Pano Test

This is one we took on our drive along Route 101 on the Oregon coast. (Low res version)

Electric Bike project part 2

In short, It works. I actually meant to post this in August, but forgot.

Here's the pre-debug final assembly


The thumb lever is a touch far away, but still comfortable to use.


The drive side. We never actually did anything to attach the small pulley to the motor sprocket. It's just a taper press fit. We'll pin it if it has trouble, but it works so far after a few trips.


a view of the fender washer mounting method


Brian taking it out for a spin. He had some trouble, and we ended up moving the motor assembly closer to the seat to gain a small amount of tension in the chain.


The new motor position.


I don't think ther've been many problems since the last adjustment


It was alot of fun to tool around.


All in all, a good finished project. Good thing too, since I promised to buy it if it didn't work.

If I were to do this again, I might get a bigger battery pack, though range doesn't seem to be a problem. Also, Try not to have bolt heads intersecting with the chain. It doesn't work that way.

Electric Bike project part 1

Brian and I decided to build him an electric bike conversion so he can ride his bike to work. The problem with the ride normally is a gigantic hill on the way home. Our goal was to boost him up the hills, while still allowing him to bike normally (except with a heavy bike).

We based the design off of Eric Peltzer's Electric Bicycle. We modified the design to take into account a few major differences. We didn't want to weld anything, we wanted it to be cheaper, and we have access to a waterjet cutter.

Brian purchased a XYD-13 motor kit, which is a 600W motor that normally goes on a Currie Electric scooter. It came with a speed controller, and we had an option for a twist grip, or a thumb control. We also ordered a shaft, bearings, etc from McMaster Carr, and a small set of 10Ah batteries and charger. If he doesn't get enough range on the bike, the plan is to upgrade the batteries.

The motor came with an excellent one-way clutch built into the sprocket. We decided to keep this, which allows the motor pulley to freewheel while the bike is being pedaled.

Last weekend, after we had waterjet out the motor assembly frame, we spent a few hours assembling:
Full Gallery Link
The motor assembly


Preparing the output scprocket


Mounting the output sprocket


The fruits of the days efforts


Remaining items:

• modify and mount the smaller pulley
• get shorter bolts for the output sprocket
• find and mount the bike rack to hold everything up
• install the batteries, controller, and thumb control

tgimboej

or, the Great Internet Migratory Box of Electronics Junk. I've signed up in the box request section because you never know what you can find.

Things I may be able to add to boxes (pictures and more updates to come later):
Blank Circuit Boards (up to 15" on a side)
ICs of all flavors
Character LCDs
Old graphic LCDs (10+ inch)
Ubicom (Scenix, Parallax) SX chips



I probably have enough to start my own box.

Geohashing FAIL

So, I've been wanting to do a Geohash for a while now. Particularly a Saturday 4:00 meetup. So where is the meetup this Sat? only 0.5 miles from my house! Yay!



View Larger Map
However, I FAIL because I'm going to be in Renton by 3:00. I should find some way to leave a note or something.
ARG.

Seattle Regional

We had a great time at the Microsoft Seattle Regional. We placed 2nd out of 31, and we made it to the semi-finals. We had quite a few excellent matches, and I was very happy to have my friend Mike Bastoni in town to see it. I'll write more about it later, but I wanted to share this banner made by the database of TheBlueAlliance.net, which looks like a great resource for watching match videos of the events.



No video yet from the seattle event, but they are posting videos from all the events that have webcasts, and are actually only a few matches behind at any given moment. Be sure the check out the events live on webcast where possible. The Boston regional has some very strong teams at the top of the list, and a few matches in Hawaii today made it clear that there were a number of teams that had won previous regionals present.

Worlds are going to be exciting.

Gas Receipts

I had a really bad habit of just keeping the gas receipts in the cupholder in our car. I finally brought them in and started recreating my old calculation spreadsheet. I even collected all the proper data on each receipt. Amazingly, I was only missing 3 receipts over the past year, and only one was damaged.

Google Spreadsheet


Yes, I had an entire year's worth of receipts in the cupholder. It was beginning to be difficult to shove more in.

Now I just need to find my old spreadsheet to recreate the first year or so of data. I think
I am missing all the data in between, though.

Verdict:
I am still averaging 47mpg in my 2005 Prius.

