The search for ultra-low cost IoT: How low can we go?

May 01, 2017

Rob Milner-May 01, 2017

With Gartner forecasting 21 billion IoT devices by 2020, and Softbank predicting a coming “Cambrian explosion” of IoT connectivity, the bar has been set high. But there are mountains to be moved before such lofty predictions can be realized.

Even a few cents is too much to add connectivity to low-value devices. I’ve come to believe that we must reduce the cost of connectivity far below today’s levels to enable IoT to grow exponentially. This will, in turn, require radical simplicity. Anyone who’s used one of Amazon’s Dash buttons to re-order a consumable will have a sense of how simple connected devices are becoming.

A ruthless optimization aimed at stripping out cost leaves us with a minimum viable IoT device that requires just power, connectivity, sensing and cloud. Here’s how I see that:

Connectivity should be based on technologies in smartphones in order to use that phone as a gateway and to remove infrastructure costs. It should also have range – a bubble of connectivity – to avoid needing user actions to enable the connectivity. We also expect that a small part of the resources needed for the connectivity would be made available for applications processing.

Sensing in a minimum viable IoT device will be simple: Think of sensors such as a trace on a circuit that gets broken or an integrated temperature sensor.

For power, we found it hard to get away from a device that is permanently powered. Power is needed for the connectivity and makes the sensing information that can be collected massively more valuable – not just because you can sense the whole time, but because power also allows you to determine when something has happened.

It’s clear then that we’re describing a device that isn’t based on RFID or NFC – mainly because we view these as limited by the need for specialist infrastructure, user interaction and incomplete phone adoption.

Where are we now?

Some of the elements of a radically simple, low cost IoT device have already arrived.

First, let’s look at the Bluetooth Beacon formats that have arrived in recent years. Having assessed each of the viable contenders, I’m firmly a supporter of Google’s Eddystone format as an enabler of ultra-low cost IoT. Here’s how it works: data is encrypted in beacon adverts that are heard by phones. If it’s an Android phone it doesn’t even need to have an app installed, only for Google’s nearby services to be enabled. When the phone hears a new advert it forwards it to a resolving service in the cloud that decrypts that payload. This means that the information created by the infrastructure, and the revenue associated with it, are protected. In short then, an architecture such as Eddystone turns all phones into IoT gateways and enables monetization in the cloud.

But today’s Beacon implementations will be hampered by price: with cost still related to the area of silicon, the biggest single component cost will be the Bluetooth chip. Designed to reduce that dependency, all-digital radio technology such as our own Pizzicato technology removes all analog components on a silicon radio, enabling the radio to overcome today’s physical barriers. These radio technologies also directly benefit from Moore’s Law’s with further reductions in size, cost and power consumption with each new generation. Pizzicato has enabled us to demonstrate a seven-cent Bluetooth radio – a new benchmark in low cost IoT, but a price point that we believe can and will be further reduced.

Going further

Having addressed the most expensive component, we then need to look at the whole device in order to further simplify and strip out cost.

Complexity is a problem. An increase in the number of parts ripples through manufacturing – increasing assembly costs, the number assembly stages, parts inventories, and so on.

Work needs to focus on all the parts that go into a device and why they’re needed. For example, a core stage in stripping out components is achieved by moving from designing the battery into a product to instead designing the product into the battery. For example, we have identified injection moldable plastics that are compatible with proven battery systems: both the major substances and their various by-products (in fact some materials such as polyimides, which can be used to define circuits, are already used within some batteries).

This shift means that we can create low cost devices that are made using existing high volume production techniques, but which also reduce the number of assembly steps and consolidate the number of components. The 3D schematic below shows the idea.


 

Here, the battery becomes a void in the primary casing into which the PCB is assembled, while the contacts become areas defined on the PCB. The product casing is the primary electrolyte holder.

At this point, this vision of ultra-low cost IoT looks strong, but this approach brings a major problem: Billions of tiny batteries in disposable devices are a chemical pollution disaster, and will the growth of the electric vehicle market grab the world’s supply of Lithium? Is there’s a more organic approach?

Perhaps you’ve heard of the researchers that have turned clams into batteries. Cyborg clams may be some way off, but work on bio batteries, or more properly, Enzymatic Fuel Cells is progressing – this work effectively reproduces the reactions taking place in living organisms that generate electricity, and duplicates them outside of the cell. There are many research groups looking at this with several lines of attack, but there’s a trend that gives us cause for optimism.

The following graph is the biotech equivalent to Moore’s Law, showing the cost of sequencing DNA.


 

The graph is logarithmic (which is why Moore’s Law appears as a straight line) and whilst all areas of biotech won’t follow this curve, it does give a good feeling for the pace of development. This rapid progress is one of the reasons that we set up our own synthetic biology lab last year.

Research groups are reporting shelf lives and operational lives of bio batteries measured in months and heading towards a year. From a cost perspective, there is research suggesting an enzyme cost of six cents for a bio battery.

The business model

We’ve been taking a ruthless view on reducing cost, which is helpful for reducing the bottom line, but what about the return? This question comes into sharp relief for anyone in the value chain who has previously made money with a margin on components.

The key shift in approach is to realize revenue from all touchpoints through the device’s life. I’ve suggested that we imagine a bubble around all connected ‘things’ within which they can use a phone as a gateway. Now, even simple sensing can generate valuable business. Think for example, of an IoT beer bottle, which can be monitored through its life from manufacture, bottling, distribution, retail, consumer and recycling, delivering small packets of value at each stage. This might relate to temperature sensing, anti-tamper through track breaking, liquid level sensing, maximizing recycle rates, and more. In retail, this technology could be used to turn any item of consumer goods into a data platform, and transform the market research industry by solving problems such as limited scalability, sample bias, and reliance on stated rather than observed data. These data feeds would be near real time, allowing business to react quickly to any changing trends.

Now, the Amazon Dash-style replenish button is merely one of many stages delivering value in the life of a product.

This is just a small insight into our own current work and thoughts for the future. It’s inevitably a mix of the technologies on today’s bleeding edge, and speculations for the future. However, we’re optimistic, seeing a range of technologies just over the horizon that will strip out cost and ensure that IoT really does represent the “Cambrian explosion” of connectivity that the industry seeks. 

Rob Milner is Head of Connectivity at Cambridge Consultants, a product development firm and the world’s largest independent wireless development group. As the senior technical architect and leader for Cambridge Consultants’ smart systems work, Rob works on connected system development projects that deliver new product and service opportunities for clients. Rob specialises in short range wireless technologies and IoT, where he is an acknowledged visionary.

 

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