Mounting the Motor on the Long Bike

Through the process of cleaning out the shop downstairs in N51, we unearthed the remains of Longbike- an exciting artifact from back in the first year of the EVT special section of the MIT 2.007 class.  Charles Guan, EV guru and current teacher of the 2.00gokart section, mentions the Longbike and the history of the old EV section on his blog: http://www.etotheipiplusone.net/?p=3035#section3

From Charles' blog, I dug up a picture of the Longbike in its original condition from the class:

Compared to its salvaged state after some time setting around: 

Pretty much the same, although a bit dusty after its hibernation.  As my experiences in the AIBD class have made me determined to never let a good (or bad) bike go to waste, I took it upon myself to revive the Longbike and bring it back to its glory days!  It definitely had an interesting geometry, and I was curious to see what we could do with it.  

When Jack, the shop manager in D-Lab who first got me into the bike hacking scene, saw this bike, he couldn't get over the ridiculousness of how it was set up.  He got a real kick out of how low the seat was, saying that we'll have to get a pair of motorcycle racing pants and move the pads from the knees to your butt so that it doesn't drag on the ground and so that you look like a baboon while riding it.  This has discussion has led me to always refer to it from now on in his presence as the Ass-bike....  

Here Austin tries to get used to balancing on the unconventional bike geometry:

Jake (my fellow EVT UROP for the summer) and I have been trying to test out some different motor setups and controller combinations that we can use to teach new members in the fall about how EV systems work, so we figured we'd throw something on the Longbike to see how it runs.  I ended up going with just a basic, brushed DC motor controller rated for 24v and 40amps.  I used that to run the motor from an eGO Cycle2 (24v DC, 2HP).

We made an 8S2P battery pack using the 3.3v LiFe cells to power the 24v system, then I just had to mount the motor.  

I used the laser cutter to quickly mock up a mounting plate for the motor, with just the bolt hole pattern, openings for the fan and axle, and slots so that it can slide to tension the chain.  Then I quickly cut out the original plate to make room for the motor, leaving enough of the plate on the outsides to drill 4 holes to which the motor mount could be bolted.  

Then I just had to add a sprocket to the motor shaft to connect with the intermediate axle above the motor that is used to compound the gear ratio.  I found an appropriately sized sprocket to give me about an overall 8:1 gear ratio, and finally got to use the new equipment in the shop to open up the hole such that it fit on the shaft and then add a setscrew.

Then I just bolted everything all together, and the slots on the motor mount fit appropriately so that the size 25 chain was easy to tension.  I've been meaning to make a more substantial mounting plate, but for now the wooden version has been holding up well enough through all the testing!

Then once we had everything mounted appropriately...I realized that I had an extra hub motor! And what could possibly be better for the bike than 2 wheel drive??? So the 27" brushless hub motor is only rated for 36v and 250w, which is perfect for the Chinese ebike controller that I had been using on the drift trike.

As much as it hurt me to pull the controller and batteries out of the spaghetti mess of wires inside the drift trike, it'll finally force me to get a better controller for the drifter.  Plus, the hub motor ended up looking pretty good on the front of the Longbike.  We connected the throttle signals together so that the one throttle controlled both the front and rear motors at the same time, giving this bike record out of all the bikes I've made of the most power for the least stability.

Then that was the final setup, a slightly ridiculous combination of 2 controllers (brushed & brushless), 2 battery packs (24v & 36v), and 2 different motors.  Between the steep angle of the head tube and the position of the rider, it was fairly difficult to ride in this state and gave Jake some trouble as he raced up and down the hallway.

Summertime with the MIT Electric Vehicles Team!

I can't believe that I haven't posted anything since January, but I'm going to get back to regular blog posts about my projects and catch up on everything that's been going on! It's been a busy 5 months, but now I'm done with another semester and getting ready for a summer of research with the Electric Vehicles Team!

We had a very productive semester with the team including a successful trip to Providence on our electric trike and recently the crew got the converted electric 1976 Porsche 914 registered and road legal! I'll be sure to post all the work we do for the summer, and definitely check out the team blog and website!!!

http://www.mit-evt.blogspot.com/

http://web.mit.edu/evt/

Lions and Tigers and Bears, Oh My!

Having a lot of project based classes this semester made for a quick round of final exams this semester, and I was soon back at home in the sticks.  Yet during finals week, there was some commotion back home as the family informed me that the chickens were under attack.  Dad had gotten them for eggs, but once my sisters gave all of the chickens names, we've come to think of them as more of our pets and such problems are regarded as a bit of a big deal :)

So it appeared that the chicken coop had been facing an intruder, and a single chicken was taken from the coop two nights in a row.  The white fence in the picture below got completely ripped open from the top to the ground.  It's tough to see it in this picture since I took it after my dad and sister had already covered the hole with a couple layers more of the black vermin wire.  The chicken coop has its own door in the back, which opens in the back out into a small area that is fenced in on all sides as well as the top and opens at a gate to let the chickens out.  What happened that night was that the door to the chicken coop was left open, and although the gate of the fence was all closed up, something was able to rip through the fence and take one of the chickens.

The Mended Fence

The gang reinforced the fencing and had the chicken coop on lockdown the next night, seemingly ready for deterring whatever might come back again from the previous night, only to find out the next day that something had ripped the entire wall of the coop with the chickens' nesting boxes right off and taken another chicken.  

                                   

The next night there were no problems in the chicken coop, and when I got home from school the next day, we set up the trail/game cameras.  The fam had been watching a lot of the show "Finding Bigfoot" on Animal Planet lately, so they knew the drill haha.  There was never any shortage of wildlife in the rural area in which we live, and the game cam had picked up all sorts of deer, foxes, raccoons and such in the past, but we were interested to finally find out what could have possibly done that kind of damage to the chicken coop.  

The investigation continued with raccoons being the primary suspects, as they were known to frequently kill chickens and had regularly been around our property, such as the one in the picture above stealing birdseed from the feeders at night.

Dad and I threw together a quick trap using scrap wood and covered with that black vermin wire.  Basically, it's set up so that there's a door hanging above the entry and when a creature enters and goes to eat whatever food is on the inside, it bumps the dowel with the pin holding up the door so that it slams down behind him.  With an 18"x18" opening, it was big enough to catch a pretty sizable raccoon.  

I don't know if it was the long winter finally ending and letting every creature of hibernation at once, but we had a wide variety of all different raccoons and foxes caught on the camera at every hour of the night, such as the raccoon below at 4 in the morning.  The chickens remained unharmed for several days though and it appeared that the nighttime critters on camera were only there for the apple, peanut butter, and chicken wings that we left as bait rather than trying to kill the chickens.

We had caught a couple of them one day, but they had managed to overcome our efforts to trap them by biting through the wire and squeezing through a narrow opening between the wooden slats.  The fact that the raccoons were able to break through the trap so easily seemed to indicate that they would also have been able to break in through the chickens' fence just the same, although nothing had been bothering the chickens since.

Then one week after the first chicken had been abducted, the game cam picked up something much larger than just the raccoons....