A 12 second loop. A drone takes off from a landing pad, flies out to a work area and works back and forth while a large battery bar below drains from full. The bar has three planned marks: a red low-battery warning zone at the bottom, an orange reserve above it, and a blue return mark above the reserve that allows for the trip home. When the charge reaches the return mark, the drone stops work and flies home, landing with the reserve still intact and well above the warning zone. With wind and cold selected, the reserve and the return allowance are both larger and the battery drains faster, so the drone returns much earlier and does less work. All levels are schematic. The still frame shows the calm case just after landing with the reserve intact.
