Suspension Update and Range Modeling Intro

Last week Roberto outlined EVT's new project and how each week a different a different team member will overview the weeks progress and their personal contributions. I'm Rango and this week I'll talk about range modeling but first, the progress of the entire group this week!

Bike trailer with suspension clamp

The trailer that is going to haul our batteries is an unsprung mass so if we run into a bump or a pothole, we are sending a large jolt through the batteries as well as the rider. To prevent this, we are designing a suspension system to dampen these sudden impulses. All of the detailes of this will be better explained by someone on the mechanical engineering team, but for now I just want to share saturday's work in the shop.



The picture shows our fancy trailer and our shock mounting system. Because we don't want to drill into our trailer, the mechanical engineering team designed a neat clamping device using two 90 degree aluminum extrudes. The point is we have a working prototype of part of our suspension made from scrap material and we will soon buy material to machine the final suspension! (Again, the details of the suspension will be described in the near future)

But now, back to range modeling:

New York is a long way away from boston. A very long way. We have 230 miles of road ahead of us so it is important to know our expected battery usage, and not just in a back of the envelope sense. I'm developing a model to determine the state of charge of our system over the course of our journey. Of course, it isn't possible to simulate the exact conditions on the bike or the rider's driving style but we these simulations will lead to insight about average behavior of the bike as wel as optimal driving strategy.

So then the obvious question comes up: how does one actually model this bike system?

The model really breaks down into three coupled systems that can be coded and verified independently.

First, we have the physical forces acting on the bike. The torque applied by our motor through the wheels, aerodynamic drag, rolling resistance, change in elevation, and acceleration are part of this sub-model.

Then, there is the electrical model including our batteries, motor controller and hub motor. This accounts for the inefficiencies involved in electric motors and their control systems.

Finally, we have changes in physical conditions as we travel our route. Changes in elevation over the course of our route as well as traffic conditions fit in here.

Over the next few days I'll detail the model for each of these subsystems

EVT's Back!

hey guys!

MIT EVT is back! After EVT's adventure in the Isle of Man it was time for EVT to look for new frontiers! During summer of 2012 the planning for 2012-2013 EVT started. Lennon and a couple of new guys started working on a project that would test our Electric Vehicles in a new way: extreme range. Our current challenge is to travel from Boston to New York City in a single battery charge. While the eSuperBike demonstrated that we can build EVs that travel extremely fast for a short amount of time, the BOS-NYC project will demonstrate we can put together vehicles with an extreme range.

~230 miles to NYC!

EVT had a very successful recruiting session during the beginning of the fall semester and we are proud to have over 10 active members contributing to the new project. (Photo of the team coming soon!). Each week/couple of days a different team member will be updating the blog with his/her contributions to the project. For today let me give you guys an intro to the hardware what we'll be using.

The plan as it stands is to put a hub motor on a bicycle which will be hauling a trailer full of batteries (120kg of batteries to be exact). We will be reusing the eSuperBike batteries (about 12kWh of energy, for comparison the 2013 Chevy Volt has a 16.5 kWh pack). We have already purchased an adequate trailer, here is a picture of it attached to my personal (non-electric) bicycle.

As for our bicycle, we have been fortunate enough to be put in contact with Geoby, a company that fabricates great electric bicycles. They were kind enough to lend us two of their models to experiment with. We'll be modifying the bikes in the next couple of weeks/months to get them ready for our NYC trip.

Thanks Geoby! (for more info on Geoby bicycles please visit: http://www.geobyev.com/en/index.aspx)

An extremely important aspect of our project is the modeling and energy budgeting aspect. We have a subteam working specifically on doing numerical simulations and path optimization for the final trip. They soon will be making a blog post about their work! We estimate that we should be able to "launch"  the EV sometime during the spring season (when is gets warm again!).

I hope this is enough info. to give you a good idea of what we are trying to accomplish with EVT this season. If you have any questions about the team, sponsorship or how to get involved please email:
 evt-contact@mit.edu.

Have a great weekend!

-Roberto for EVT

Video of eSuperbike at the Isle of Man

I Believe I Can Fly . . .

Check out the rest of the posts below to see the history of this project, start-to-finish. If you think that what we're doing is cool and would like to help us 'touch the sky' on our next build, we kindly accept your support. This helps us with everything that the main sponsors can't provide, such as random electronic components, specialized tools, equipment for our shop, flights to our events, etc... Secured, tax-deductible and handled by MIT, the link is here.

Isle of Man - Day 15 - Thank You!

The race is over, eSuperbike is packed up and waiting to be shipped back to Boston, and the MIT Electric Vehicle Team members have split off in all directions towards various summer adventures. The experience of building an electric motorcycle and racing it at the Isle of Man was amazing. The words and pictures here truly don't do it justice. Before we sign off and this blog goes quiet again for a while, the team would like to say thank you to our sponsors over the two years of this project.

THANK YOU...

...to BMW for the motorcycle frame, and even more so for the CAD files which allowed us to design the bike electronically before any parts were actually fabricated.

...to A123 Systems for building a custom battery pack to our specifications; for countless e-mails and phone calls as we trouble-shot our system and tweaked it for racing; and for coming to the rescue when we realized that only you had the paperwork needed to ship our batteries to the Isle of Man. In particular thank you to Yet-Ming Chiang, Brian Moorhead, Jerry Gohl, Doug Moorehead and Mobashar Ahmad.


