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Wideband Sensor with Controller, Spartan Lambda Sensor, $105 
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Wideband Wizard

Joined: Tue Jun 10, 2008 2:53 am
Posts: 184
Location: Toronto Canada
Post Wideband Sensor with Controller, Spartan Lambda Sensor, $105
I hope Fred will tolerate my loitering and solicitation.

I just released Spartan Lambda Sensor, http://www.14point7.com, my website is under construction so please forgive any typos and the unfinished look. It is a Wideband O2 Sensor with built in controller, $105 for a single unit, $400 for 4 units, and $600 for 6 units.

I primarily designed this product to bring individual cylinder metering affordable to most tuners and racers.

It has a 0-5[v] linear output; 0.68[Lambda] to 1.36[Lambda], and a simulated narrowband output.

The unit is built with a 32 bit ARM Cortex uC, everything is digital, analog components was not a luxury available due to space limitations.

The pump cell of the sensor is driven @ discrete TTL logic levels; 0[v] and 5[v] no other voltages in between, I call my method "Binary Drive" and I am in the process of applying for a patent for the design. Being able to digital drive the pump cell is something that no other controller is capable of even the ones with "Digital" stamped all over their product literature.

The result is a very fast controller, depending on the exact metric and test methodology my unit would either be the fastest or a close 2nd fastest.

My design does not require free air calibration, I calibrate each unit with calibration gas before it ships.

My Design measures the sensor temperature through the nermest cell impedance like all controllers should, it does not use the pump cell impedance as a proxy like another "Digital" controller does. The result is very tight temperature control, as all respectable controllers should be able to do.

If you guys are interested in doing a group buy, I can offer a good deal. I am not looking for beta testers, the product has already been well tested and validated.

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Last edited by toalan on Fri Sep 07, 2012 9:52 pm, edited 1 time in total.



Fri Sep 07, 2012 2:26 am
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Post Re: Wideband sensor with controller for $105
toalan wrote:
I hope Fred will tolerate my loitering and solicitation.

Of course, however I think you should do a few things:

A) put the product name in the title
B) give yourself a signature and maybe avatar
C) include this picture of the thing in your post:

http://www.14point7.com/Spartan.jpg

Image

Quote:
my website is under construction so please forgive any typos and the unfinished look.

I think it looks good! Only thing is that with everything else so bold the price list under each one is hard to spot.

Quote:
I call my method "Binary Drive" and I am in the process of applying for a patent for the design. Being able to digital drive the pump cell is something that no other controller is capable of even the ones with "Digital" stamped all over their product literature.

Very cool! Best of luck with your application! :-)

Quote:
The result is a very fast controller, depending on the exact metric and test methodology my unit would either be the fastest or a close 2nd fastest.

Congratulations on the achievement! It's been really cool watching your stuff evolve over the years! :-)

Quote:
My design does not require free air calibration, I calibrate each unit with calibration gas before it ships.

How does that relate to sensor aging in the long term?

Quote:
like another "Digital" controller does.

OK, who do you mean by "even the ones with "Digital" stamped all over" and the above, could it start with an 'I'?

Is there any sort of digital output on it such as rs232 or can or similar? Given the size, I'm guessing not.

I love it! Perfect not just for individual cylinders, but also for bikes and other compact applications!

Fred.

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Fri Sep 07, 2012 8:47 am
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Wideband Wizard

Joined: Tue Jun 10, 2008 2:53 am
Posts: 184
Location: Toronto Canada
Post Re: Wideband Sensor with Controller, Spartan Lambda Sensor,
Thanks for the tip about the posts and user profile.

The current website, is just a place holder until the new site with dedicated product pages is up.

Serial comms may be available in the next version, if it does show up it will only be TTL logic levels because there is no room for a proper level shifter.

Regarding Free Air Calibration:

The Wideband sensors lose very little accuracy due to age. The primary way a sensor ages is build up of carbon in the chamber walls that hold samples the exhaust gas, this build up slows the rate of diffusion the same amount for both rich and lean gas, because of this effect both rich and lean gas to the same effect it will have no impact on accuracy. The big impact comes in the form of slower response times as now the diffusion rate is negatively effected due to carbon build up, there is no way to account for the loss of response time with or without free air calibration.

