Tuesday, April 22, 2008

Taking a Break

I'd like to thank all the folks that I've bumped into over the past few weeks who have been tremendously supportive of this open-source EV conversion project. People have been quick to respond and eager to share their own experience and knowledge with Civic conversions. In the process, I've found several folks in the Portland area who are willing to help out with a variety of skills and talents.

A few things that are in the works:
  • getting the Civic S20 transmission to a precision measurement person to get an accurate diagram of all the holes and outline for repetitive fabrication of adapter plates
  • ordering a clutch plate and sending it off to EV-America for a motor shaft adapter
  • purchasing relevant EV kit parts (9" motor, etc...)
  • getting a '92-'95 Civic and start hacking away to get the battery boxes and other components laid out
  • starting on documentation for the conversion kit (tool list, parts list, etc...)
In focusing on all these tasks, I've neglected preparing for my upcoming vacation to Italy with my wonderful girlfriend. It's time to take a break, get ready for the vacation and hit the ground running when I get back. I might put out one or two more blog posts, but things will probably be quiet for awhile...

Again, I wish to thank everyone for all their enthusiasm and support during the initial phases of this project. It's a process and taking time out to drink wine and see amazing art is a good thing.

Best wishes to you all,

Playing with Kicad

I spent a few hours over the past days playing with Kicad. It has some quirks, but overall it's a great freeware schematic CAD package. I created an EV-parts library so that I could draw up schematics specific to electric vehicles. I've posted the current ev-parts library to the files section of the Civic-EV Google Group here.

Here are some of the symbols I've created for EV usage.

Friday, April 18, 2008

Playing with Google Sketchup

I thought I would take the afternoon to see if I could draw some battery boxes with Google Sketchup. I was surprised by how easy the program was to use. Here are some tentative 3/16" polypropylene battery boxes for the Civic-EV design:

This is the front (headlight) battery box that holds four batteries.

Here is the tentative firewall battery box that holds five batteries

And finally the rear trunk battery box that holds nine batteries.

All the boxes above are made of 3/16" polypropylene sheet. These are modeled after the boxes from the Porsche 914 EV I converted awhile ago with a kit from Electro Automotive. I plan on adding lids with battery hold-downs in them just like the Electro Auto ones.

Again, I was surprised by how easy it was to draw the models above. I plan on e-mailing them to a local plastic welder (Apex Industries) to see if I can get a quote for making them.

You can get the Google Sketchup files for these at the Civic-EV Google Group in the files section.

researching suspension parts

When people purchase their '92-'95 civic, the first thing they'll need to do is upgrade the suspension to handle the extra weight of the batteries. The CivicWithACord journal suggests getting Koni yellow adjustable struts and a set of Ground Control coil-overs. Ground Control sells the coil overs (SKU 4530) for $299+shipping. Make sure you request the beefed up springs, two of type 1200.250.0275 and two of type 1200.250.0200. The 1200 stands for 12" springs, the 250 stands for 2 1/2" inner diameter, and the 0275/0200 stands for the ft-lbs/inch of compression. I'm not sure where Bob Bath got these numbers, I'll have to contact him.

If you search around on the internet, you can find better deals like www.modacar.com that has the whole package for $799. Do a Google of "Koni yellow adjustable shocks Civic". You can save some money by purchasing the shocks and coilovers separately. If you search on the honda-tech.com forums, sometimes you can get a discount code that works at groundcontrolstore.com to save you significant money, but I didn't see a special for the combination I was looking for this time.

More U-Pull-It Measurements

I wanted to get some more detailed measurements, so I went back to U-Pull-It again. Here are some photos:

Here's a shot of the front engine compartment without anything in it. I'm trying to see the best way of putting batteries in the front rack. The front is 35 1/2" wide without the tow brackets, 35" wide with the tow brackets and 34 1/4" wide with the bolt heads protruding out of the brackets. If we have two batteries aligned left-to-right and two batteries aligned front-to-back in the front battery rack, that gives a minimum width of 34 3/4". With the battery rack metal parts, that adds 1/4", making things very tight.

Also the measurement from the front vertical metal for the hood latch to the clutch slave cylinder is 7 1/2". Without the clutch cylinder, the space is more reasonable at 9". If the group decides to go with a clutch-less system, that will make clearance on the front battery rack better.

Now I realize that this car may have been in an accident and the front measurements may be off, so I'll have to revisit this when we work on a purchased vehicle.

Other measurements I cared about were:
  • space between the two trunk frame supports 32 1/2" (for rear battery box)
  • space between trunk frame supports with welded joint 31 1/2"
  • approximate depth to work with for rear battery box: 24"
  • Distance between two front suspension towers: 31 5/8"
  • Distance between two bolts on side of front suspension towers: 6 1/16"
  • Distance between left front tower and brake fluid reservoir: 28 1/2"

Another thing I wanted to look into was using existing mounts from the engine to support the dangling end of the motor. Here are some shots looking at the driver side mounts on the engine:

This shows the bolts on the upper engine mount. The two vertical bolts below it hold it to the engine.

