Robotics Education & Competition Foundation
Online Challenges

C channel sliders

3

andycherbert
Entry ID #: 5906
Created: Sat, Jan 12, 2019 8:01 PM


The C channel sliders I have design are intended to adapt 2, 3, and 5 hole wide C channels into use as a rail for linear motion, like the current linear motion kit. I created this part as an alternative to the current linear motion kit, because I have found last year that there were many issues with friction between the track and truck, limited structural support, and other issues which caused my team's scissor lift robot to fail. This year, my team has been using the linear motion kit with ball punchers, and also has started on prototyping improved linear systems using spacers to slide C channels. I decided to try to prototype something similar, that would allow for linear movement across a C channel without the risk of the part becoming detached, and that would perform more smoothly than a slider.

The part has 4 different variations- one for 2-hole-wide C channels, one for 3-hole-wide C channels, one for 5-hole-wide C channels, and one for any size C channel. The part is designed with 4 slots where the C channel or the slider can move freely back and forth, without becoming misaligned or sliding off the C channel to the left or right. The height and width of the part is made to fit neatly around whatever size C channel it's intended for, and the square holes are spaced out the same as the standard 2-hole-wide C channel. On the long ends of the part are an arrangement of circular holes. These holes are designed to allow axels and screws to slide through without the need of bearing blocks, to save space. One could slide an axel through these holes to provide some small wheel, such as a plastic spacer, or rubber bands, which could provide additional support on the outsides of the C channel, or change how the C channel slides thru the part by adding or reducing friction. There is also room for screw nuts, so one could mount additional parts on the side. The part is connected only on the bottom and not the top, to allow for room for something inside the C channel connected to the slider, like a gear, or to allow reduced friction by reducing contact between the C channel and part. The part variation designed for any size C channel does not have any square holes, so one could use the circular holes to attach a piece onto a C channel that none of the other variations could fit or be used on. The piece might even be cut for use on an angle. All variations of the piece should be made with the same or similar plastic as spacers, to allow for little friction sliding between a metal C channel. The part could be used on a robot for a puncher, scissor lift, elevator, or any sort of linear movement. To make a basic puncher, for example, one could place rack gears down the middle inside a 2-hole-wide C channel, slide the 2-hole-wide C channel slider onto the C channel with the open side of the piece exposing the rack gears, screw on 2 plates on each side of the C channel slider, and attach a motor, axel, slip gear, bearings, and anything else needed for the moving part of the puncher, directly on the plate. Using the many different holes, one could adjust their puncher to function in a slightly different way or design as well.

In TinkerCad 4.4, I started desinging the part by downloading some VEX part models from the website to use as refrence. The part with a red rectangle. I then added some "hole" rectangles to hollow out the middle, then added more rectangle and cylindrical "holes" to create the holes on the piece. I then grouped the "holes" and the rectangle together, which carved out of the red rectangle into the part. I then decided to add slots for the C channel to slide thru, so I added some more "hole" rectangles and adjusted them into the piece based on the VEX models I downloaded. Then I moved around the holes, so they fit as close as possible to standard parts, or in the case of the circular shaped holes, so they can fit in a lock nut, axel, and something on the axel, all within the piece. I also added multiple holes, including a middle hole, to allow for additional functionality. I then expanded my base design for the additional C channel sizes, simply changing the size of the red rectangle and copying the square designs to match the VEX models.

After using TinkerCAD, I learned that the software has potential to become an easy-to-use and professional tool for anyone looking to model. I found it difficult to position parts precicely where I needed them, and having used SolidWorks, Sketchup, and other 3D modeling programs before, I think there are a lot more features TinkerCAD could have in the future. I have used the program for basic designs of my robot, and will continue to use it to make basic yet helpful 3D designs. Futhermore, I hope this year to encourage my teammates to use the software to help them out with their own robot designing. Learning 3D design software will help out in my career path because being able to design before building is essential to engineering, and outside of engineering, it can be helpful for creating a simulated 3D world such as in video games or movies. By learning about 3D design, I hope to use such skills to spread STEM to whoever I may influence, so they can be encouraged to start learning about STEM, and I think TinkerCAD is a great way to help beginners in STEM start learning and creating.