Servo going from 0 to 180 w/out stopping

[ObiOne-Kenobi]

Hello,

My servo is traveling the 0-180 range without stopping in between. :eek:

I'm using a USB servo controller card and have connected the HS-322 servo to the SimKit VSI gauge. When the VSI needle in FS2004 crosses above the zero line, my servo goes to the upper end. And when the needle in FS re-crosses the zero line (to the down side), the servo comes from its end position and goes to the opposite end position without a hint of stopping in between.

Any ideas on how to solve this?

Cheers,
Obi-One

[alandyer]

Doesn't simkits have their own driver ?

I need futher information from you ?
What offset are you working with ?
How have you calibrated ?
Have you examined values FS is sending ?
What are they ?

[ObiOne-Kenobi]

Alan,

No, SimKit doesn't come with any driver; one will need to purchase their CCU (Central Control Unit). I thought the Phidget servo being driven by its controller would be an easier and cheaper alternative, but I might be wrong of course.

My plan is to go through the process life cycle with one unit (putting the gauge together, interface with the phidgets, FSUIPC and FS, and test fligh it), getting the necessary experience/knowledge and then invest in more instruments, to eventually build a complete c172/182 cockpit.

Back to your questions. I'm using the following values for the Vertical Speed:
Offsets: 0842 - Length: 2

FS Values:
Yes, I can see the FS Values in the corresponding column and they range (roughly) from -2000 to + 2000.

For the calibration, I left the default 'Max Servo Travel' to 180. Servo Zone is using the default Min of 0 and Max 180.
FS Value in calibration is showing 0 and Servo Position is showing Max.

I had to select the 'Invert' field; the servo and FS were opposite.

Thank you for your patience, understanding and support.

Cheers,
Obi-One

[JBaymore]

Obi One,

I am watching your success with this....... if you get this figured out... I may be headed for a couple of simkit guages myself. I have always found that the gauges look gteat...... but the cost of the main "interface" to run them made them impractical for using only a couple of them.

If the Phidgets thing works.... then the kits make sense.

Thanks for being the "gueina pig" on this :)

best,

..................john

[ObiOne-Kenobi]

JBaymore,

Once I manage to have it work, I will post my findings here.

Although I am convinced that this is a cost effective solution, I'm wondering about the practicality of the solution for, say, 14 gauges; it will require about 21 servos (for a c172/182 project).
I haven't figured out yet, what the most efficient solution will be, to control and manage 21+ servos.

This is something to think about. Will keep you posted.

Cheers,
Obi-One

[JBaymore]

Obi One,

In my simpit I will only need a few "steam guages" as "backups" to the glass cockpit stuff...... so it might be more practical for me than you. Good luck with solving it.

best,

......john

[Steve Daly]

Based on what I can see from the simkits website...

The simkits use servo output gearing to drive the needles. This means that they are probably designed to use standard 90° servo output. If this is true then the needle is probably being overdriven by a servo that is trying to do 180°.

Try setting the servo travel for 90° and see if it behaves better.