The one I like most is extruded polystyrene, you can find it in stores where you can buy laminate flooring, usually is packed in 5 - 10 sheets, 1 meter long .. And about the Velcro, I don't know how long will remain secured to the extruded polystyrene with only double sided tape, I sew it as this way, the velcro will be permanently mounted on the polystyrene
I made the sensors just to test which material is better because the temperature goes up and down in flight depending the flying patterns and speed, I really wanted to know the temperature between the battery and insulation ... today I made some tests but I think it was badluck, you see I used
double sided tape to secure the small battery on the blue plastic sheet, the badluck was I placed the battery exactly on the arduino reset button, and when I secured the sensors on the Inspire I think the elastic rubber band pressed the small battery on the reset button as it didn't recorded anything !!! And I just tested the device for 2 minutes just before I left outside, I checked the card and it logged both sensors, everything worked well except the moment when I attached the seonsors to the inspire.
I'll make some more tests when the weather will be better as it started to rain
About you project, will the coin battery be enough to power the arduino and the rgb led ? I really want to add an RGB led also, just to have a confirmation if the board is logging and saving to card, to prevent the events like the one in the morning when I was thinking everything is fine but in fact nothing was logged. The 250mah lipo battery I used is able to power the arduino + sd card + rtc through a boost dc to dc converter (3v to 5v) for 4 hours maximum (no sleep) , check the orange line in the graph, it's the battery voltage across 2 hours, and one hour the whole device and battery ware placed outside at 3°C, the 3 spikes on the red line are when I hold the sensor in my hand.
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