I've got one of the new hexacopter kits from JDrones (nice kit Jani, BTW). I've got the copter assembled and I'm running some of the pre-flight tests, but I've run into some problems. Specifically, movement of the pitch stick results in the wrong motor response. If I push forward on the stick, the front motor spins faster. If I push backward on the stick, the back motor spins faster. I've verified the behavior using the "motors" command in the terminal of APM - forward stick makes the back motor spin up, back stick makes the front motor spin up. Roll seems to work exactly as it should (move right, right two motors spin up). Here's what I've checked for possible causes:
APM Planner verifies that when I push forward on stick, it is receiving a signal for forward on stick (pulse increases), so signal is not 'reversed'
I've double and triple checked that PDB is wired correctly (or at least as specified in the manual). Front motor is fed by output 1, rear motor is controlled by output 2 from
APM is facing the right direction - RC pins face motor controlled by channel 2.
Any thoughts as to what is causing the problem?
An obvious solution would be to just 'reverse' stick direction in either my TX or APM Planner setup, but I'm not sure what problems such a work-around may generate down the road.
Thanks in advance for any advice
Todd
Replies
depending on your tx it's possible you were using heli mode. I've never made the mistake of putting it in heli mode so I don't know how it responds but remember that quadcopters should be controlled like planes as far as the tx is concerned.
Follow-up:
The hand tilt test indicates that the copter acts the way it should, pitching it forward by hand causes the front propellers to spin faster, pitching it back causes the back propellers to spin faster.
So I simply reversed the signal from the TX. Movement of the sticks now causes the copter to respond the way it should, and the copter still passes the hand pitch/roll/yaw test. So hopefully the issue is solved (recording here for posterity and future troubleshooters).
However, I'm still interested in know if anyone has any insights into why the problem happened, or thoughts on potential problems my work-around may cause in the future.