Post 5: Let's take those Measurements!

 Continuing on with the build, we moved onto figuring out how to connect the drive sprocket to the left rear wheel.

By having one drive sprocket, the team will go with a one-wheel drive set up. This is also a good idea because the rear axle is not fixed, and if we did drive a fixed rear axle, we would need a differential to turn each rear wheel, which turns at different speeds during small turns.

Now that we have the four wheels for the vehicle, we used one of the front disc brakes as a reference for the bolt point for the drive sprocket. By using careful measurements, we were able to find the ideal location for six new bolt holes to mount the drive sprocket to the rear wheel's disc brake mount. 

Additionally, since the drive sprocket we ordered is for a go-kart, we had to make this modification of bore size and mounting hole locations to fit the bicycle wheels.

By then using a millimeter ruler and liquid paper, we transposed the mounting area onto the drive sprocket.

We then went on to use the drill press to accurately bore open the center of the drive sprocket to fit the wheel, then drilled six new holes to mount the sprocket to the rear wheel. 

Sometimes, if we don't have dedicated equipment to perform a task efficiently, we have to be creative and create a mechanism that can still fulfill the task with a degree of safety and precision. A CNC machine and lathe would have been best, but in this case, we used some jigs, clamps and our drill press to get the needed result!

During this time, the REV team was able to prop up and finish priming and painting the frame of the vehicle in spots that were missed. At times we have to remove and prep, then reassemble the vehicle throughout the build.

  

After receiving a few new pieces of measuring equipment, the REV team began to take measurements of key parts and mounting points of the vehicle. One challenge we encountered in the build is the mounting points of the rear wheels in relation to the frame member. We utilized the new scales to take measurements of possible mounting locations of the rear wheels relative to the frame proximity. 

We are considering: a closer mounted wheel to the frame may cause less bending force on the solid axle, while a rear wheel mounted farther from the frame gives the vehicle a more accurate width of stance. In doing this, we can measure force on the axle at different mounting points, and calculate torqu on the axle with passenger weight on the vehicle.

By gathering more data, we will turn this Design Challenge over to the Ms. Mulica's Physics team members, who can evaluate and calculate which mounting location is best, in order to minimize the bending force on the axle and wheels:

With a couple of Design Challenges underway, the team will use the winter season to research and generate the best build methods and procedures for the REV!

Next up, post 6 will speak to the start of the construction of the steering system for the REV!

See you soon!