The primary way to extend sensor life and reduce the effects of aging is to precisely control the sensor temperature so that most of the carbon build up is burned off, towards that goal my design uses the nermest cell resistance for temperature measurement (all controllers on the market except one brand use the nermest cell resistance because it is what the sensor datasheet specifies), the other Digital brand uses the pump cell resistance as a proxy for nermest cell resistance which is not as accurate. Their way is nermest cell resistance = x*pump cell resistance, the x is calculated periodically through calibration. This is the reason why the other Digital brand requires calibration so often is they need to calculate a calibration factor for free air operation of the pump cell (for accuracy) and also need to calculate the coefficient between nermest cell resistance and pump cell resistance.

Free Air calibration does net you minor increases in accuracy, I do put in that feature on all my widebands with a method to display the free air calibration value, for products with no easy way to show the free air calibration value I do not put in the free air calibration feature as there is no way to differentiate between real problems with the controller and sensor vs a bad free air calibration.

If I do end up putting in serial comms on the unit in future versions of Spartan Lambda Sensor, then I will put in the free air calibration feature which will be triggered through the serial comms.

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Fri Sep 07, 2012 10:29 pm
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QFP80 - Contributor

Joined: Sun Jan 27, 2008 10:25 pm
Posts: 68
Post Re: Wideband Sensor with Controller, Spartan Lambda Sensor,
What kind of sensor are you using for these? I notice that you don't specify what sensor any of the products on your website are compatible with. It might be a worthy addition?


Wed May 08, 2013 4:04 am
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TO220 - Visibile

Joined: Mon Sep 03, 2012 8:48 pm
Posts: 8
Post Re: Wideband Sensor with Controller, Spartan Lambda Sensor,
LSU 4.9

Fastest and smallest thing you ever seen. Forgot the big brands. This thing was different.

When it was arrived my partner unpack and phone me to complain to Alan was forgot the ship controller board. However after some 2 hours he managed to find circuit...

Dear Alan.

Is your next version ready ?. That serial connection may solve our connection problem and make us very happy. We want to use your products in our products.

Winter is coming, and we deeply need more controllers than ever.

Our best regards...


Sun Aug 18, 2013 7:59 pm
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Wideband Wizard

Joined: Tue Jun 10, 2008 2:53 am
Posts: 184
Location: Toronto Canada
Post Re: Wideband Sensor with Controller, Spartan Lambda Sensor,
The next version is one with a connector instead of being soldered directly to the sensor, this will be available in about a months time.

The next version after that will have CAN bus and serial, use all automotive qualified parts, plus some new wideband control stuff I have been experimenting with lately. No idea when this will be available as I have to learn a new microcontroller platform to do it properly.

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Sun Aug 18, 2013 9:39 pm
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QFP80 - Contributor

Joined: Tue Feb 12, 2013 5:43 am
Posts: 30
Location: Scarborough, ON
Post Re: Wideband Sensor with Controller, Spartan Lambda Sensor,
You do realise, you're obsoleting your own SLC-OEM? :lol2:

I was seriously pondering marketing a dual SLC carrier with MS-CAN in a rugged enclosure, but I can't compete with the guy making the things. Where the heck do you get your sensors, that you can sell the complete units that cheaply?!

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Mon Aug 19, 2013 2:36 am
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Wideband Wizard

Joined: Tue Jun 10, 2008 2:53 am
Posts: 184
Location: Toronto Canada
Post Re: Wideband Sensor with Controller, Spartan Lambda Sensor,
DonTZ125 wrote:
You do realise, you're obsoleting your own SLC-OEM? :lol2:

I was seriously pondering marketing a dual SLC carrier with MS-CAN in a rugged enclosure, but I can't compete with the guy making the things. Where the heck do you get your sensors, that you can sell the complete units that cheaply?!


Yes, to my great dismay I knew the spartan design would cannibalize SLC-OEM. My open source lambda controller, SLC Free, would also cannibalize into my spartan sales as well as other lambda products. But I am a firm believer in progress, and not to sit around milking all that I can out of the work I have already done in the past.

The truth is that sensors cost me $47 each, so I am not getting a great deal on them because my volume is low.

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Tue Aug 20, 2013 7:43 pm
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TO220 - Visibile

Joined: Mon Sep 03, 2012 8:48 pm
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Post Re: Wideband Sensor with Controller, Spartan Lambda Sensor,
Just asking,

What if you made new version as a Arduino shield ?


Sat Aug 31, 2013 6:06 am
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DIP8 - Involved

Joined: Fri Aug 13, 2010 6:07 am
Posts: 27
Post Re: Wideband Sensor with Controller, Spartan Lambda Sensor,
Delifisek wrote:
Just asking,

What if you made new version as a Arduino shield ?


What's the point ??? :indiff:


Sun Sep 01, 2013 7:21 pm
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