This shows another bracket that might be useful that attaches to the upper engine mount. Perhaps this is for the power steering pump.

Here is a more detailed shot of the lower engine mount on the drivers side.

Next, I'll be doing some research on suspension parts to handle the added battery weight.


Friday, April 11, 2008

Going Back to U-Pull-It - Don't try this at Home

Well, I went back to U-Pull-It today to see if I could salvage the throttle body from car #2 that I found last time and ended up with a whole lot more than I bargained for.

Here's the throttle body from the last car. I like the idea of using the TPS (throttle position sensor) on this instead of the PB-6 potbox that most people use in their EVs because I think the accelerator pedal feel will be much closer to the original.

After getting out the throttle body in about ten minutes (faster than I expected), I started looking down at the engine block and transmission. Gee, if I remove a play around a bit, I can get some experience with removing an engine.

Three hours later (ugh), the engine and transmission came crashing to the ground. After yet another hour of goofing around, the transmission fell off. U-Pull-It sold me the throttle body and transmission for a total of 145.00. This will be highly useful if I need to develop an adapter plate for the motor. Adapter plates already exist from ElectroAuto and EV America, but this will allow a local mechanic to perhaps design an open source one.

Here's the cherished transmission brought home and in the garage. To save gas, I mistakenly took the electric 914 to U-Pull-It and forgot to bring a protective mat for the upholstery. There are a few grease spots on the passenger seat floor (it wouldn't fit in the tiny trunk) that I'll have to clean up. Note to self: take the Subaru with included cargo mat next time!

Here I am after a half hour of washing all the grease and grit off my hands and arms. I haven't been this dirty since I worked on the Porsche 914 transmission for my existing EV. I really appreciate working on electric vehicles due to the lack of fluids and other dirt. Hi Mom!

I ran the meeting for the Oregon Electric Vehicles Association last night and several people seemed interested in the open-source EV kit. We didn't have enough time to break into smaller groups, but that will happen next month.

Next up: organizing the civic-ev-kit Google group to get tasks lined up.


Tuesday, April 8, 2008

Pictures from the Wrecking Yard

Last Friday, I headed out to U-Pull-It auto wrecking to see if they had any '92-'95 Civics on the lot. Fortunately they had three of them, so I took some pictures to see if it would help me with battery rack and other component placement.

You can click on any of the pictures for an enlarged version. I've limited the size to 640x480 to save disk space since there may be many photos during the course of this blog.

Here are some shots from Car #1:

This car had the whole front end cut off of it! Without the engine or transmission installed, I was able to see the components on the firewall more clearly.

Here's the trunk space. I got some approximate measurements from this.

Here's the pressure equalization flap on the left wall of the trunk that Bob Bath uses to vent the hydrogen gas from his trunk-mounted battery box.

Here's a shot under the car on the left side from the rear, just to the left of the spare tire well.

Here's a similar shot from the rear of the car but on the right underside of the spare tire well.

This shot is from the left side looking under the car at the middle of the spare tire well just behind the horizontal support member that ties into the swing arms of the rear suspension. The trunk battery box will need to sit between the two main support beams in the pictures above and behind this horizontal beam.

Another shot from the right side of the car looking up to where the fuel tank used to be in front of the spare tire well. This is just in front of the horizontal support beam that ties into the rear suspension.

A close-up of the right-front support beam in the engine compartment.

A close-up of the firewall. The master brake fluid distributor is in the middle of the picture. The firewall battery rack must not interfere with this.

A close-up of the drivers side support beam with the engine mount (right half of the picture).

Looking down at the power-steering unit with rubber booted linkage. Many people who convert their Civics replace this with a manual steering rack to get rid of the extra tubes and avoid having the power steering pump.

Okay, on to car #2: (slightly better shape)

Here's the engine compartment with most of the engine still installed.

This passenger-side firewall area is where the 12V battery used to sit. Notice the rust damage.

Here's a closeup of the driver-side engine mount. There might be some space in this nook to put something.

A look at the passenger-side nook just behind the right headlight with the main support beam. The front battery rack could bolt into this or hang off of it.

This is looking straight down on the passenger side just behind the radiator. Just right of center is the hydraulic clutch cylinder that often interferes with the front battery rack. I'm considering using a clutch-less adapter system from the motor to the transmission which would eliminate the clutch throw-out bearing and this cylinder, providing more space for the batteries.

Also looking straight down on the driver side just behind the radiator into another cavity that will hold the front battery rack.

This is the throttle assembly. The throttle cable is plainly seen in the center of the picture. Just behind the circular opening to the left is the Throttle Position Sensor (TPS) with red and yellow wires. To maintain the feel of the original accelerator cable, I'm considering making a circuit that can translate the resistance of the original TPS to the 5K resistor needed by typical EV motor controllers.

