Detailed Design

Overview

The goal of our system is to teach children about ramps in an educational and fun way. We decided the best way to do this is by giving the children a large flat vertical surface where magnetically attached ramps can be manipulated by the children in order to achieve variations in angles or lengths of their ramp systems. Once the ramps are adjusted to the children’s liking, an object can be gravity-propelled down their ramp system and they can observe how the falling object interacts with the various ramps.

The system is safe for the children to interact with; we verified with the child center that the smaller sized objects are safe for the children to handle, and would not pose a choking hazard to them. The entire ramp system can be wiped down with a common household disinfectant which should reduce the chances of spreading illness without compromising the components. The whole system is very durable and should hold up for many years. Any pieces that do break or become worn down are able to be replaced by the client.

Track Pieces

For the track pieces, we decided to use Cardboard Tubes/Shipping Tubes of varying diameters. See the image below in Figure A for examples of our tracks.

We found cardboard tubes that worked perfectly since they weren't too big and were fairly light. We also found similarly sized shipping tubes that we utilized as well. Some tubes were cut in half lengthwise, to create two half-pipe ramps. The cut, raw edges were sanded smooth with fine grit sandpaper to make sure everything was rounded and even.

To make the ramps look more aesthetically pleasing and a little more durable, pieces of decorated scrap-booking paper were cut to size for the individual ramps' inside and outside surfaces and then glued on using Mod Podge (non-toxic).

Then, to cover the raw edges of the ramps and to protect them, colored Washi tape was placed along them and secured with a layer of Mod Podge. Another layer of Mod Podge was applied for protection. Finally, to complete them, a few layers of Mod Podge Clear Acrylic Sealer (non-toxic when dried) was applied to make them smooth, shiny, and more durable.

20 of these track pieces in varying lengths, sizes, and colors were made. This way we are able to have 10 per side on our double-sided frame.

Connector Pieces

In order to attach magnets to the tracks, we 3-D printed pieces that are curved on one side to match the arc of the cardboard tubes' exterior. The other side is flat with a circular hole cut into it the size of our magnets in order to allow the magnet to lay almost flush inside of it. On the bottom of the flat side is a slight lip that helps the magnet that sticks out slightly from the hole lay flat on the sheet metal. We printed 40 of these pieces in order to have 2 per track and match our 20 track pieces. Pictures of these pieces can be found below in Figures B through E. These pieces are attached to the track pieces using 2-Part Epoxy ensuring that they will stay on. The magnets are also glued into the hole using the same 2-Party Epoxy.

Vehicle Design

For this design, we need vehicles to go down the tracks. We have found fun sport themed ping-pong balls which Sylvia has approved to be the correct size. We also purchased small plastic cars. All of these vehicles have been tested and are able to go through the pieces that we have well. We picked these vehicles because of their weight, they are light enough that they will not have an effect on the individual track's position as they go down the run. We also picked them since they were fun, bright colors and this makes it overall more aesthetically pleasing and more stimulating for the children. View images below of our vehicles in Figures F and G.

Magnetic Wall Structure

We attached two 48” by 36” sheets of galvanized steel to MDF wood (medium-density fiberboard) with laminate glue. We added two sheets onto the board making the structure to make it double-sided. This allows for more children to be able to interact with the board at once and have separate areas to play.

We had multiple options of how to create the frame sketched out below in Figure H-1 but we ultimately decided that the third option would be the best for this double-sided frame, after getting confirmation from Bill in the Machine Shop. The frame is made out of six 2 x 4's with a 3' long base. Four more 2 x 4's with 45 degree angled cuts at the ends are placed on the sides connecting the vertical part to the base of the frame. This gives the frame more stability and keeps it from rocking back and forth. Figure H-2 below shows the structure of this. The MDF wood with the attached sheet metal slides into grooves cut in the inner side of the vertical 2 x 4's and has a 2 x 4 on the top keeping everything in place.

Underneath the legs, we attached rubber foot stoppers in order to help avoid any of the screws or wood scratching up their floors. This can be seen in Figure I. We chose this over wheels so that if a child were to lean on the frame it would not slide out from under them. Additionally, there are no wheel-locks that may potentially break or pinch a finger should the children choose to investigate them.

We then assembled all the pieces and sanded down the whole frame in order to make it smooth and less likely to give children splinters. We also added flexible rubber padding over any of the exposed screws in order to protect the children from getting caught on the screws. We then wiped down everything with water and rubbing alcohol ensure it was clean and ready to go.