Yaw control not holding on handheld gimbal
  • I have an RCTimer gimbal with the alexmos board (the type with the 3 axis on the main board plus the 3rd axis board mounted on top of the main board.
    I have a Canon 5D, it's well balanced on the gimbal however when I tilt the whole rig to the left or right past about 30 degrees then the yaw 'releases' and falls, it will not hold, it seems there is not enough torque being developed by the 5208 200T motor.
    I have tried many PID settings and can get a steady and stable response on all axis but it just doesn't 'hold' the yaw when the whole rig is tilted.
  • The more power to the yaw, the better hold. My gimbal will do this too. The motor just can't hold the entire 8lbs of everything below it. But unless you really need it, it should be OK. Try turning up the power all the way and see what happens. I had my 3S Lipos at 240 on Yaw and it was still OK. Of course you'll have to turn down P to around 15-25, I to .1-.3 and D as high as you can. 35-40.
  • Thanks. I have had comments from other forums where people have said that the yaw will hold, but i'm not sure about this, as you say there is a lot of weight with a 5D hanging, so when you tilt the whole rig over the arm/levarage (moment) creates a large load on the motor, I will work out the actual load if I can remember my formulas of arm x moment etc etc! Theoretically we should be able to calculate exactly what load the motors can take and how much current is required for it to maintain position.
  • I have spotted an error in my build, the tube from the yaw motor was not correctly positioned and was out of balance, I will make adjustments and I think it should solve the problem..
  • Dear zeb, indeed i strugled a while in the beginning with this thinking theres not enough torque,
    The solution is very simple, loosen the yaw motor and slide it forward or backward, small time each time, tighten it again and try again. If you move to the right and your camera is falling aslo to the right this means your yaw bar has to slide a little bit back. There should be a balance between your camera and your backside. If your camera is to far put to the front its logical it will fall over.
    I solved this by putting my electronicsboard at the back of the roll motor and then but my 4s 1600 mah battery also at the back of this box. Now i have already a good balance between the camera and the back part. When finished your can lean completely lean from right to left wich gives you the magic look :) .... Even with a monster motor on the yaw setting it to maximum powers will not hold the complete setup if the yaw bar is not balanced also.
  • Yaw is easiest to balance just rotating outer axis roll 90 degrees without power on.
  • Thanks Vandepoel, yaw now balanced. Which also relieves my worry about the current draw of the motor through my slip ring wires which are very thin, this will free up wires for joystick use (still can't get the correct drawing for this, all information is for the older/different type boards than mine).

    Still working on the pitch and roll as the 24-70 lens is very heavy, I think I will need to drop the camera lower, I have ordered longer pitch arms to give more flexibility balancing larger cameras so hopefully that will sort it out.
  • yep, i redisigned mine to to get the pitch arm lower for heavyer setup. when go with such a heavy lens make sure your D faktor of the pitch is high enough. go much to high like D 40 until its buzzing and then lower the value until its good .... use a monstermotor like 8017 for the roll, will give you some headroom also and better results

    good luck
  • Thanks.
    It is almost perfect now, I just need to speed up the recovery response slightly and it will be all good. Now to get the follow mode and joystick hooked up. Not sure how to connect the joystick but will research. I have the board with the 3 axis connectors on the main board plus the 3rd axis mounted on top.
  • Hey Zeb, Any updates on getting the joystick soldered in? And any tips on the follow mode, lessons learned? Thanks