Going to the wrecking yard gave me a better feel for what I'm in for. Perhaps I'll have a field trip with interested members of the OEVA to look at these vehicles to plan the battery racks. Based on information from the CivicWithACord site, getting nine batteries to just fit in the trunk between the main support beams is going to be a challenge.

I might go back to U-Pull-It on Friday and try to remove the transmission from car #2 so I have something (albeit non-functional) to play with when considering adapter plates. At least I could try to get the throttle body and test out the position sensor (TPS).

Whew, enough pictures for one evening. Good Night.

Open Source Tools and Open Hardware License

Unlike the Gnu Public License (GPL) for software, there aren't really that many widely used open-source hardware licenses out there. The best one I could find was from TAPR (link at right). It seems like this will be good enough as long as all the designs have the Open Hardware License (OHL) identification on them.

The next hurdle was finding free tools with which to design various parts with. We basically have three kinds of data for the overall design:
  • Documentation text
  • 2D/3D drawings of physical objects (like battery racks)
  • electronic schematics for the wiring diagrams
In order to collaborate with other open-source contributors, I've started a Google Group to share messages, design files and write documentation using WYSIWYG web pages. I'm hoping the user-editable web pages will be similar to a Wiki in that any contributing member can edit them. I'm going to start with this as the documentation tool.

While I don't necessarily like using a commercially provided tool, Google Sketchup is really cool and allows people to quickly create 3D objects with annotated dimensions. The software is free from Google and it runs on both Microsoft and Macintosh operating systems. I've found that many people in the EV community prefer MacOS over Windows, so hopefully this tool will engage Mac owners too.

As far as an open-source schematic tool, the best one I could find was Kicad. This runs on both Windows and Linux and the source code is protected under the GPL open-source license. I haven't found a free EDA tool that runs on both Windows and MacOS, but the open-source nature of Kicad should allow it to be ported to MacOS in the future.

Although Google Sketchup and Kicad both store files in a proprietary format, official releases of the Civic EV kit will contain (as required in the Open Hardware License agreement) files in a commonly readable format such as .PDF Several free .PDF writers exist that I can print to just like a regular printer.

You may have noticed that I've included a bunch of new links on the right to help people get more Civic EV resources. My next step is to get the structure of the Civic EV Kit Google Group set up and invite several key people in the Civic EV community so we can get this ball rolling. I'll also be talking with folks at the Oregon Electric Vehicle Association on Thursday, so perhaps I can find some experienced people there to join as well.

While I'd like to share this information with everyone, sometimes too many "cooks" in the EV "kitchen" might cause more chaos than it's worth, so I'll probably limit the number of contributors on the Google Group for the time being.


Monday, April 7, 2008

An Easy EV Conversion Kit For People

After spending the past year and a half converting a Porsche 914 to an electric vehicle, I decided to expand my horizons by designing an open-source electric vehicle (EV) conversion kit for a commonly used car. The intention is to create detailed designs and directions so that anyone who has a garage and is moderately proficient with hand-tools can convert their car to an EV.

This project started about a month ago when I became co-chair of the Oregon Electric Vehicles Association. I wanted a project that the group could share their collective brain power and rally around. With rising gasoline prices, I believe the demand for freeway capable electric vehicles is going to increase over the next few years.

While people can purchase neighborhood electric vehicles today for about $10K, they only have a top speed of 35 miles an hour or so, essentially glorified golf-carts. All the commercially available freeway-capable (70 mph) EVs are priced way out of reach for the average consumer. Today, there are high-end cars like the Tesla Roadster ($80,000) and the Fetish ($120,000) with future possibilities from LionEV, AC Propulsion and LionEV coming up for probably close to $30K.

What about the person who tinkers in their garage who drives like the typical person (<30 miles a day) and can only afford $10K-$12K for their car at most?

With that in mind, I sorted through the electric conversions over at EVAlbum and found several cars that you could purchase for under $2,000 on the local Craigslist classified listings. In short, I came up with four options for a practical, economical EV conversion:
  • Ford Escort
  • 5th Gen Honda Civic ('92-'95)
  • Geo Metro
  • Saturn SL2
After talking with several people, I got the impression that the Honda Civic beat the other three vehicles hands-down in the selection. The Saturn came up a distant second, but everyone agreed that the Civic was the best.

Fortunately, Bob Bath down in Grants Pass has already compiled a huge amount of information on converting a 5th generation Civic at his CivicWithACord site. I ordered the CivicWithACord DVD and talked with him on the phone for a long time about all the little details. I really appreciate Bob's willingness to share his wealth of information. I hope this project furthers his vision of emission-free electric vehicles for people.

There are already commercially available kits with excellent, detailed instructions for how to convert a vehicle. Unfortunately, these kits are for much older vehicles like the Porsche 914 and the VW Rabbit. There's a kit for the Chevy S-10 pickup, but many people just want a practical car to zip around in. My goal is to create a Civic EV conversion kit with open-source tools and open-source designs/documentation so that the most people can benefit from it.

This blog is the story of my path towards that goal.

Damn the torpedoes. Here we go.