Electric Echo Blog

I have to admit I cringe every time an article about a 3 wheeled electric vehicle appears in the media. I immediately imagine the vehicle being ruthlessly savaged by automotive “journalists” as; too slow, too unstable, too small, too dangerous etc, etc.

To me, these sorts of vehicles hinder the positive promotion of EVs to the masses. It’s understandable why some EV designers are attracted to the three wheel option, their light weight greatly extends the range of a battery pack and they often circumvent difficult legislation not applied to “motorcycles”.

So when the Green Car Congress posted this article about the VentureOne my pulse rate slowed as usual but the comment count was more than I expected so I decided to see what all the fuss was about…

Well it turns out that to drive this vehicle is to feel like you are flying it because it leans into the corners. It gets some huge wraps (”…the most fun you’ll ever have!”) from the hugely popular folks at Top Gear (admittedly they were driving the petrol version). This is something to get excited about because EVs need to be seen as fun to gain even a small foothold in the mass market. Take a look at the Top Gear videos at the Venture Vehicles Website and see how much they enjoyed the low level flying!

It’s been a while between posts because I’ve rewritten this one several times, just can’t seem to find the balance to keep it interesting for the technophiles and those a bit more perplexed by elec-trick-imy. So apologies if this doesn’t hold your interest…

The Issues

1. My lead acid AGM batteries will be damaged if overcharged.
2. I want to collect data about my batteries, while driving and while charging.
3. I want everybody to see my data, live on the web - if possible!

The solution

A computer that;

1. monitors all the individual battery voltages (12 x 12Volts).
2. monitors the battery pack current.
3. shuts off the battery charger if any battery is over the recommended maximum voltage (14.7V).
4. applies a temporary load to any battery that appears to be charging quicker than the rest.
5. stores the collected data onto a removable memory card.
6. streams the live data to a standard serial port.
7. is very configurable.

The progress

So far my friend and brother-in-law, Mark Philips has done a fantastic job of putting together a little AVR micro controller board that does all the logic stuff required for the above.

His micro (well, it’s mine now!);

1. has an SPI interface that talks to my 16 channel A/D MUX for individual battery monitoring.
2. has a basic 80 char two line display.
3. sends the data collected from the MUX out on a RS-232 Com port.
4. saves the data collected from the MUX onto a SD memory card in CSV format.
5. has an ISP port for simple reprogramming of the micro.
6. has its own real-time clock.
7. has another 13 programmable pins to do lots more I/O stuff with!

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