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paramotor/paraglider helmet mount - issues with lateral force and maintaining a straight roll axis.
  • Guys, I have been using and buying your boards and gimbals based on them since they came out. I love em to bits.

    But I need your suggestions for this:

    - I fly paramotors. I have an old alexmos board I hacked together with old 2.2 odd firmware - 2 seperate boards - one doing yaw, one doing roll/pitch that I've been using since the early days - and it works a treat - but it's getting long in the tooth and it worn out.

    I have bough a new 32 bit based gimbal with encoders from CAME-TV and am trying to get this working for helmet mount.

    My issue in a nutshell is that when flying there are times where there is a lateral force (i.e. during turns).

    it can be >1g but is usually much lower - turns are quite slow, and swing you out through a turn.

    hence it's important to trust the gyro more than you might for a quadcopter.

    However, trying pushing the gyro trust up to 150 or so and we get the horizon drift issue over time - so footage ruined.

    Trying it lower, and during any turns its trusting accelerometer data, and hence the horizon is immediately very very rotated.

    I'm trying everything here, but there may be some very simple things you can suggest yourselves - hence asking ?

    for an aircraft, with helmet mounting - max speed 25 mph, max angle of turn where I'd expect to keep a horizon (i.e. does on old one) is maybe 90 degrees per 5-10 seconds.
  • you need more power !
  • Yes, the horizon will drift under lateral accelerations


    Good IMU calibration (temperature as outside the temperature is often different) will help with suitable gyro thus, but not solve the problem. I think on the above kind of video it is actually natural. Also it is not too difficult to corret on editing phase.

    There is solutions, but they are not simple.
  • It's not the issue during a turn. Basically there is a general roll over time side to side even when flying straight. It is so noticeable because the horizon is of course a straight line right across the frame. Any deviation is very obvious. So to correct in post every single shot would need correction separately a different amount.

    As I say, the old 2 board setup does not have the same issue:

    https://youtu.be/9n44SO2a2v8

    I've not flown with the new one yet but that is the standard I'm aiming for basically.

    It seems a tricky trade off between keeping the gyro trust high enough to ignore lateral acceleration but not start drifting.

    Ideally I don't care about straight horizon when I'm turning. But when I'm going straight I want it rock solid level and not rolling at all. As its here that even 2-3 degrees is noticeable and if its a constantly varying drift -3 to +3 say its impossible to edit out