The Swamp Chompers 🐊
Event Location: Cocoa-FL
Competition: Junior Solar Sprint
Division: 7-8 (JSS Blue)
School: Milwee Middle
Team Size: 4
Our Team
Team Name: The Swamp Chomps
School Name: Milwee Middle School
Location: Cocoa, Florida
Our Names: Liam E (8), Ishaan R (8), Jesus R (8), Miguel Z (8)
Our Purpose: We made our car an alligator to represent the state of Florida if we go to national competition. We feel that the ferocity and cleverness of an alligator properly represents both our team’s character and our school.
Documentation
Photos:
Photo: This photo depicts the angled view of our car.
Photo: This photo depicts a front view of our car (as if an alligator is coming directly at you).
Photo: This photo depicts the back view.
Photo: This photo depicts the top of the alligator, showing the top of the scales and eyes.
Photo: This photo depicts the bottom view of an alligator, you can see that the pattern resembles the belly of an alligator.
Photo: This photo depicts the alligator facing right.
Photo: This photo depicts the alligator facing left.
Photo: This is the angled picture of our box.
Photo: This is the top of our box, showing the name of the alligator’s habitat, “The Swamp”.
Photo: This photo shows the alligator in a swamp-like habitat. The river is flowing on the right, while the trees are on the left.
Project Log
| Date | Task | Time Spent | Team members | Obstacles encountered | Modifications |
| 3/20/2023 | Began brainstorming ideas of how to make the car what it will look like | 1hr | LE,IR,MZ,JR | Trying to figure out layout of car and gear ratio as well as theme | Made a sketch of a outlook of what the car should look like |
| 3/21/2023 | Cut out wood and painted car, attached tail | 1 hour 30 mins | LE,IR,MZ, JR | Some sizes and shapes didn’t work for the tail. | Added supports beams with the tail to hold solar panel |
| 3/23/2023 | Attached spacers, and wheels and axles. Attached motor | 1 hour 30 mins | MZ,LE, JR,IR | Had to figure out what was the place to put the axles where the car is balanced | Glued spacer and motor, as well as adding rubber bands to wheels |
| 3/27/2023 | Made and attached eyes and scales. Attached eyelet. | 1hr 15mins | LE,MZ,IR,JR | Had to sand eyes to lay flat on the base the car | Decided to add clay scales for detail as well as make a place for ping pong ball |
| 3/28/2023 | Painted box as well as finished painting car | 2 hours | IR,JR,LE, MZ | Scales were coming off, due to poor attachment | Reattached clay scales |
| 3/30/2023 | Added more detail to the box with feature making a more alligator shape | 1hr 30mins | IR,JR,LE, MZ | Had to see what parts of the box need more detail | Added teeth and letters for the box |
| 4/3/2023 | Began to work on inside of box, 3d printed new wheels | 2hr | IR,JR,LE, MZ | Had trouble on what size to make the wheel | Created an outlooks for what the inside of the box will look like, designed new wheels |
| 4/4/2023 | Attached 3D printed wheels to axle. | 1hr 30mins | MZ,JR, LE, IR | Axle piece kept sliding into wood piece | Fixed axle so it would not slide into the wood when running |
| 4/6/2023 | Tested our car with and without the solar panel, added new battery pack | 2hr 30mins | LE, IR, MZ, JR | Scale kept coming off, and painted shedded off the scale | Repainted the scale, and glued it back on |
| 4/10/2023 | Made 2 drawings, edited the website, tested with and with the solar panel (battery) | 1hr | LE, IR, JR | Had to redo the drawing because the angles were off | Corrected the angle of the alligator head and wheels on the drawing |
| 4/11/2023 | Beautified our website, and made 1 more drawing, tested our car without the solar panel | 1hr 30mins | LE, IR, JR | Some trouble with formatting our website | Reformatted and aligned the text so that our website looked good |
| 4/12/2023 | Began to make a script for video, recorded a little late | 1hr 30mins | LE, IR, JR, MZ | Had to figure what to say and how to say things | Completed intro as well as 2 of our partners parts. |
| 4/13/2023 | Filmed video | 1hr 30min | LE, IR, JR, MZ | Snout piece broke off | Re-glued snout piece. |
