently, the availability of less expensive sensors and software components have extended opportunities to the SME companies. These companies are already realising gains in profitability, customer experience and operational efficiency. Unlike previous technologies, such as CRM, the newer technologies such as IoT and AI are more transformative. Companies that don’t update their processes risk being outranked by their competition with a greater possibility of going out of business. But where do you start?
The place to start is not technology but instead something you and your colleagues fortunately have lots of experience of : Your company. Take an honest look at your processes and work out the key problems that, if solved, would achieve the greatest gains. You might have ignored problems or inefficiencies for years or decades because they were thought to be insolvable. Technology might now be able to solve some of these problems. So what kind of problems? Think in terms of bottlenecks, costly workrounds, human effort-limited tasks, stoppages, downtimes, process delays, under-used equipment and even under-used people. Can you measure these things and react? Can you predict they are about to happen? This is where sensing comes in.
The next stage is connectivity. You will almost certainly need to upgrade or expand your WiFi and/or Ethernet network. It can be impractical to put sensors on everything and everyone and connect everything by WiFi/Ethernet. Instead, consider Bluetooth LE and sensor beacons to provide a low cost, low power solution for the last 50 to 100m. Bluetooth mesh can provide site-wide connectivity.
Initially implement a few key improvements that offer good payback for the effort (ROI). The improvements in efficiency, productivity, reduced costs and even customer experience should be enough to convince stakeholders to expand and better plan the digital transformation. This involves replacement of inefficient equipment and inefficient processes using, for example, robotics and 3D printing. It also involves analysing higher order information combined from multiple sources and using more advanced techniques such as AI machine learning to recognise and detect patterns to detect, classify and predict. This solves problem complexity beyond that able to be solved by the human mind or algorithmic program created by a programmer.
Tracking loaded pallets saves a significant amount of time, effort and hence cost in logistics and manufacturing. Pallets might contain stock, components or sub-assemblies. The top usecase is finding a particular pallet quickly. However, sensing need not be limited to pallets. Extending tracking to forklifts, racking and even people provides additional business benefits. For example, we have previously been asked to provide for the following scenarios:
“I need to ensure best use of my forklifts. Tell me when one hasn’t moved for 2 minutes.”
“I need to know if a forklift has crashed into racking.”
“I run a warehouse containing hazardous materials. If evacuation is needed, I need to know everyone has evacuated the building even if someone has temporarily gone off site”
These situations, and more, are solvable using Bluetooth beacons (In terms of asset tracking, beacons are sometimes called tags).
RFID and barcodes can also be used for tracking. However, the information is only as good as the last scan that might have been a long time ago after which the asset might have moved without being scanned. The advantage of beacons is that they repeatedly advertise so the information is always up to date.
Further advantages of Bluetooth tags are:
Being commodity items rather than specialist devices, tags and readers are relatively inexpensive compared to other proprietary technologies such as ultra wideband (UWB).
They consume very low power and battery lifetimes of 5 to 10 years are possible.
They are readable from handheld devices such as smartphones and tablets, providing for additional possibilities within the warehouse.
Software such as our BeaconServer™ and BeaconRTLS™ can be used to track what’s where over time, create notifications and integrate with your existing systems.
Once you have some current and historical data you can also start to do clever things such as automatically detecting and predicting over or under utilisation, finding pinch points or detecting valuable equipment about to be stolen.
Connected factory implementations require a large number of connected assets for condition-based monitoring, asset tracking, inventory (stock) management or for building automation. Bluetooth is a secure, low cost, low power and reliable solution suitable for use in connected factories. In this post, we examine the reasoning behind some out-of-date thinking on industrial wireless, uncover the real problems in factories and provide some explanations how Bluetooth overcomes these challenges.
Operations teams are usually very sceptical about industrial wireless. They have usually tried proprietary industry solutions using wireless with mixed results. They might have experienced how connections, such as WiFi, can become unreliable in the more electrically noisy areas of factories. The usual approach is to use cable. However, this can become expensive and time consuming. Using cable isn’t possible when assets are moving and becomes impractical when the number of connected items becomes large as in the case of connected factories. As we shall explain, Bluetooth is intrinsically more reliable than WiFi even through they share the same 2.4GHz frequency band.
There’s usually lots of electrical noise in an industrial environment that tends to be one of two types:
Electromagnetic radiation emitted by equipment. This typically includes engines, charging devices, frequency converters, power converters and welding. It also includes transmissions from other radio equipment such as DECT phones and mobile telephones.
Multipath propagation which is reflection of radio signals off, usually metallic, surfaces and received again slightly later.
It’s important to understand how Bluetooth and other competing technologies react to these types of interference. There’s a useful study (pdf) by Linköping University, Swedish Defence Research Agency (FOI) and the University of Gävle on noise industrial environments.
