Alex, Did some changes on 1.7 tri for Bi-copter. Its almost okey w/the directions of the servos.
#ifdef BI
motor[0] =rcCommand[THROTTLE] + (axisPID[ROLL] * 1/8); //RIGHT
motor[1] =rcCommand[THROTTLE] - (axisPID[ROLL] * 1/8); //LEFT
servo[0] = constrain(1500 + YAW_DIRECTION * axisPID[YAW] - axisPID[PITCH], 1020, 2000); //RH TILT SERVO
servo[1] = constrain(1500 + YAW_DIRECTION * axisPID[YAW] + axisPID[PITCH], 1020, 2000); //LH TILT SERVO
But the problem is the picth yaw direction.
When the front nose goes downward both servos goes upward. Its should be the other way.
same when nose goes upward both servos goes dowward. Thats why the level picth its not holding.
Thanks,
Tony