RiftFlyers G-Seat

[BrassEm]

G'day RiftFlyer,

Excellent work! Keep the update posts coming.

(I too have been inspired by Bergison's G-Seat and waiting for parts to come in to start mine. Wooden based as I don't have the luxury of welding.)

[telfel]

hi

can i ask did you make the flight controls or where they came from ?

regards Terry

[RiftFlyer]

Hi Terry,

The cyclic is from Komodo Simulations in the UK. The pedals and collective are from C-Tek in the US.

[fzxj520]

Try

[RiftFlyer]

Im back at this project again over the holidays. Sorry for the lack of updates but play time has been limited recently.

As a follow up to where I left off I want to ask about the picture posted by fzxj520 above. With the belt and pulley system I am using I have intentionally limited my mechanical movement while retaining full travel of the pots. The picture above suggests that this is incorrect!

I had thought its best to have full travel on the pots! Is my gearing causing the PID tuning issues In my earlier posted videos?

I'm interested to know some others views on this.

The alternative is using less pot travel for the flaps which I thought would cause a big loss of resolution (steps) or shortening my lever arm. I had hoped to get away with using the wiper motor arms without having to redrill them. My list of tools for this type of work is limited so the less drilling/cutting I need to do the better

[BrassEm]

I think what fzxj520 is pointing out that the BAD is introducing more rate of change than the GOOD. If the XPID as designed is expecting 1:1 but seeing 5:1 then unexpected instabilities are introduced by the change in rate of feedback for a given output. It is way more sensitive to a change in position hence more open to oscillations. The XPID response will need to be adjusted to compensate for the difference in rate of input to output.

I've adjusted my feedback rates by using op amps to electronically compress the pot rate of feedback. From a pot rotation of 280° to 90° for full scale voltage swing. 1:1 to 3.1:1. So I will be grappling with this issue soon too.

[spyderwash]

I solved using gear teeth 40 and 15

[RiftFlyer]

I solved using gear teeth 40 and 15

I will double check mine but I think that is similar to the gear ratio I am getting with my belt and pulleys.

[spyderwash]

I took many ideas from g-seat of bergson doing some editing

[RiftFlyer]

I took many ideas from g-seat of bergson doing some editing

Had you any problems with PID tuning in xpid? Like the jitter in my videos?

I have pure proportional control now (as seen in the last video) and hope it can work ok. I was unable to remove the hunting when using integral and derivative values in the PID.