Electric Sport Bike

Objective

The overall objective of the project is to design and construct a Brushless DC motor, with provisions made for regenerative braking, such that it can be used to drive an electric motorcycle. ​This consists of conducting research to understand the inner workings of an electric motor and the mechanics of a typical motorcycle. A solid understanding of the factors that contribute to the torque produced by the motor is essential in attempting to enhance the efficiency of this vehicle. The goal would be to achieve a speed of 80 miles per hour while conserving the charge of the batteries for as long as possible.

Meeting

Monday, Wednesday, Thursday 9 to 3PM

Students

Mentor(s)

Blog

Week 12

August, 05 2019


The wire terminal positioning was adjusted.

We are currently in the process of making holes for wires on the top of the battery frame cover. Also cutting out the plate and tap holes with the BMS screw sized threads and threaded the holes.

Week 11

July, 29 2019


This week we determined the correct positioning of the screws for the battery mount and BMS mount. We also designed a mount plate for the BMS to ensure it stays in place and is less likely to move or get damaged while the motorcycle is in use.

Week 10

July, 22 2019


Manufactured brackets for the charger hold/ made 19/64 in holes for m6 screws to hold the charger in place on the frame. The remanding debris and rust left on the motorcycle was cleaned off.

Week 9

July, 15 2019


Last week we finished plasma cutting the triangular brackets and drilling the holes to screw the aluminum bars together. We then attached brackets onto the bars and put the battery mount together. Additional brackets where also made to for the charger to hold it in place on the frame.

Week 8

July, 08 2019


Last week we finished making the support bars for the battery pack

The aluminum bars for the battery mount were tapped together to once again make sure that the measurements were correctly and fitted. The triangular brackets were cut with a plasma cutter and hole where drilled into them in order to connect the support bars together.

Week 7

July, 01 2019


Obtained the sprocket and chain for the motorcycle. The group started working on the battery mount most of the week. 1/2" by 1/2" bars mounts were made out of aluminum and measured the dimension several times to make sure it would be a tight fit. Next, we worked on the measurements of the triangular brackets that would be screwed onto the aluminum bars to hold the entire battery pack in place.

Week 6

June, 24 2019


The group finished plasma cutting the front and bottom face of the motor mount last week. We then began the process of sanding it down for a cleaner appearance. We also sanded down the triangular supports for the mount and welded the those supports to the front and bottom face. Holes where in to the bottom face of the motor mount for bolts to keep the motor itself in place.

Week 5

June, 17 2019


To minimize any possible errors in manufacturing the dimensions of the mount for the battery pack. The group made additional cutouts out of cardboard to determine if the positioning and size of the bar is accurate. We needed to take the rubber insulator into account when determining the size of the battery mount, so we left about a 1/2" space for wiggle room while cutting out the pieces of cardboard.

Week 4

June, 10 2019


Today we assembled the entire wiring diagram for the motorcycle and got the motor to turn on! This is a milestone achievement for us. We noticed that the throttle was too sensitive and accelerated the motor from 0% to 100% without even turning the throttle too much. So we would need to reprogram the throttle so that it accelerated the motor more gradually the more we rotated the throttle.

Working in the machine shop, we began manufacturing the mounts for the battery pack and motor today. We created a few blueprints for the exact dimensions of all the different pieces that will make up the mount.

Week 3

June, 03 2019


The group continued discharging the batteries today, and we monitored and recorded the voltage. Mike showed the new members of the group how to use Fusion 360 for 3D modeling and had a lesson on how to create specific objects like screw mounts, wires, and casings, including new battery pack with joints.

The batteries were discharging very slowly, at a rate of 0.01-0.015 volts every hour the first two days. After the initial starting period, the discharging system was discharging the batteries slightly faster as the days went on. The batteries were expected to be fully discharged by the end of the day, unfortunately multiple cells have higher voltage indicating that not all the cells were discharging as uniformly as we initially expected.

Week 2

May, 28 2019


The group manufactured 40 connecters for the battery pack out of a large copper sheet. Upon completion of connecting all the cells together, we noticed that we had two damaged cells. Upon realization of this, we decided to take apart the battery pack and replace the two damaged cells.

We replaced the two damaged cells with two undamaged but dead cells. For the sake of safety and consistency, we decided to charge the two dead batteries first so that all the cells in the battery pack are at the same level of charge. After charging the two batteries, we re-wired the battery pack so that it would be discharged using the heating element. We connected the batteries to the heating element of placed the heating element in a bucket of cold water and waited until the batteries dropped in voltage over the course of the next few days. As the batteries discharged, we began making cardboard cutouts of the mounts for the batteries and motor. This helps us visualize and determine exactly how we plan on mounting everything onto the motorcycle frame. Also, a small Arduino circuit with turn LEDs was created.

The cardboard cutouts were finished today and this provided a better understanding of the ideal dimensions for the mount. The battery discharging circuit was also checked, at 6.6V it was drawing 15.7A (about 100W of power).

Week 1

May, 20 2019


Today we welcomed Edgar Hernandez, Adrian Ortega, Erin Brett and Ben Wenberg to the project. The new group members were introduced to the motorcycle and we discussed the plans for the summer as a group. We took the initiative to clean up the motorcycle a bit and cleaned the rust off the breaks, checked inside the pistons for water damage, and put the suspension back in. Because each one of our schedules differ, we have decided that two - three people will be working together on a specific task in order to increase the amount of work being done to complete the project. Fortunately, the size of our group has doubled since last semester and we are expecting more progress to be done on the project throughout the summer.

A safety kill switch was purchased along with fully insulated quick-disconnect terminals, steel pipe flange and a grip throttle in order to connect the general circuit. We are currently looking for a set of tires, a chain, and a sprocket for the motorcycle, however the group is currently thinking to manufacture a custom sprocket. The battery was disassembled in order to discharge the battery cells for safety reasons. The heating element was tested with motor connected in series with it. Did not heat up the heating element. However, connecting the heating element by itself to the batteries (2S-1P, 6.6V) heated it up very quickly. It was decided to connect cells 2S-24P for discharge. 6.6V was tested, and the calculations show that the pack will be discharged in 32 hours. 9 hours a day, for three and a half days.

The throttle that was purchased arrived with a couple manufacturing defects. The throttle was jamming and the wires were not extruded from the correct spot. To overcome this issue, we cut out a small hole were the wires would be pulled through and covered them with electrical tape to enable the throttle to move properly. The next thing we covered today was assembling and testing the discharging circuit. Calculations were also revised and it was found that at 10kW power usage the motor will be able to accelerate the motorcycle up to 27.5 m/s (61 mph).

Today we managed to complete the circuit connecting the motor to the controller. To construct the discharging unit, we cut holes in plywood for the Flange and was later mounted. The discharging circuit was also completed and the group is working on a graph to track and display the voltage of the battery.