Noise in industrial environments tends to follow the following spectral pattern:
Electrical noise spectrum
There’s usually lots of electrical noise up to about 500MHz. This means wireless communication using lower frequencies, such as two way radio, exhibits a lot of noise. Pertinently, several wireless solutions for industrial applications use frequencies in the 30–80 MHz and 400–450 MHz bands. Bluetooth’s and WiFi’s 2.4GHz frequency is well above 500MHz so exhibits better reliability than some industrial wireless solutions. Incidentally, in the above charts, the peaks around 900 MHz and 1800 MHz mobile phone signals and 1880–1890 MHz come from DECT phones.
The magnitude of multipath propoagation depends on the environment. It’s greatest in buildings having highly reflective, usually metallic, floors, walls and roofs. If you imagine a radio signal wave being received and then received again nanoseconds later, you can imagine how both the amplitude (peaks) and the phase of the received signal becomes distorted over time. Bluetooth uses Adaptive Frequency Hopping (AFH) which means that packets transferred consecutively in time do not use the same frequency. Thus each packet acts like a single narrowband transmission and there’s less affect of one packet on the next one. However, what is more affected is amplitude which manifests itself as the received overall signal strength (RSSI). RSSI is often used by Bluetooth applications to infer distance from sender to receiver. We will mention mitigations for varying RSSI later.
It’s important to consider what happens when there is electrical noise. It turns out that technologies invented to ensure reliable transmission behave much less well in noisy situations. One such technique is carrier sense multiple access (CSMA), used by WLAN (WiFi), that listens to the channel before transmitting and waits until a free channel is observed. CSMA and automatic auto repeat (ARQ) also have re-transmission mechanisms. The retrying can also incur significant extra traffic that can overwhelm the communication in noisy environment. Bluetooth doesn’t use such schemes.
The previously mentioned research classifies different wireless technologies according to the delay when used in noisy environments:
Bluetooth (and WISA) is a good choice for noisier environments. It’s particularly suited for applications with lower data rates and sending at periodic intervals.
A final consideration is interference between Bluetooth and other technologies, such as WiFi, that use similar 2.4GHz frequencies. As mentioned in a previous post, there’s negligible overlap between Bluetooth and WiFi channel frequencies.
In summary, Bluetooth is more suited to electrically noisy environments and also offers low cost, low power and secure wireless communication.
These conclusions correlate well with our own empirical observations. We have found that Bluetooth advertising is still received in environments we have measured, using a RF spectrum analyser, to be electrically noisy around 2.4GHz . We believe this is because Bluetooth advertising hops across three frequencies such that there’s less likelihood of noise on all three. Advertising is also very short, typically taking 1 or 2 ms, making the coincidence of the noise and the advertising less likely than would be the case of a longer transmission.
It has been our experience that solutions using Bluetooth advertising are more reliable than those using Bluetooth (GATT) connections, especially in noisy environments when it’s difficult to maintain the chatty protocol of a connection over a long time period. In noisy situations, advertising is usually seen on a future transmit/scan if the first advertising is lost. By coincidence or design, Bluetooth Mesh is built on communication via advertising rather than connection and for this reason is also reliable on the factory floor.
However, using Bluetooth isn’t a silver bullet. There are situations where factories, or more usually parts of factories, have reflective surfaces or unusual radio frequency (RF) characteristics stretching into unforeseen frequencies. Poorer performing WiFi also needs to be considered in context of choosing between Ethernet and WiFi gateways and Bluetooth mesh.
It’s important to do a site survey including RF spectral analysis. This will uncover nuances of particular critical locations or coverage that can drive subsequent hardware planning. It can also feed into requirements for software processing, for example particular settings for processing within a real time locating system (RTLS) to cater for more varying RSSI.
The traditional way of tracking assets using barcodes, NFC or RFID requires that someone of something scan the items at very close range. Bluetooth has the advantage that it works up to 70m, sometimes up to 300m allowing the reading to be done:
Without moving the items, saving infrastructure such as conveyor belts
Without human involvement, saving time
Continuously
The affect of ‘continuously’ is subtle but powerful. With traditional scanning, information as to the whereabouts of an item is only as good as the last scan that could be minutes, hours or even days ago. If the item moves without scanning, finding it can be very difficult. Bluetooth asset tracking is updated continuously.
Although beacons cost more than barcodes, NFC and RFID, the readers, usually gateways, cost considerably (x10) less. As the beacons are Bluetooth, for some scenarios the readers are ‘free’ as you can use smartphones already in use. Nevertheless, beacons cost ($5 to $40) more than barcodes so tend to be used on aggregated items such as pallets and sub-assemblies or on single valuable items.
Beacons go beyond simple simple assets tracking into the Internet of Things (IoT). The same beacons can monitor quantities such as vibration, temperature, humidity, light, proximity, smoke and gas. Using beacons for extra purposes such as sensing and providing triggered information about assets can often be the most compelling aspect of using beacons.
