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Transition to landing from any state
Automated with pilot override
Initiate constant speed gaussian profile for descent
If accurate GPS or Ground height sensor:
Gaussian profile/deceleration on approach to ground
velocity
Landing Detection
Emergency state (Can be automatically transitioned to on coms loss)
Considerations:
Spin up to takeoff speed (Reduce current spikes/easier on ESC & motors)
Automated, but can be pilot overridden
Transition to hover at set height (4m) if no pilot input
If comms loss during takeoff transition to hover in place and if timeout passes transition to landing?
Uneven takeoff surfaceUneven landing surface
Eg, Only half drone experiencing ground effect, try not to crash
Spin-down after landing is detected
The Plan:
MVP first:
At signal (Not when powered on) can descend using a state in path manager that passes targets to attitude manager
At another signal transitions out of landing state
When altitude has been constant for a few seconds and below threshold then transition out of landing.
Later steps:
Ensure drone is in a hover before descending
After descent, transitions to a standby or disarmed state
Update the target ground height with a sensor (Would be nice to stop assuming earth is flat)
Use Passby control to “spin down” motors to 20% throttle after landing (in standby state), increases motor longevity and can prevent motor cogging.
Use optical Flow sensor to keep waypoint targets perfectly vertical
Add a better landing detection system (possibly with optical flow sensor)
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https://www.desmos.com/calculator/tjtx8ogtno
Code Prototype:
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| breakoutMode | wide |
|---|---|
| language | cpp |
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Waypoint-based Landing Takeoff Manager (Not for 2023 Competition):
Not in use as velocity target provide smoother flight.
Use waypoints as targets that the drone attempts to meet at a set frequency. As drone approaches target, shorten the distance to the next waypoint to slow down drone ascent.
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