It’s been a while! Please spend a few minutes reading this update.
Disclaimer: This is a formal update intended to update our backers about our technical development and fulfillment of the TZOA Research Devices. We will not get to the developments of the “enviro-tracker” and how excited we are about making a product that can benefit everyone // solve air quality issues; that will be a separate update soon!
TZOA has progressed significantly since our Indiegogo campaign was successfully funded 2 months ago on June 18th, 2015. Our focus post-campaign was late-September fulfillment of the ‘version 2.0’ TZOA Research Devices (RD02). Fortunately, our less expensive “enviro-tracker” uses the same technology as the research device, so the progress made contributes directly to the enviro-tracker’s progress. These two products develop in a linear fashion rather than in parallel.
As a company, our initial focus was to create products that contain an accurate air quality sensing technology, an innovative new technology we have developed that is both miniature and affordable. This is important because it results in useful products that can recommend actionable ‘air advice’ and also has the ability to evaluate the efficacy of different solutions for air pollution issues.
Before our IGG campaign began, we had a fully functional first version of the TZOA Research Device (RD01) containing our air quality sensing technology. We sent units out to be evaluated or included in projects, for example, to the University of British Columbia for a study in India – as well as other reputable organizations.
At the start of the IGG campaign, we had done a 3rd party evaluation of our proprietary air quality sensor technology for detecting particles (PM2.5/10). We correlated our sensor to a $9000 TSI DustTrak DRX research grade sensor and verified an R-squared value of .75 (linear regression) with .95 being the theoretical max, .95 representing a near-perfect correlation. We had advanced so quickly that by the end of the IGG campaign, we had modified the sensor to achieve a result as high as .92 and .94 R-squared values.
The problem is that our results were good but not consistent. Our design for manufacturing (DFM) was not where it needed to be in order to achieve repeatable and optimal results. We saw everything from low .8X all the way up to mid .9X R-squared values. We created a tool to help us align our laser and other optics, but this was a painstakingly long task and drastically increased the resources (including time) it took to produce one unit. We brought a design engineer on board to tackle our problem who has done DFM for Nokia’s smartphones (produced in the millions) among other smaller projects.
Great correlation to a proven research-grade sensor is very valuable, but knowing what size range of particles our sensors is actually seeing is a different conversation. It’s possible that we are detecting much larger particles above the 10 micron size range that just so happen to correlate to the amount of smaller particles, due to a favorable particle distribution curve. In order to determine this, we needed a more professional setup than the testing chamber we had made – particles tend to clump together so we needed to locate a proper wind tunnel and sophisticated method to aerosolize particles.
Very recently we found exactly what we were looking for, and we tested our sensors detection to monodisperse particles between the sizes of 1 to 10 microns. There was a risk here that our sensor would detect absolutely nothing, but instead we saw many particles across a wide distribution. We are now confident that we are seeing PM10 particles down to 1 micron in size. More testing is required to get more specific about our exact minimum detection threshold and maximum cut point. We will update you as we make progress and receive the results of 3rd party evaluations.
The RD02 TZOA Research Device that we are shipping out to Indiegogo backers will be greatly improved from the RD01 units described above. By beta-testing our original units, we received a lot of feedback, and it’s clear that there were some necessary improvements. We listened to you and made adjustments. The main improvements will be:
- Increased performance. The results from the characterization tests we performed (above) had a dual-purpose: we were testing a few different sensor configurations, and we identified a modification greatly improves our sensitivity to smaller particles, as a result we are seeing ~3X more particles. This modification will be in the RD02 units we deliver.
- Miniaturization. We are going from a dual printed circuit board design (PCB) to a single-board, multi-layer design. Having one board allows us to design a product that is significantly thinner. We are anticipating the RD02 units to be ~30% thinner than the RD01 units.
- Manufacturable design. Our RD01 units were hand assembled, aligned, and calibrated. The RD02 unit production will be a semi-automated process, meaning we can produce more units at a lower cost and with better repeatability / out of the box variability.
- Commercial grade. The units we are shipping out will have at a minimum full FCC/CE/IC certifications. We are also conducting RF and EMC testing.
- IO Port. We are adding a general purpose IO port for device interface. This means that upon request we can develop peripherals for the TZOA unit, whether that is a way to increase battery life (solar panel), internet connectivity(PLE or WiFi), expanded storage capacity, or other 3rd party sensors (air quality, GPS, etc…); we now have a port for those accessories!
- Maintainable. These units will include the ability to easily clean the sensor in case of contamination from extended use in extremely high pollution areas (industrial or developing countries).
- Improved software. Through Bluetooth Low Energy, our devices connects to the TZOA research app (currently private). We are making improvements to this that were asked for!
Unfortunately almost all of these improvements were discovered and scoped through an R&D phase that extended longer than we had planned for, and the implementation of these necessary improvements into the RD02 device wasn’t accounted for in our timeline. Instead of the original estimated delivery date of late-September, we are pushing back the estimated delivery date to late-October, specifically we are expecting to ship the pre-ordered units in the last week of October.
We have built extensive gantt charts and are confident that we can deliver these units at that time without further delay. This should not affect the progress of the “enviro-tracker” device’s estimated delivery date.
We apologize for any inconvenience. For anyone who needed units in September, please contact us and let us know if this will be a problem. We could potentially send you the lower-performance RD01 units. We hope to retain your business and work together to build a revolutionary new product.
info [at] mytzoa.com
San Francisco → Vancouver