THE DESIGN

1. 1Press GO on the control boxThe Pi in the box checks the battery and tells the micro:bit. The micro:bit radios GO to the MS-2000, so the turret starts its run.
2. 2It takes off and holds stillThe Pi talks to the drone over the drone’s own WiFi. A camera under the drone watches the floor and a laser range finder measures height, so it hovers without anyone steering.
3. 3It flies its patternSlow loops and bobs inside the net, about 3 feet from the turret, with the white window always facing the turret.
4. 4The laser tags the windowThe whole white face glows. A light sensor behind it feels the glow.
5. 5HIT goes back to the turretThe XIAO radio in the body tells the Pi, the Pi tells the micro:bit, and the micro:bit radios HIT on group 7. The turret cheers, and the box saves the hit.
6. 6It lands on its padAfter 30 seconds the drone comes down onto the cone cups and the box sends STOP.

1. 1Flies by itself during a runWhy: Nobody steers it. That is the whole point.Rev A: Python flight script on the Pi, position hold from the floor camera
2. 2Stays in a zone about 2 ft wide, 2 ft deep, and 1.5 ft tall, centered 3 ft from the turretWhy: That is where the laser and the camera line up, and it fits in the camera view.Rev A: Pattern 0.4 m across at 0.4 m high; lands if it drifts
3. 3Hit window at least 40 mm wide, hit pod lightWhy: The dot can land 13 mm off the camera aim between 2 and 4 ft.Rev A: 40 mm white window, 8 g body
4. 4Sends HIT on micro:bit radio group 7 within half a secondWhy: The MS-2000 turret already cheers on HIT, so the turret code does not change.Rev A: XIAO to Pi over WiFi, Pi to micro:bit over USB, micro:bit radio
5. 5Push button start and a launch padWhy: One press starts a run. The drone always starts in the same spot, facing the turret.Rev A: GO button on the control box; cone cups on the pad
6. 6Guards on all props, flies inside a netWhy: Spinning props and kids do not mix, and the net stops crashes and the beam.Rev A: Fence guard; pop-up bug habitat with the front open
7. 7At least 5 minutes of flying per chargeWhy: Five 30 second runs plus takeoffs and landings.Rev A: Three batteries, swap between runs
8. 8Slow enough for the turret to followWhy: The turret fires at most once a second.Rev A: Starts at 0.2 m/s; the first test sets the top speed
9. 9Added weight 25 g or lessWhy: That is what the drone can lift with 55 mm props, keeping about 40% extra push in reserve (our math).Rev A: Rev A estimate 26 g: the Can it fly? experiment decides

Rev A is about 1 g over. Our own math says the rating keeps about 40% extra push in reserve, so 1 g over still leaves plenty (see Can it fly?). The December experiment decides: if the drone climbs well and flies 5 minutes, it stays. If not, the fix is 65 mm props, which the LiteWing supports, and a bigger guard. That would be the first change order.