| 4/14/22 | Filmed and edited video | 1hr | LE,IR,MZ, LE | Audio issues in the video | Re-shot some parts of the video. |
Design Process
| Design Process Steps | What our team did |
| Define a Problem | “Design a solar powered car that is fast, durable, and innovative.” |
| Generate Concepts | We were originally thinking of making the car front wheel drive but upon further research, we changed the design to back wheel drive (to make the car go quicker). Gear Ratio: 10:50, we used this gear ratio to allow the car to accelerate faster. While making the car aerodynamic, the car’s front looked like an alligator head, so we made our car an alligator. This was convenient because the back support looked like an alligator tail. |
| Design a Solution | We used drawings to communicate ideas through our team members as well as to help us come up with better designs. |
| Build and Test Solution | We used cardboard for the tail and balsa wood to hold the panel in place. The panel rests across the beam and we have a slot in the front for the front of the panel. We also put rubber bands on the wheels to make the wheels have more traction, to make the wheels grip on the track, therefore making the car travel faster. To get the optimal amount of sunlight, we adjusted the degrees that the solar panel was resting to match Florida’s sunlight. We also designed our box to look like an alligator. The inside of our box looks like a swamp. |
| Evaluate Solution | We tested our solution by running our car on a track, we tested both battery power and solar power on our car. We observed that our car ran unevenly, so we straightened out the axles. |
| Present Solution | We will present our solution (car) on April 22, 2023 at the Energy Whiz Competition. |
Design Drawings
Drawing: This is one of our concept drawings, showing the top and the side.
Drawing: This drawing shows the top and the bottom of our car.
Drawing: This drawing shows multiple views of our car, and is the final drawing of our completed design.
Drawing: This is one of our first drawings, outlining what we are later to build.
Drawing: This is the 3D model of our 3D printed wheel. We 3D printed our wheel because our old wheels were too small (the gear was touching the ground.
Car Specifications
Width: 10.25 cm
Length: 28 cm
Height: 12.75 cm
Weight: 214g
Wheel Size: 4.5cm (diameter)
Gear Ratio: 5:1
Motor Specifications:
Rated Voltage: At 1.5 volts, the amperage is .12 under no load. At maximum efficiency, the amperage is .53. At 3.0 volts under no load, the amperage is .16. At maximum efficiency, the amperage is 1.55.
No-Load Speed: (RPM): 5200 rpm
Torque: Stall torque is 130 g•cm, 12.7 mN•m
Shaft: Shaft diameter is 2 mm. The outside dimension of the motor is 24.2 millimeters
Operating Voltage Range: 1.5 to 3.0 VDC at 330 mA
Components:
-Wheels (Recycled)
-Balsa wood frame (Recycled)
-Motor (Recycled)
-Paperclip eyelet (Recycled)
-Balsa wood Beams (Recycled)
-Cardboard Tail (Recycled)
-Ping Pong Ball Eyes (Recycled)
-Axle (Recycled)
-Spacers (Recycled)
-10 tooth gear (Recycled)
-50 tooth gear (Recycled)
-Battery Pack with switch (Recycled)
-Alligator Clips (Recycled)
-Clay Scales (Recycled)
Total Cost: $0.00
Test Results:
| Test 1 (Solar) | Test 2 (Battery) | Test 3 (Solar) | Test 4 (Solar) | Test 5 (Battery) | |
| Weather | Cloudy | Cloudy | Sunny | Sunny | Cloudy |
| Distance Traveled | 20m | 20m | 20m | 20m | 20m |
| Time Elapsed | 14.89 seconds | 9.62 seconds | 12.98 seconds | 13.27 seconds | 9.83 seconds |
| Speed | 1.34 m/s | 2.07 m/s | 1.54 m/s | 1.51 m/s | 2.03 m/s |
| Comments | The wire was too long and was rubbing up against the wheel | Car runs at a fast speed, but unevenly | Car runs faster after we tied the wires together, car runs straight | The solar panel is easily removed when we need to cut the connection | We observed that the car runs faster on batteries than on solar power |
| Ideas | Tie the wires together to make them shorter | Straighten out the axles to make the car run straight | We can glue the wheels down to secure them |
Video