X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-wi0-f172.google.com ([209.85.212.172] verified) by logan.com (CommuniGate Pro SMTP 6.0.1) with ESMTPS id 6094548 for flyrotary@lancaironline.net; Mon, 04 Mar 2013 11:36:26 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.212.172; envelope-from=rwstracy@gmail.com Received: by mail-wi0-f172.google.com with SMTP id ez12so2266285wid.17 for ; Mon, 04 Mar 2013 08:35:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:x-received:in-reply-to:references:date:message-id :subject:from:to:content-type; bh=+o5RxQvHEe8o3Ye472NH2QM/rlLtUpI+2mo1QOceRt0=; b=WPX6m2itHO42WogC8l0qgaX7gdg7n2K6vx2v8hPXj5cN2+Ts0vZNaGY+zHF8wf91yX 8lkUxPzOinHZEwxmtC9w+Uf65O7bJzAwR3No/n0gzOVlSKhGOoKEPztbB8LO7dKl/+yd RK7O1J0dm0MiPIpt5Ih75L1ZVI3FNZIlIJt9HTkOw/PDvL7vJ+xFctZpyGyNK+pW4sXN AUM/ULJpC8STpOv1u8MgO5hcfnHlcJTIo9CCzhr8ZdJfL12sD0zmn6rmbGje5RhVAS8b 3bycYNB7tW3SqeHMfP5AOSM7lCDCRRr8BW7W2Rd2uKmqm7r6wFpUPkb+bURl8Alnbwjs QC2Q== MIME-Version: 1.0 X-Received: by 10.180.85.97 with SMTP id g1mr13006952wiz.29.1362414947615; Mon, 04 Mar 2013 08:35:47 -0800 (PST) Received: by 10.194.154.164 with HTTP; Mon, 4 Mar 2013 08:35:47 -0800 (PST) In-Reply-To: References: Date: Mon, 4 Mar 2013 11:35:47 -0500 Message-ID: Subject: Re: [FlyRotary] Fly by wire From: Tracy To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=f46d0444036cfd481504d71bf252 --f46d0444036cfd481504d71bf252 Content-Type: text/plain; charset=ISO-8859-1 I'm still here Steve (waiting for the Suwannee river to flood), The FBW is installed and working (kind of) in the RV-8 but I decided not to make it a product after two very scary failures. One was on the ground which caused the engine to go to full throttle. That was caused by a heat shrink insulated wire connection shorting to ground where it was tie-wrapped to the fuel rail. Watch out for this cold flow failure if you use heat shrink insulated wire splices! Also, know what switches you need to turn off in a panic to kill the engine. The second failure was a software glitch in the primary controller which communicated with the EC3 on the serial bus in order to do things like Hold constant RPM, MP, Fuel Flow, etc. This one happened on final approach and the engine stopped responding to the throttle quadrant. I was only 300 ft AGL at the time and would not have made the runway (I know, bad landing habits) I regained control by switching to the backup (it has a redundant controller like the EC2/3). The backup did not have the serial communication links like the primary and it still worked. I eliminated the Hold functions and the serial connection to EC3 on primary FBW to eliminate the failure on it. Now all the FBW does is mirror the movement of the throttle quadrant at the RX-8 throttle body. These things could be fixed but the idea of trying to debug customer problems in the field with this much digital systems complexity made me decide that it was not a good idea. I'll share the schematic & software files if anyone wants to DIY one. You will need the development tools I use to use them though. Schematic & PC Board files are in DipTrace, software is in Microchip MPLAB and uses some PIC BASIC PRO compiler routines as well . MPLAB is free from Microchip BTW. Tracy On Mon, Mar 4, 2013 at 9:22 AM, Stephen Izett wrote: > Tracy, are you there? > > I seem to remember you set up your Rv8/20B originally with the Rx8 fly by > wire throttle. > Did you end up using it and developing a controller for it? > If so: > 1. Are you willing to share the hardware and code you used? > 2. Current consumption? > 3. Most importantly our thoughts on the value or otherwise of fbw? (true > single lever/pot! or perhaps just another failure mode) > > Cheers > > Steve Izett > Perth Western Australia > > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > --f46d0444036cfd481504d71bf252 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable I'm still here Steve (waiting for the Suwannee river to flood),

= =A0=A0 The FBW is installed and working (kind of) in the RV-8 but I decided= not to make it a product after two very scary failures.=A0 One was on the = ground which caused the engine to go to full throttle.=A0=A0 That was cause= d by a heat shrink insulated wire connection shorting to ground where it wa= s tie-wrapped to the fuel rail.=A0=A0 Watch out for this cold flow failure = if you use heat shrink insulated wire splices!=A0 Also, know what switches = you need to turn off in a panic to kill the engine.

The second failure was a software glitch in the primary controller whic= h communicated with the EC3 on the serial bus in order to do things like Ho= ld constant RPM, MP, Fuel Flow, etc.=A0 This one happened on final approach= and the engine stopped responding to the throttle quadrant.=A0 I was only = 300 ft AGL at the time and would not have made the runway (I know, bad land= ing habits)=A0 =A0 I regained control by switching to the backup (it has a = redundant controller like the EC2/3). =A0 The backup did not have the seria= l communication links like the primary and it still worked.=A0=A0 I elimina= ted the Hold functions and the serial connection to EC3 on primary FBW to e= liminate the failure on it.=A0 Now all the FBW does is mirror the movement = of the throttle quadrant at the RX-8 throttle body.

These things could be fixed but the idea of trying to debug customer pr= oblems in the field with this much digital systems complexity made me decid= e that it was not a good idea.

I'll share the schematic & so= ftware files if anyone wants to DIY one.=A0 You will need the development t= ools I use to use them though.

Schematic & PC Board files are in DipTrace,=A0 software is in Micro= chip MPLAB and uses some PIC BASIC PRO compiler routines as well .=A0 MPLAB= is free from Microchip BTW.

Tracy

On Mon, Mar 4, 2013 at 9:22 AM, Stephen Izett <steveizett@me.com><= /span> wrote:
Tracy, are you there?

I seem to remember you set up your Rv8/20B originally with the Rx8 fly by w= ire throttle.
Did you end up using it and developing a controller for it?
If so:
1. =A0Are you willing to share the hardware and code you used?
2. Current consumption?
3. Most importantly our thoughts on the value or otherwise of fbw? (true si= ngle lever/pot! or perhaps just another failure mode)

Cheers

Steve Izett
Perth Western Australia


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Homepage: =A0http:/= /www.flyrotary.com/
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