Whether on hot summer mornings when the cross country kids hoard the track or during the frigid winter workouts of the track team; there are always people who are running faster than everyone else. What happens when they run into another? Do the faster kids go around the slower folk? Or do the slower runners part for their teammates? What can be done to avoid these collisions? We could assign different lanes to each group, but still, people will spread into different lanes to avoid tripping over one another. We propose to add a system of LED’s to the track at regular intervals to alert runners on the track when a faster group is coming up behind them. This solution will benefit the track team because runners can spread out evenly among the track, and only have to make room for another group when they see an LED turning on; the group behind will also not have expend energy they can use towards running to yell “Track” in the middle of their workout.
Step 1: Materials and Tools
MDF (Medium density fiberboard) 12.5in/12in (2 boards needed)¼ in thickness Polystyrene 1 inch thick 35in/16.5in
MDF (Medium density fiberboard) 12.5in/12in (1 board needed) ⅛ in thickness
8 Red LEDs 5mm
8 Green LEDs 5mm
42 Jumper Wires
16 Toggle Switches (SPST)
16 330Ω Resistors
2 10KΩ Resistors
Construction Paper (white)
Hot Glue Gun
Hot Wire Cutter
Step 2: Cutting Out the Track
We cut the track out of polystyrene in three segments, the first segment representing the straight-away, and the other two identical sections representing the curve of the track. The first segment was cut to the dimensions 36.5 cm by 42.25 cm, the section should end being a rectangle using the miter attachment on the hot wire cutter. The next two sections are cut on the hot wire cutters as well but they are not straight cuts, so first measure where the cut is to be using either a compass, or a string tied to the end of the pen to create a radius of 18.25 cm. To cut the second sections we made a circle and then cut it in half, but each section can be done separately. The cuts are easiest to do free-hand on the hot wire cutters.
One of the biggest complications is that the size of the track prevents use of some of the tools to cut the track. For example we were not able to use the miter attachment of the hot wire cutter because the track would be to large to take off before the cut was finished. Because of this most of our cuts were freehand.
Step 3: Glue Paper to the Track
First tape three sheets, (or more if needed), together to cover the top of the track. If the track pieces are not glued together at this point in time glue them together. Place the paper on a flat surface and lay the track on top of it so that it is fully covered. Draw a line around the base of the track onto the paper. Cut out the paper and glue it to the track.
Step 4: Make It Look Pretty (also Known As Paint)
Measure where the track will be on the paper, (come in from the edges 3.75 cm), for the straight-away draw a line, and for the curved sections use either a protractor, or the earlier method of a string and pen; paint the inside of the circle green, later when the paint is dry paint the outside black.
Complications: The green of the track was put on first and the black second, but there were splotches of black that got smeared onto the green section.
Step 5: Ready Everything for Electronics
At this point everything is assembled except for the control panel and the circuit. In order to make sure the circuit is put in the correct place measure starting from the representational finish line. To find where the LED’s on the curve will go draw a line at the halfway point between the two straight sides of the track, then measure two centimeters in from either lane where the LED’s will be placed. If the board is too thick hollow out a section on the opposite side of the track.
Step 6: Control Panel and Score Boards
Using a bandsaw cut out two 6x5 inch plywood pieces, 2 5x1, 2 5.5x1 inch plywood pieces, 4 4.5x1, and 2 4x5 plywood pieces.Then take one of the 6x5 and glue the 2 5x1 and 2 5.5x1 pieces around the border creating a box like shape. Then get the second 6x5 piece and using the drill press, drill out 16 holes with a .390 drill bit, 8 holes equidistant from each other on each side to resemble the holes for each of the 16 switches that will be used to operate the circuit. When you finish putting the circuit into the box glue the top on and make sure the switches poke out of the holes that were cut using the drill press. For the scoreboards use the 4 4.5x1 and 2 4x5 pieces and glue 2 4.5x1 pieces to the end of a 4x5 piece do that for both 4x5 pieces.
