Date:         Wed, 13 Nov 2013 23:23:34 -0500
Reply-To:     James Eaton <jk_eaton@HOTMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         James Eaton <jk_eaton@HOTMAIL.COM>
Subject:      Re: Arduino and Vanagons
In-Reply-To:  <COL0-MC1-F141Y4HWPo00380bd7@COL0-MC1-F14.Col0.hotmail.com>
Content-Type: text/plain; charset="iso-8859-1"

Brett, the idle stabilizer that you're thinking of, the DIS (Digital Idle Stabilizer) from the CIS system, has no resemblance to the Idle Stabilization Valve (ISV) in a 2.1L Vanagon.  I had a Rabbit with DIS, and it stabilised the idle by advancing the ignition when the engine slowed.  The Vanagon system is an air control valve, driven by a PWM (pulse width modulation) system, that varies the duty cycle (proportion of time 'on' to time 'off' in the electronic cycle) to allow more air into the engine when the idle speed drops.  Inputs include an AC sensor, power steering pump sensor, ECU output, and more.  But you're right, the programming should not be too difficult, once the input values and output values needed are established.    Guess I better haul an oscilloscope home and check the output of the ISV controller!

I can haul an oscilloscope home because I teach electronics in a automation and Robotics program in a community college.  One of the courses I teach is the programming of microcontrollers, but not the hobby-level Arduino, rather its industrial competitor, the Microchip PIC microcontroller - similar idea, but many more 'industrial' applications.  Microchip PICs are inside most modern cars - there's supposed to be a European luxo-sedan whose 2013 model has more than 40 of them churning away inside, running everything from the anti-lock brakes to the climate system to the airbags.

As mentioned, it's not the ruggedness of the chip that matters so much as the ruggedness of the rest of the electronic assembly.  Potting the electronics after assembly helps, but component selection will be important too.

I, too, would be willing to help with this - but since I teach full-time and am pursuing a Master's, my time's a bit short.  Would have to pack development into holidays.

One last note - the original post talked about replacing the 'analog' ISV with digital version.  Tain't so, since the output of the ISV controller is a PWM signal (that's why your ISV vibrates when it's running!).  Replacing 1980s digital electronics with 2013 digital electronics is a good idea, though.

I love this group.  I have learned so much from you all, including the confidence to tackle projects on our much-loved Westy.

James
'91 Vanagon Westfalia Weekender (in Orly Blue)
Ottawa, ON

> Date:    Wed, 13 Nov 2013 07:30:35 -0800
> From:    Brett Ne <brettn777@GMAIL.COM>
> Subject: Re: Arduino and Vanagons
> 
> I have done quite a bit of programming with Arduinos over the past several
> years and would like to tackle this challenge.  I've got an 82 Riviera with
> an 89 VW Fox engine the has two Arduinos that monitor and display
> temperatures(inside, outside, fridge interior, fridge cold coils, fridge
> hot coils) and voltages (main & auxiliary).  Propane fridges become a whole
> lot nicer to use when you can tell exactly what's going on inside at all
> times.
> 
> My current hamster wheel is old school CIS, so it has no idle stabilizer.
> I would need someone knowledgeable to detail all the input and output
> voltages and behaviors.  I would especially need some input from someone
> who's used a scope on the primary side of their coil: what's the duty
> cycle? how high are the voltage spikes? are there any negative voltage
> spikes?  Microcontrollers do not like going above 5 volts, and a highly
> inductive device like an ignition coil is very  hazardous to them if the
> signal is not properly conditioned.
> 
> 
> Brett in Portland
> 
> "Albert", 82 Riviera
> 
> 
> Date:    Wed, 13 Nov 2013 12:06:37 -0600
> From:    Jarrett Anthony Kupcinski <kupcinski@GMAIL.COM>
> Subject: Re: Arduino and Vanagons
> 
> Arduinos are great fun, and in theory could probably do a great job of =
> replacing analogue components in older automobiles. Keep in mind, =
> however, that they are consumer-grade electronic devices, and depending =
> on the conditions that your particular automobile might undergo, they =
> may or may not be robust enough to last very long. YMMV. That being =
> said, they're cheap and easy to work with.
> 
> It sounds like Brett is interested to invest some effort in solving this =
> problem, but has mentioned that he may need the help of other in the =
> community.  For others who are interested, to work with Arduinos you'll =
> need to develop an understanding of two separate fields of study: =
> programming and electronic engineering. That may seem daunting, but keep =
> in mind that there is a huge and very supportive do-it-yourself =
> community surrounding Arduinos. It's not hard to learn the basics.
> 
> Simon Monk is a guru of all things Arduino, and you can't go wrong =
> starting with picking up one of his books and trying out the projects =
> outlined therein.  Someone also mentioned Make magazine, and you can go =
> to their website at makezine.com. Sparkfun.com is a vendor for things =
> Arduino related, and has a lot of information on their site, including =
> tutorials and videos.
> 
> -Jarrett
> From:    Brett Ne <brettn777@GMAIL.COM>
> Subject: Re: Arduino and Vanagons
> 
> Arduinos are great fun, and in theory could probably do a great job of
> > replacing analogue components in older automobiles. Keep in mind, however,
> > that they are consumer-grade electronic devices, and depending on the
> > conditions that your particular automobile might undergo, they may or may
> > not be robust enough to last very long. YMMV.
> >
> The programming is pretty trivial as long as long as you have a clear
> picture of what the input signals look like and how they should affect the
> output to the idle stabiliiztion valve.  As far as the electronics go, I
> belong to DorkbotPDX(motto: People Doing Strange Things with Electricity)
> and there are several people well versed in all things electronical that
> would be an excellent resource.
> 
> 
> 
> Brett
> Portland, OR
> "Albert" 82 Riviera
>