Yesterday I had a few tests with our Tiger Shark in Octa Quad configuration.
The tests were made to see how the copter would cope the loss of one or two propellers.
Obviously the test was in a ideal condition where the propeller just loosens and falls off the Octo.
The test was done by removing first 1 propeller, then two propellers spinning in opposite and same direction.
Without 1 propeller the copter flew as it had all the propellers. There was no feeling of something wrong. It took off and landed easily.
Taking off two propellers spinning in the same direction (lower front left and lower back right) resulted in a copter that in take-off yawed a little. Once the I term build up, it was perfectly straight. It was a little unstable due to the fact that two arms were "stronger" than the others, but generally it was perfectly stable even with some wind.
Taking off two propellers spinning in same direction (lower front left and right) resulted in a copter trying to move forward with quite a pace. I took a little pitch back to keep it still, but the overall stability was amazing.....
X8 will not take the loss of two propellers on the same arm, that would result in a crash, unless the recent algorithm gets published and then implemented in ACM code. :)
The code is based on APM:Copter 3.1.2 but runs on VRBRAIN.
Propellers are 13x5 T-motors on the upper and Graupner 13x8 on the lower.
Motors are 3508-700KV with 10Ah 4S battery.
Total weight was about 3.0 Kg.
Thanks to VirtualRobotix.it for the frame and the electronics, and thanks to the APM:Copter dev team that allowed us to fork and use their code, that is progressing fastest than speed light!