mk3eb master computer

So, I’ve decided to change my design philosophy on the innards of the master computer.

In particular, I’ve decided to embrace this whole MQ idea. I’m hoping to find a very lightweight implimentation of a message distribution daemon written in C or Cpp – if I can’t find one, I’ll write one – with a good Perl interface. Then, I’m going to have the bus feed into a topic on that MQ. A daemon will take care of logging the data sent and receieved to a Mysql database that lives in RAM, another one will take care of sending out regular polling requests to collect data from the individual nodes and a third one will take care of writing charge policies. The startup scripts will suck the mysql data off the disk and post it to RAM, and the shutdown scripts will move the data back from RAM to the disk. (If anyone is wondering why all the funny mysql stuff, it’s because I want the system to boot off of flash, and I doubt if mysql and flash devices get along peacefully).

However, I think the next logical step is to get the MK3 boards up and running and able to answer pings under the new codebase, using a KISS serial driver on the linux side. I seem to be somewhat blocked on making forward progress on this, for no reason I can identify. On the other hand, I was blocked on making progress on the car for over a year, so there is hope.

In other news, the car did a 9 mile test drive today and still seemed plenty perky when I floored it at the end. I forgot to take a resting voltage reading, so I don’t know what percentage the batteries were at when I stopped. However, we can sort of guess by how long it takes the car to charge.. I plugged it in at 4:45 and the charger is currently set for 13 amps off of the 110V feed. This works out to a paltry 4.3 amps at 330V (the median charge voltage), which means a totally empty pack would take 10-12 hours to charge. (Depending on how totally empty totally empty is – I haven’t yet figured out what a rational peukert-corrected value for the pack is. I’ve been guestimating 40AH, since they’re 56AH SLA/AGM batteries)

Today’s trip involved some serious hills, and I had Kayti in the car, so I’m thinking it was a pretty good test. If the car can do twice that distance tomorrow, I will try and take it to the DMV on Tuesday. I would be very suprised if the car didn’t have 20 miles of range, since it had between 60 and 100 on the Evercels, which were 90AH batteries.

My next house will have 220 in the garage again.. waiting for the car to charge off a 15 amp 110 circuit is a exercise in patience – I’d like to be able to use the car for several trips during the day, knowing that the charger will finish bulk charging in a hour or so between trips. That, however, requires a fatter feed.

To add to the fun, I’m actually not getting the power from the garage.. it’s coming through one of my handy 20A extension cords that I bought to power the Mackies, from a outlet on the side of the house. The garage power is pretty much tapped out running the 12 computers that are in there. 😉

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