Step 7: What to Do With Extra Material
If you have scrap material left from the foam that cannot be used for anything else, and extra wood from the control panel, and a wooden skewer sitting around what do you do? Well you can choose to do what you want, but…
Step 8: Prep Track for Wiring
Drill holes in the spots for LED’s and measure and cut wires so that they can reach the center of the track. Then tape wires to their spots on the non-painted side. Color code wires according to their electrical charge, then solder wires to LED’s and tape them down again to their assigned spots. Put control panel in the center of the track on the painted side and drill holes through the control panel and the track. Put electrical tape on the soldered connections of the wires.
The Circuit: The circuit consists of 16 similar series circuits placed in parallel. The series circuit consists of a switch, a jumper wire, a resistor, an LED, and another jumper wire connected in that order. There are 8 red LED circuits and 8 green LED circuits.
Step 9: Wire Up Track
Create each of 16 individual circuits. Color Code wires, for example: green wire, resistor, LED, Black wire. (make sure wires are of an appropriate length.)
The first section of the Circuits assembly process was to construct the dry circuit, we realized that first constructing the circuit in pieces would be simpler, so we made 16 different “LED Strands” one for each colour for each hole. Each strand consisted of a Green or Red negative jumper wire, cut to a length appropriate to the distance from the hole to the control panel, a 330Ω resistor, an LED, and a black or orange positive jumper wire of equal length to the negative jumper wire.
Step 10: Control Panel
Using a bandsaw cut out two 6x5 inch plywood pieces, 2 5x1, 2 5.5x1 inch plywood pieces. Then take one of the 6x5 and glue the 2 5x1 and 2 5.5x1 pieces around the border creating a box like shape. Then get the second 6x5 piece and using the drill press, drill out 16 holes with a .390 drill bit, 8 holes equidistant from each other on each side to resemble the holes for each of the 16 switches that will be used to operate the circuit. When you finish putting the circuit into the box glue the top on and make sure the switches poke out of the holes that were cut using the drill press. Drill four holes in the corners of the bottom of the control panel with a .372 drill bit. Glue it to the center of the track, or where desired. Thread all wires through the holes in the control panel, from underneath the track.
Step 11: Finishing the Circuit
Place wires through the holes so that only the LED is seen there should be one of each colour in each hole. Make sure that the LEDs placed in each hole are the appropriate length so as to reach the center of the track.
Solder all of the similar colors together (all black wires coming from the LEDs to the control panel) on the end leading to the positive terminal. The wire connected to all of the positive jumper wires can be taped to the power source. Place all switches in the control panel holes, wire the switches to have the opposite color (green wire) going to one terminal, and have the other terminal all be connected to the positive terminal of the battery.
Step 12: Reflection
Our project worked to solve a problem that track athletes face all the time at our school. While it is still necessary that someone has to watch the track and man the control panel, we found a solution that might fix the constant traffic jamming during practices, while also keeping everybody moving at a similar speed they would have been running at. This ability to fix a problem that we directly face was one of the coolest things about this project to us.
The control panel was on of our most limiting factors, we ultimately ran out of space in the control panel. The fact that we were trying to fit the wires, battery and switches all in the same place, and that they all were crossing one another in inefficient ways is likely contributing to the Red LEDs not lighting. If we could start this process over we would create a guide for the wires leading into the control panel, we would also raise it so there is more space to work with. How we would have done the guide is to stack plywood so that the wires have a groove to fit into, and when wire connect the grooves would combine and end together. Another benefit to the groove is that we could place it under the track then drill a hole only where the wires would cross to connect to a switch or power supply. This would allow for a much more efficient use of space below the track, a much more organized way of connecting and keeping track of wires, and it would allow for a power supply to be placed in the control panel above the track without it pressing up on the lid, also it would allow for a way to connect the power supply to the wires without taping it together. If we had to redo this project we would have prioritized making a grid in the foam board so that each wire could simply be placed in its corresponding spot instead of having all of the wires jumbled together in four different holes leading into the control panel.