When it comes to software, think carefully. Most people expect functionality similar to traditional barcode-based asset tracking with software on a server somewhere. While the equivalent exists in the form of RTLS systems that put beacons onto maps and plans, it’s sometimes possible to implement a simpler solution to get the job done. Could your requirements be met with just an app? One such example is the work we did for Malvern instruments that’s a simple app that does a stock check by scanning for beacons as the user moves about their site. Also, we have found that many organisations don’t actually need a full asset management solution but instead need something that can capture beacon data and make it available to their existing systems. Our BeaconServer™ fulfils that role.
Tracking things and/or people makes organisations more efficient through enhanced productivity. Most organisations want to improve a specific problem in one of the following areas:
Stock Control – Knowing how much you have, where, without any human checking
Finding Items – Picking items without time-consuming manual searching
Safety & Security – Knowing when assets move, go missing, are dropped or crashed into
Process Efficiency – Preventing human error of manual audits, knowing an expensive asset is being fully utilised, providing real time workplace instructions
Having solved a problem, it’s often the case that the act of digitisation allows other problems to be identified and also solved.
There are many ways to track assets using beacons. Beacons can be put on assets and detected by smartphones, Bluetooth gateways, Bluetooth mesh, or other Bluetooth LE devices such as single board computers. Alternatively, beacons can be fixed and the detecting device(s) can move. Software can be in the detecting devices and/or at a server receiving data from the detecting devices. It’s also possible to use a real time locating system (RTLS) to map the positions of assets.
The optimum solution depends on your situation and requirements. Here are some aspects to think about that will determine the optimum solution:
What’s the size of area(s) and sub-areas (rooms, zones) you need to cover and is this outside?
What’s the physical makeup of the areas (walls, racking) and their composition?
What’s the electrical infrastructure (power, WiFi and Ethernet availability) and can this be upgraded?
What assets need to be tracked?
What attributes of assets need to be tracked (just location or sensor data as well?)
How many need to be tracked?
How many are in the same place, at the same time?
How often do the assets move?
How accurate do you need the locating?
How up to date do you need the tracking?
Who needs to do the tracking, from where?
How many people need to do the tracking simultaneously?
What kinds of information/report do you require and what’s the desired method of receiving?
We mentioned Wiliot last March and since then their R&D team has created early engineering samples that prove it’s possible to create a battery-less Bluetooth LE beacon harvesting energy from radio frequencies (RF).
The Wiliot device looks more like a RFID tag than a traditional beacon in that it’s supplied as a very thin PVC inlay sheet containing the chip and wire antenna together. The thin form factor, no battery and the relatively low cost will allow it to be manufactured into or stuck onto clothing and packaging that will provide for many new usecases.
Producing such a device isn’t easy as it can’t use existing System On a Chip (SoC) devices as produced by Nordic, Dialog and Texas Instruments (TI) because they are too large and use too much power. Wiliot has had to create their own SoC from the ground up, including software tools to develop and program the devices. We have been told it will be a year before Wilot has all the components in place for commercial rollout. Meanwhile, selected organisations can join the Early Advantage Program (EAP). There’s a new a product overview (PDF below) that explains the EAP and the main usecases, connected packaging, connected apparel, logistics and asset tracking:
Wiliot already have Early Advantage Program (EAP) agreements in place with over a dozen brands including top fashion brands, a telco, appliance companies, a furniture brand and packaging companies.
It starts with a discussion that tries to define what’s a Real Time Location System (RTLS) in terms of the technologies that can be used. Ajay explains how he ended up working with RTLS and writing the book.
There’s discussion on business drivers and how RTLS relates to machine to machine (M2M) and IoT. Usecases mentioned include promotional marketing, asset tracking and autonomous navigation. There’s a useful explanation of trilateration, triangulation, angle of arrival, time of arrival and time distance of arrival.
Ajay sees asset tracking as currently the most important application. However, going forward, RTLS will feed more into AI to provide context.
Proximity.directory has a new report on the State Of The Proximity & Location Industry. It’s great to see proximity.directory reports moving beyond retail marketing into asset tracking.
The report gives a great overview of how asset tracking works, the benefits, provides some case studies and lots of charts.
“Hospitals can save hundreds of
thousands dollars a year with an
immediate ROI of 275%”
The majority of beacon-based solutions are app-based and trigger information to be displayed to the user in response to being near specific beacons. If you read many platform provider sites you might think that’s all beacons can do. However, beacons are a technology and not solution. Beacons provide for many types of solution.
Another type of solution is the accounting for things (with beacons attached) within a larger system. Examples include class registration, stock checking, asset tracking, security and lone worker positioning. In these cases the thing that detects beacons can be can be an app or hardware.
The app can be relatively simple and scan for particular beacons and save information to a file and/or send them on to server. We recently implemented such a system for Malvern Instruments, with custom pre-configured beacons, that also allows search for particular ‘lost’ beacons:
In the cases where the beacon detection doesn’t or shouldn’t move around, it’s possible to use gateways to forward on detected beacon data to a server.
IGS01 Wifi Beacon Gateway
Several of our clients are using this type of architecture to provide for automatic human registration/rollcall type solutions.
We believe even greater opportunities exist for IoT scenarios where sensor data in beacon advertising can be automatically forwarded on to servers.
