21 Jan Step it up a gear!
5 reasons why the robotics industry must get its teeth into innovation
Today I am going to tell you why I’m obsessed with gears. Yes, you heard me right. Gears! They occupy the majority of my waking hours. They keep me awake at night. And I am certain that they are the mechanical key to Industry 4.0. Gears.
Wille Wonka Wonderment
And before you stop reading, I want to take you back in time to a magical moment in your childhood….
Maybe you are about eight years old. And perhaps, like me, you are lucky enough to be given a new bike **with gears**. Tentatively, but beaming with pride, you set off on your new set of wheels. You experiment with cranking up a gear. Suddenly your pedal power is multiplied and you can keep up your friends around the neighbourhood (or farm tracks, in my case). You switch down to a low gear and you can finally pedal it up the hill, where you would normally have to get off and push.
Later, at home, you take the time to inspect this wondrous interplay of cogs and chains. Aged eight, gears represent mechanical magic. They afford you speed, power and freedom.
Fast-forward a few decades and the Willie Wonka wonderment you felt has – most likely – worn off. In the same categories as, say, wheels, gears are taken for granted. As a so-called simple machine, based on the principle of levers, they have been incorporated into hundreds of not-so-simple items in our everyday life, from cars to kitchen mixers. But we forget about them because they are usually hidden from view. It’s simply assumed that they are there. And that they work.
Yet, on the subject of gears, the engineering community has pretty much neglected to get into gear. Pardon the pun, but for last 60 years, we’ve just been merrily cruising along. Think about it: when was the last real breakthrough in gear technology?
Bruce Schena, ex-Google Robots engineer, can tell you the answer: “The overwhelming majority of robotic arms being sold today use technology that was invented in the same year that Sputnik was launched – 1957.”
What’s that I hear you say? If it it ain’t broke, don’t fix it? Well, gears may not be broken, but they sure are preventing us from realising our engineering ambitions. Smaller, lighter, more efficient, highly automated and affordable machines will not become commonplace without serious innovation in the field of gears. Not marginal improvements. But big leaps forward on what is technically possible, bringing five big benefits to robotics, clean energy and transport. Here they are:
- Strength & Dexterity
Gears in robots (or actuators, as they are known in the trade) are tasked with transforming high speed electrical input into useful torque, so that a robot can twist, lift, push, pull… essentially so that it can perform whatever action it has been programmed to do.
The gear ratio dictates conversion of speed to torque and ultimately, the strength of the robot. A ratio of 100:1 is typical, because that efficiently uses the total power of the electromotor for torque.
Ratios mean that robots are better able to swing their arms towards a target object, stretch out their grippers and manipulate an object with the desired level of strength and accuracy. Again and again and again.
While a glance at YouTube might give the uninitiated the idea that robots are already doing this on mass, in reality when it comes to robots the potential demand is largely untapped and will remain so until we get a grip on better gears.
- Precision & Safety
The robotic revolution is progressing in fits and starts. Much like robots themselves. And the cause of shaky process? You got it: gears!Traditional cogged gears suffer from backlash – a jolting that results from the play between the gear teeth and which can be seen playing out in the archetypal jerkiness of robots. And while these staccato movements are viewed as quintessentially robotic, the reality for those in the industry is that they are highly problematic. A robot which can’t place something on precisely the right spot, or which quivers when the emergency stop is applied is neither effective or safe.
While some gear manufacturers claim no backlash, the truth is that all gears with teeth suffer from the problem to a greater or lesser extent. Backlash is a key reason why Foxconn, Apple’s main contract manufacturer, still relies a human workforce to assemble the complex gadgets. And it’s also part of the reason why industrial robots are kept in cages.
Only through fundamental innovations in gears (such as getting rid of the teeth) will we be able to bid farewell to backlash and unleash the potential of industrial robotics.
Gears that rely on teeth impede the efficiency of their applications. Firstly, they require lubrication. In the case of industrial robots, this means stopping production for the messy business of oiling the actuators. In a typical car plant, the production line must shut down for nearly a year to service all the robots.
Secondly gears with teeth are bulky and rather heavy. Innovation leading to lighter, smaller gears would in turn, result in more nimble and efficient robots, which could make light work of the toughest of tasks, saving materials and energy.
- Healthy Supply
“According to a supply-chain bottleneck joke doing the rounds in the factory automation industry, it is now quicker to gestate a baby than secure a reduction gear from Harmonic Drive Systems” This was the opening line of a Financial Times article published in April 2018 – an amusing observation on the fact that demand for the best available actuators massively outstrips supply.
This is not only an indication of the growth in industrial robotics but a reflection on the artisanal mode of manufacture that the Japanese gear giant – Harmonic Drive – relies on. Bespoke designs and an accompanying complexity of production mean that the much respected just in time Japanese manufacturing model, might more accurately be described as “at some point in time….”
Innovation in gears would mean simpler and scalable assembly processes – afforded by revolutionary new designs.
- Accessible Price
If one of the things holding back the robotics revolution is the level of investment required, then addressing the price of gears is a crucial part of the puzzle.
A typical industrial robot contains six gears, while a complicated surgical robot contains more than 30, adding up to about a third of the hardware costs. But high performance gears shouldn’t have to be sold at such a premium. Find a way to make them stronger, smaller, lighter and easier to make and then a more accessible price should follow through.
So there you have it. Five reasons why innovation in gears is crucial for better performing, more easily available and more affordable robots. And five reasons why me and my talented team of engineers at IMSystems, spend our days (and nights) working to get the Archimedes Drive – our toothless gearbox – into manufacture.
 ‘Should you invest in Japan’s robotmakers?’ – Leo Lewis, Financial Times, 9h April 2018