...to Rahn and Mark at Rahn's Motorcycle Engineering for hours of time on the dyno without which we never would have understood our motors; and for the general support and encouragement of the team. Their relentless support was extremely encouraging and kept us going during rough times.

...to the MIT Energy Initiative, Transportation @ MIT and the MIT Mechanical Engineering Department for extensive financial support.



...to The Edgerton Center for an incredible workspace, access to tools and equipment and your general support of student teams at MIT. (the picture is of our bike in the back of the Edgerton Center pickup truck)

...to the Singapore University of Technology and Design (SUTD) and the International Design Center (IDC) for general support of student groups and new initiatives. Thank you in particular to Pofessors Dan Frey and Sanjay Sarma for your long term commitment to the project.

...to Derek, Scott and John at Boston Moto for the opportunity to test our bike during their track day at the New Hampshire Motor Speedway, and for your technical support and introduction to the world of motorcycle racing.
...to Mark at TurnOneGraphics.com for all of the extra work you put in to make our graphics look so good, and for your support and advice during our track day in New Hampshire.

...to Dave at Evomoto in Ramsey for always fitting us in for those final dyno sessions as we kept rebuilding our motors in the days leading up to our race.

...to the following companies for advice and equipment support as we brought our project to completion:
- KillaCycle Racing
- Kelly Controllers
- Boulder Electroride
- Woodcraft
- Lynch Motor Company
- Sharkskinz

Last but certainly not least, THANK YOU...

...to Allan Brew for piloting eSuperbike around the course safely (and faster every time), allowing us to take over your garage as a workspace, and generally introducing a bunch of newbies to the world of the Isle of Man TT.
...to Jan Brew for your wonderful Manx hospitality and English tea, and for allowing us to both take over your kitchen and send your husband out for more stress-inducing laps of the TT course.


From me personally, it's been an incredible ride both literally and figuratively. Thank you to the rest of the MIT Electric Vehicle Team for your hard work on the project both before and after I showed up on the team (Will, Manyu, Brent, Dianna, Dan, Romi and Mateo), flexibility when the team made tough decisions (Erick), dedication when the typical time constraints of MIT kicked in (Randall), focus when the going got tough (Radu), and for vision in the early days, innovative technical ideas in every aspect of the bike and relentlessly keeping the team on track (Lennon). It's been great working with you and we should all be proud of what we accomplished.

-Mark

Isle of Man - Day 13 - Race photos

The weather was better on the postponed race day (Thursday), and the team drove down to the grandstands for the race at 3:30. Then the race time was shifted again, not weather this time, but because of shifting the order of events. So we waited.

Eventually, it was certain that the race would go off at 5:15. Nine teams went through tech inspection and set up in parc ferme.

eSuperbike received its' third and final tech inspection sticker.

Once again teams had a chance to wander among the machines (well, among the ones that weren't in their own little tents anyway).

Photographers roamed around snapping pictures of bikes...

...and teams.

Allan was interviewed on local radio.

Finally, at about 5 o'clock, the marshals let us up onto the track to the starting grid.

Once again the bikes lined up in order and were sent off at 10-second intervals.

No wheelies here, just a smooth start down Bray Hill.

And then we waited.

By this time we had discovered the TT Live website, where we could track bikes as they pass certain checkpoints on the course. The iPhone came out as soon as Allan was out of view.

Something got jumbled though, and Allan was listed as riding through the Sulby Speed Trap at 102mph, which is faster than eSuperbike was allowed to go! We'd limited the motor controller voltage in order to protect the motors, so something must have been wrong with the course's timing system or our transponder.

Or was something wrong with the bike? If Allan was actually going that fast, then the motors were sure to burn up and fail and we'd be out of the race. But nothing's gone wrong like that before. But why is the number so high? All we can do is wait.

We could tell from the website (watched from an iPhone) that a couple of the teams didn't make it through certain checkpoints. On a 37.73-mile course, the worst part about watching a race is the limited information you can get about the bike and rider while they're out on the course. But Allan's name kept showing up on the screens for each checkpoint: Ramsey Hairpin, The Bungalow, Cronk ny Mona...

And then we finally saw them.

Fouth place!

Allan did the course in 28 minutes and 35 seconds, with an average lap speed of 79.1 mph. He and eSuperbike were faster every time they went out on the course.

The team was all smiles when he came back through the pits.

Lots of congratulations all around on a job well done.

Congratulations to MotoCzysz for taking first and second place, and to Kingston University for third place and the university prize.

The most surprising outcome of the race was MotoCzysz not getting the 100mph lap. Their two bikes drafted off of each other for most of the race to save energy, but the faster of the two only managed a 99.6 mph average. So close! There is a GBP 10,000 prize for the first electric bike to break the 100mph barrier, and it's still up for grabs.

-Mark

Isle of Man - Day 13 - Fourth Place!

Final stats:

1st place - Michael Rutter - Moto Czysz
2nd place - Mark Miller - Moto Czysz
3rd place - George Spence - Kingston University
4th place - Allan Brew - MIT
5th place - Yoshinari Matsushita - Prozza

32 - teams entered
16 - teams confirmed
5 - teams qualified
9 - teams started (including teams who did not meet official qualifying standards)
5 - teams finished

The team is very happy with the result. We were the fastest first-time entrant and one of only four bikes to complete both qualifying laps and the race.

Photos coming soon!

-Mark