Technology for Science and Education
“The Homers” is now reporting. Before conducting signal tests, the main board and the ADC board were replaced. The Xbee and CPU were retained. This was done to eliminate soldering/construction problems. However, that seems to have been the problem. The unit is now reporting and data is available under public reports.
Because of low numbers on reporting unit “Super Stars”, I readjusted the dendrometer and cleared the data.
Unit “The Homers” is not reporting. This is most likely due to poor signal strength. I will use this as an opportunity to develop mesh networking capabilities.
Other units required no changes.
Unit ran from 14 July to 21 July, almost a full 7 days. I replaced the battery today and performed basic inspection. It required no other changes.
Remember you can find public reports here.
The Make: Nature workshop at this summer’s Black Rock Forest Summer Science Camp was a success! Twelve awesome kids got a chance to learn to how to solder and the basics of circuitry. They used those skills to construct and deploy their electronic, wireless point dendrometers on four red maples near the science center. Looking at the data collected with their devices, the kids got to compare their hypothesis of tree stem shrinkage and swelling from water use against actual dendrometer data. Be sure to head over to the data collection site to check out the charts!
There seems to be a bit of variability on battery longevity. The last charge at the Lamont installation lasted over 6 days. This would indicate a variation in current usage by the reporting unit, perhaps related to heat.
Next week we will be assembling and deploying four new dendrometers at the Black Rock Forest Consortium Summer Science Camp. A number of middle schoolers will be able to see what goes into constructing and installing the dendrometers and get a chance to answer some questions about how our trees change from day to day.
It seems that wet foliage and understory can contribute to signal loss when the signal is weak to begin with. At the research and development network at the Lamont Doherty site we experienced signal loss after rain. After repositioning the logging unit in a window we experienced much improved results. We also changed radio frequency settings to avoid interference from nearby wifi.
Battery life is at 5 days using a 4,000 mAh battery. In development is expanding the reporting period to improve battery life.