Thermal Camera update: new brand, new form factor with thermal reference.
It's been interesting watching New Zealand's changing attitude towards COVID-19 as we've gone through different stages. From extreme caution during the lockdown to (somewhat justifiable) complacency when we got our cases to 0. To renewed caution when when we started finding infected people at the boarder. To now, where we probably have too much complacency reflected by lack of people willing to be tested. We're all watching what's happening in Victoria and other parts of the world, thankful for the situation that we're in and hopeful that it won't happen to us.
The development of our thermal camera to detect people with fevers has somewhat followed our changing attitude towards COVID-19. We were building cameras and developing the software as quickly as possible during the lockdown, working nights and weekends. Once we were at level one the team started working at a more sustainable pace and even took a few holidays. I've been overdue to give an update, with the last one back in May. Despite the lack of communication we have been working on the project and will continue to do so, with the backing of a government grant.
Thermal reference gives good accuracy
We have successfully integrated our thermal reference into the camera and are now getting reliable temperature readings without the need for frequent calibrations.
The thermal reference is simply a small box that contains a metal plate that heats up to a constant temperature. This thermal reference sits in the field of view of the camera and the people are then compared to this to calculate an accurate estimate of forehead temperature and an estimate of core body temperature from that.
Our early customers have found that this has worked much more reliably and are now testing everyone that comes in and out of their organisations.
This thermal reference was developed by the University of Canterbury during the lock down and they kindly donated all the intellectual property to the open source project. We have now manufacturing these thermal references in Christchurch and continuing to improve the design.
New form factor
With the thermal reference we had the camera measuring temperatures reliably, but our physical set up was still a little "clunky". We had the camera and thermal reference on tripods, with a tablet floating around. While accurate it was a mess of tripods and cables.
Enter Lincoln Sell - former CEO of YikeBike and mechanical engineer who has been employed by Cacophony to work on the mechanical parts of the project - like the trap design (more on that later over on the Cacophony and 2040 blogs).
Lincoln designed a new enclosure for the camera that holds the screen and has an arm holding the thermal reference. Another engineer has redesigned the electronics so we only need one power cable. This can easily be mounted on a tripod, or a wall. We've also made it so the display works via a cable rather than WiFi, improving the reliability. The arm can be mounted on either side of the camera depending on what works best for you.
The end result is a lot less clunky. We are continuing to improve on the design and have started manufacturing these cameras. All existing customers will be offered an upgrade.
In order to separate the fever detection from our predator control products we have introduced the Te Kahu Ora brand and this website.
Evaluating other cameras
Not wanting to re-invent the wheel, we have evaluated other cameras to see whether we could use their hardware and test some of our innovative ideas. We got close, but failed to find any that had the resolution, open interfaces and reasonable price point that we required.
We have introduced a new way of updating our software that should be more reliable. We have found that some customers' networks prevented our previous update method from working.
After observing that some customers turned the sound down on their devices we have removed the sound that used to play when a person was detected with a safe temperature. We will make this optional in a future release. For now the device will only play a sound when a person is detected with an elevated temperature.
Upcoming software releases
We are about to start testing a new interface that identifies that a person is in the frame, finds their forehead and then logs their temperature to the cloud. This will provide another accuracy improvement, by reliably taking the forehead temperature, rather than the hottest spot. It will also mean we will be much less likely to trigger on something else hot in the frame of the camera.
This is a proof of concept showing the new interface.
We have observed customers who manually write down the temperature of each person that is scanned for their own records. This new feature recording the temperatures to the cloud will allow us to provide all this data via a log-in on the Te Kahu Ora site.
Finally we have produced an updated manual for the new camera.