Infinity Grip Electrical Project - need advice and info

Hi all,

I am in the process of planning a stick change in my RV-8 (pilot's seat) from a Ray Allen G205 grip to an Infinity Grip (hereafter referred to as IG)


Right now the stick functions are:

PTT
Flaps up and down (2 buttons)
Auto-pilot disengage.

The elevator trim is a ON-OFF-ON rocker switch on the instrument panel. I'd like to move that to the coolie hat of the Infinity.

I have a few questions regarding this project and I've worked out a basic plan about which I would appreciate comments/criticism/suggestions.

Instead of writing about everything in one massive post I'd like to present a question or issue one at a time.


Issue #1: Relays
=================

The Ray Allen web page says this:

"The modern design G101B, G205 and G207 stick grips use four, flush fitting pushbutton switches to control one or two axis electric trim. These SPDT, momentary contact switches are rated at 5 amps. They can be wired directly to Ray Allen trim servos, eliminating the need to wire relays in your trim system when one grip is used."

The IG web page sells a relay deck so my assumption is that for the flaps and elevator trim servo I need a couple of relays (each) on the relay deck.


Question #1:
============

Do I need a relay for the PTT? What is the current like on a PTT
switch?

Or can that be just a direct connection to the PTT switch on the IG?

Thanks!

You don't need a relay for PTT.
For trim and flaps, you do need relays or a controller such as Rich Meske's FPS or a Safety Trim controller.

Here's a trim and flaps example (using my own auto-trim controller) http://www.vx-aviation.com/sprocket/photos/panel_elec/schematics/TRIM.pdf

And here is how I wired my IG: http://www.vx-aviation.com/sprocket/photos/panel_elec/schematics/GRIP.pdf

And since you are a software expert, check this out: http://www.vansairforce.com/community/showthread.php?t=151119&highlight=Arduino

To add to the list of options, a regular air contributor here Pat Hatch offers a relay board along with a well thought out wiring diagram designed specifically to interface with the infinity stick grips. I've installed his board. As a new builder, I had many basic questions and his support was exceptional.

http://www.phaviation.com is the link to his site.

Gregg,

You might have a look at one of our relay boards that is well suited for the Infinity grip. It's a dead simple relay board with 3 channels for pitch and roll trim, and flaps actuation. If you check my web page you'll see more information on wiring for the Infinity.



What's a little different with this relay board is that it uses D-sub connectors with the machined pins instead of the screw terminals for connecting your wires. I'll be glad to answer any questions you might have.

No trim relays with Dynon SV-AP-Panel

Do you have an autopilot?

FYI Dynon's SV-AP-Panel uses normally open pushbuttons to control trim and will accommodate two sticks.

Perhaps other APs do the same.

From the Dynon install manual:

"In addition to the AP mode buttons, the SV-AP-PANEL includes an adjustable, speed-sensitive trim controller, eliminating the need for relay packs or a separate trim controller... pushbuttons (typically, on the stick)... up to two trim motors - such as those made by Ray Allen.

A set of pushbuttons can optionally be installed for the copilot.

The pilot?s pushbuttons take priority over the copilot?s pushbuttons. Pushbuttons used for Trim Motor Control must be Push Button Normally Open (PBNO).

Pilot trim controls override Copilot trim controls.

If a trim control button is detected as pushed when power is first applied... trim control will not activate until the button is first released.

If a trim control button is pushed for more than five seconds... trim control on that axis will be temporarily inactivated until the button is first released."

johnbright said:

Do you have an autopilot?

FYI Dynon's SV-AP-Panel uses normally open pushbuttons to control trim and will accommodate two sticks.

Perhaps other APs do the same.

From the Dynon install manual:

"In addition to the AP mode buttons, the SV-AP-PANEL includes an adjustable, speed-sensitive trim controller, eliminating the need for relay packs or a separate trim controller... pushbuttons (typically, on the stick)... up to two trim motors - such as those made by Ray Allen.

A set of pushbuttons can optionally be installed for the copilot.

The pilot?s pushbuttons take priority over the copilot?s pushbuttons. Pushbuttons used for Trim Motor Control must be Push Button Normally Open (PBNO).

Pilot trim controls override Copilot trim controls.

If a trim control button is detected as pushed when power is first applied... trim control will not activate until the button is first released.

If a trim control button is pushed for more than five seconds... trim control on that axis will be temporarily inactivated until the button is first released."

Click to expand...

Thanks but the autopilot controls are part of the TruTrak EFIS and is not part of this project.

Ok thanks for the verification that the PTT does not need a relay.
I didn't think it did but, no harm in asking to be certain.

Thanks for the recommendation of the Pat Hatch relay board. Alas I already bought one.

However the next step in the planning is wiring and mounting.

I have the Composite Design Trim relay deck. One design requirement I have is that the stick MUST be detachable from the wiring in a convenient fashion. Right now the wires lead from the buttons on the stick all the way to the devices with no connector. I would like to remedy that.

My first thoughts, given the Composite Design board and the fact that the terminals on the board are screw terminals would be to:

1) Wire a D-sub to the stick wires.

2) Mount the relay board in a plastic box

3) Run wires from the relay board inputs (ring terminals) to a D-sub on one end of the box. The stick D-sub would connect here.

4) Run wires from the outputs of the relay deck to a D-sub on the other end of the box.

The device wires D-sub would connect here.

5) Run a pass through wire that connects an input D-sub pin to an output D-sub pin for the PTT.

This would require 4 D-subs that I would have to wire up.

Were I to get the PH board, it already comes with an input and output D-sub. So I would have to wire up only 2 - one at the stick wire bundle end and one for the devices.

So it's worth considering the PA relay deck. I see it uses the same relays as my Composite Design.

And then next I need to figure out where to mount the box.

Before I knew of the PH relay, I purchased the Composite Designer 3 way relay board. I bonded it to the floor of my -7A with plastic spacers at each corner.

The Infinity wires go into a 15 pin DSub for easy disconnect/removal of the grip should it every need replacing. The same DSub on the co-pilo stick allows easy removal.

I concur!

jump4way said:

To add to the list of options, a regular air contributor here Pat Hatch offers a relay board along with a well thought out wiring diagram designed specifically to interface with the infinity stick grips. I've installed his board. As a new builder, I had many basic questions and his support was exceptional.

http://www.phaviation.com is the link to his site.

Click to expand...

I used Pat Hatch's "Ultimate TRB" servo board this time last year when I converted my manual trim system to electric trim for both elevator and aileron trim functions and installed Tosten Military Style grips in my RV7A. My Tosten grips had the "coolie hat" trim button which does require a trim controller to prevent adverse trim actions. My grips also included buttons for electric flaps, PTT, autopilot engage/disengage, transponder ident, comm and freq swap - depending on whether it's the pilot's or copilot' grip. Pat's Ultimate TRB handled this conversion completely.

I will also tell you Pat's assistance was totally fantastic! He made a very difficult project very doable - and this is a guy speaking who can barely connect two wires together. He's a first class guy and his product is reasonably priced but more importantly is supported by his personal assistance.

Ray & Jim, thanks for the kind words! Truth is I really enjoy playing with this stuff and love helping others get it right.

Here's an example of two Infinity grips wired directly to my Ultimate relay board:



This is our bench tester and demo rig. It has an actual flap motor loaded with a spring to simulate an aerodynamic load on the flaps. By loading the flap motor I can get the amperage up over 5 amps for test purposes. All the lights verify the other grip functions like PTT, Ident, A/P disconnect, etc. Trim motors are simulated with RC servos.