I’ve used Arducopter with some Mini-APM’s on some projects. My newest project will use “Throw Mode”. It will be a Rocket Boosted Quad, that after arming, and taking off 100% on rocket power, when it reaches apogee, I expect (!) for Throw Mode to stabilize the model into a hover.
So, can someone confirm to me that Throw Mode should work for this? It’s going to be accelerated by rocket thrust for about 1.5 seconds, then coast for a bit to apogee.
What does Throw Mode use for sensing apogee? Barometer only, or is it using inertial measurements, or a mix of both? If the Quad begins to veer to the horizontal under rocket thrust, I’m wondering if Throw Mode would detect apogee due to the barometer, or if not, whether the IMU might not detect apogee due to continued acceleration but by the horizontal axis. So this is a secondary issue, whether Throw Mode could likely kick in save a bad launch that is still thrusting but having reached apogee and losing altitude.
The rocket quad should be aerodynamically stable, but if one of the windmilling props spins differently there may be uneven drag to pull it to one side. Due to the design, it’s not practical to fold for boost and locking the blades to not spin on boost seems more of a risk of something to go wrong.
If there is a better place to ask, please let me know. I am asking in Copter 3.5 since I’m not sure how stable 3.6 is. I’ll be using a Pixracer for this, since the Mini-APM’s can’t run any version that has Throw Mode.
I know, the above may come off as an outlandish idea. But I have been flying model rockets since 1970, R/C planes since the late 70’s, and my last Quadcopter was this one (conventional in flight, not in looks or fabrication): https://www.rocketryforum.com/threads/flying-r-c-lunar-module-quadcopter-project.137174/
I will say that I am not planning to do a rocket boosted Lunar Module. But the design I do want to do this with will be a bit similar, but aerodynamically stable.