Breeze Mode explained: how Dyson engineers recreated a natural breeze, indoors
How do you recreate the beauty of a natural breeze indoors? We catch up with Associate Principal Engineer Tim Jukes on how 40 million data points, eight locations and one algorithm created the Breeze Mode function on the Dyson Pure Humidify+Cool.
17 August 2020
Where did the idea for Breeze Mode come from?
The concept stems from the idea that people are more comfortable when they're in more natural environments. We're all animals at the end of the day and we are used to living outdoors, biologically and evolutionary speaking, and there's a lot of dynamics to that environment.
If you think about the wind itself, it's never steady, right? It's never just blowing constantly. And actually, it's never off either. So, these dynamics are part of our biology and our physiology. They're part of what we need and what we're used to, and what makes us comfortable - what makes us happy.
This is something that's termed 'allesthesia' and there are lots of different types of it. Allaesthesia is the term to describe the positive sensation you get when a need is fulfilled. For example, if you're really, really thirsty, and you have a drink of water, that water tastes phenomenal. So, the same happens in thermal comfort as well. When you're hot, and you get that nice, cool breeze, you feel a refreshing sensation, that really nice, pleasurable breeze.
In the context of the wind, people have found that by subjecting people to an airflow that's changing all of the time, people can be more comfortable and have a more pleasurable experience than if that flow is just on them constantly.
Ok, so how do you go about measuring a breeze?
The first thing we did was spend most of the summer of 2017 with an anemometer, at various sites around the Malmesbury campus. We deliberately made sure the study was different from other meteorological work, which normally measures the wind at 10 m from the ground. We, of course, we were interested in the human experience, so we were always recording it at human head height. Actually, the wind is quite different at those two locations because of the effect of the ground in close proximity.
So, we took about 200 hours’ worth of data, on different days, in different wind conditions, at different locations around the site and built a sizable database of what the wind is doing in summer in the UK. Well, specifically Cotswold wind!
When you take into account those different wind speeds on those different days, you find that the dynamic characteristics - or the turbulence - in wind is fairly universal.
Once you had an idea of what a typical breeze 'feels like' what came next?
The next phase of the experiment was to recreate it. The product was still far from finalised at that stage, but we had developed steerable jets to channel the airflow. We took the same equipment we were using to study the wind outside, brought that back inside into the laboratory, and started playing around with different algorithms to move these motors around in order to replicate the breeze.
We programmed algorithms into the stepper motors that move these jets side to side, and we programmed some randomness into that motion. After making little tweaks here or there, we were very close to replicating the same characteristics of what you get outside.
So how does it mechanically recreate the breeze and what so special about it?
The fact that you've got two jets gives an extra dimension. You might be getting hit from one jet slowly, while the other jet is hitting you quickly, so, you end up with a very wide spectrum of sensation from this device.
There are other fans who have done this in the past but it's the way we do it is unique. The fact that we do it by moving two jets, means we can push air out over a wide area but also, because we are moving these jets passed people, you do get those extra dynamics to it.
This is a really good example of fundamental research that we do in Dyson, and how that fundamental research builds into the whole development story. We really did start with quite basic research into the wind here and then got into the nitty-gritty of it, looking at the turbulence at quite a significant level. Then, we implemented that into a product, that gives a user a benefit at the end of it. It's something we're particularly proud of here.
1 Robert, J.W. et al. (2009) Monitoring and reducing exposure of infants to pollutants in house dust, Revue of Environmental Contamination and Toxicology, 201:1-39. Available at: https://www.ncbi.nlm.nih.gov/pubmed/19484587
2 Dunn, R.R. (2013) Home Life: Factors Structuring the Bacterial Diversity Found within and between Homes, PLOS. Available at: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.006413
Barberán, A. et al. (2015) The ecology of microscopic life in household dust, The Royal Society: Biological Sciences. Available at: https://royalsocietypublishing.org/doi/full/10.1098/rspb.2015.1139