FIRST Robotics

This weekend is the Portland Regional for the 2008 FIRST competition. Every year, the FIRST Game Design Committee (GDC) designs a new game for the competition. Starting when the game is announced (First Sat in Jan, usually), teams of high school students have 6.5 weeks to design, build, and ship a robot that can compete. The aim of this whole thing is to introduce students to the wonders of Engineering, and all the associated fiddly bits like accounting, planning, organization, purchasing, CAD, finance, etc. Basically, they get to be an engineering company for 6 weeks. Good teams will do all the backend planning and finance (read: fundraising) before the 6 week "build season" starts. To help get them through this (somewhat difficult) task, teams are encouraged to build relationships with real engineering or technical companies. They are also encouraged to partner with their suppliers for help, discounts, machining, etc. This is where I come in.

I am working once again with the Issaquah Robotics Society on the 2008 robot. In 2006, I was asked to cut a few parts for the team since I work at a waterjet manufacturer. Team 1318 had 4 waterjet parts on the robot that year. In 2007, we had over 40 waterjet parts, and we were able to cut many of them during a tour. The students had a great time visiting the plant, and the demonstration lab let us use the machine to cut a series of parts that were ready to mount directly on the robot. You can see many of the parts in my gallery (We are the robot with purple bumpers around the outside). Most of the waterjet parts were brackets, though the notable exceptions are all visible in this picture. All of the claw parts, the 1318 logo bracket at the apex of the arm, and the main arm drive sprocket are waterjet. Not visible are the custom shaft adapters and motor mounts in the shoulder mechanism.
At the Portland regional in 2007, we made it all the way to Semifinals without breaking a single thing once the competition started. we did have to tighten two set screws at some point. This inadvertently won us a "Cleanest Pit" award from a fellow team, since we never actually had to get tools out.



This year, we have a pretty revolutionary robot, I think. The 2008 competition (video above) has a few classes of robot that can compete; hurdler, herder, and what we call "rabbit". We are not expecting many rabbit class robots. A random survey of robots on youtube seems to agree. Our robot (with a Monty Python killer rabbit on top) is shown to the right. The entire chassis is one single waterjet plate, with all other things bolted to it. Th rabbit has over 60 waterjet parts, and most of them are not brackets, like last year. There are two of everything; custom sprockets, custom timing pulleys, motor mounting plates, copper slip rings, and a bunch of parts that I can give you our name for, but that won't mean anything (bridge plates, brush retainers, the sandwich (8 parts for each copy)).
In this second view, you can see more of the wheel modules. Each wheel module has two wheels (basically just a wide wheel) and a 6:1 ratio belt/pulley combo attached to a 3500RPM (under load) torque-y motor. each wheel module is rotated by a smaller motor, and can rotate continuously 360 degrees. this allows us to translate sideways, pirouette, drive forward, or any combination of the three.

I honestly can go on for hours about our robot and all the waterjet parts. (Reference this CAD model for a better view). But the reason I am so passionate about the FIRST robotics competition is actually really simple to explain. I graduated from high school after spending four (three technically) years on a FIRST team, went directly to engineering school, got a degree in Electromechanical Engineering, and got a decent engineering job pretty much directly out of college. (Not to mention the 2+ years I worked at iRobot while in college). The program really prepares students for the real world. FIRST isn't a perfect program, but the constraints it puts on a project are very realistic. We are just starting a new project at work that will be done in three months. It will be very fast paced, and many people have to work together to make it happen, while still managing everything else the normally do. This is exactly what I've been trained for, and this is exactly what I'm trying to impart to the students I work with. Even the equipment we make at work (the X-Y machine portion) is very similar to the robots they build. There is a central controller, some small motor controllers (amplifiers to the machining world), a few different types of motors and solenoids. Last year we had pneumatics, which our machines have. Many of the motors on the robots are even controlled with PID control algorithms, just like the equipment we make. A number of the students have learned embedded C, and all of our code is student written and maintained. All of our parts are designed first in CAD, prints are made and handed to other students to fabricate. Tolerances are discussed, changes are propagated back to the models, and the robot is assembled in a fairly controlled manner. If you didn't read the first part, then you may even think I am talking about a real engineering company.

The students in this program will graduate college and move on to deal with some of the problems facing the world today. These students will design wind turbine, more efficient cars, new space capsules, and all kinds of things I can't even think of.

That is the reason I support FIRST.

NASA kindly hosts the competition live as a webcast. Check this link on any Friday or Saturday in the next month or so to see live robot action.

You should also find and visit your local regional this year.