Introduction:
MiniScience's Solar Racer activity introduces students to alternative energy
concepts while incorporating problem solving, design and modeling. In addition,
students will experience using hand tools as they construct their solar vehicle. |
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Students can explore:
- Propulsion types and drive concepts
- Basic soldering techniques and electronic concepts
- Alternative energies like solar power
Teacher Preparation: During construction of the solar racer vehicle, students
can experiment and
comprehend methods of power transfer, soldering (optional), gear alignment and calculating
gear ratios. It is up to the teacher to make sure this background information is
provided to students in some manner.
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Background
The federal government has encouraged alternative forms of transportation due
to a limited supply of oil and increasing environmental pollution. Solar cars
are just one of many transportation concepts emerging. Solar cars use solar cell
panels instead of gasoline as the fuel. As a result, exhaust fumes and oil
consumption are eliminated.
The solar cell panel generates an electrical charge that is stored in a
battery and used to provide energy as the vehicle is driven. The lighter the
vehicle, the less energy used and the farther the vehicle will travel. In cloudy
days, or at night, energy can be drawn from reserve batteries. In the future,
charge stations will be located on the road sides for quick battery charging.
Materials Checklist:
Before using the kit please make sure you have all the items listed below.
This kit has the supplies to build at least one type of solar car model. Solar
cars may be propelled using a pulley/ rubber band method or some types of
interlocking gears.
- Solar Cell
- DC motor
- Rear Slicks 1 9/16" diameter x 5/8" wide
(1/2" wide for geared slicks)
- Front Wheels 1 3/8" diameter
- 1/8" dowel for axles
- Traction Bands (for non-geared slicks)
- Eyelets or washers
- Straw
- Wood Sheet 5" x 2" x 3/32" (or
larger, so you can cut to any size)
- Basswood 5mm x 5mm x 20cm stick
- Motor Mount (With straps if needed)
- Procedure Sheet
Propulsion Systems:
Propulsion systems include using a solar cell and toy motor with a:
- gear drive
- Pulley and Rubber band drive
Advanced students are encouraged to experiment with different size pulleys,
and gears if available.
Basic Tools Required
These items may be required to build the solar vehicle:
(You can make your solar car model without them as well)
- craft knife, used to cut or
trim soft wood.
- White glue, wood glue or glue gun
- Soldering Iron, needed if you
need to solder wires.
- Pliers, used to connect and
twist wires together if needed
- rulers, used for measurements
- Pencil, used for marking
Safety Recommendations
During the construction of the solar vehicle, the following safety
precautions should be observed.
- Wear safety glasses
- Use care with sharp cutting blades
- Avoid touching the tip of the glue gun or soldering gun
- Put safety first
Competition Categories
Competition between students can be based on design, drawings, final
appearance, distance-traveled, speed, etc.
Races can be held between cars that have similar or different types of
propulsion Systems.
In addition, teachers could implement a problem-solving category for advanced
or older students. Teachers would provide students with the solar racer kit then
instruct students to make use of additional materials in the classroom to
construct a customized solar vehicle. additional items could include wood
scraps, stickers, paint, CD, colored wheels and more. How elaborate or complex
the solar cars are depends on imagination and resources.
Standard Assembly Steps
Make your solar car model in 3
simple steps.
Step 1: |
Construct the basic car chassis with 4 wheels
Cut a strip of
wood that is 2" (5cm) wide.
Mark the location
of axles by drawing two lines, one on each end of
the car, parallel to the front or back side.
On the axle lines,
mark two points that are 1/4" (6mm) away from each
side. Insert one eye screw in each of the points.
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Eye screws are
used to hold the axles. Insert the axle and make
sure it is level and it can spin freely. If
necessary, adjust the eye screws. |
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Cut some plastic
tubes or straws and use them as the spacer in both
sides. |
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Insert the wheels.
Wheels may be inserted while the axle is in
position. |
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You can also
insert the axle into one wheel and then pass it
through the eye screws. |
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At the end your
simple car will look like this. You can use it the
way it is or you can turn it over as shown in the
picture bellow. |
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In the model shown
here, the gears are built in the rear slicks (rear
wheels). With plain wheels, you had to insert a
pulley or gear in the same axle with one wheel.
If you don't need to
install pulleys or gears, continue with step 2. |
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To mount a pulley
or gear next to one wheel, it is a good idea to cut
some space for that on your chassis; otherwise, one
wheel will stand out and your model will not have a
symmetrical shape. The size of this space may vary
depending on the size of your pulley or gear.
(3/8" x 1 1/2" cut
is shown in this example) |
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This is how a
pulley or gear may be mounted beside one of the
wheels. The pulley or gear must have a hole matching
the axle diameter and must feet snugly. Some pulleys
and gears require a plastic insert and some drilling
in order to adapt the diameter of the axle you are
using. |
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After
mounting, make sure that the wheels can spin freely.
If necessary, mount a metal washer between the
spacer and eye screws. |
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Other
methods of mounting the axle
You may not have
eye screws for mounting the axles. This is an
alternate method for mounting wheels and axle.
Insert the axle in one
wheel, slide a washer onto it. Insert a 5 1/2" straw
over it and finally insert another washer and
another wheel. |
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Your final wheels
and axle will look like this. Hold the straw and
spin the wheels. Make sure the wheels can spin
freely. If necessary, make some adjustments. |
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Cut 4 pieces of 2"
(5cm) long wood strips and glue them about 1/5"
(5mm) apart where you want to mount the axles. |
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Insert the axle in
the space between the strips and secure them in
place using some glue. Cover it with a strip of
cardboard or heavy construction paper. |
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Note that the glue
will touch the straw, not the axle. This is how the
bottom of your car will look like after covering the
axle holder with a strip of paper. |
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Alternate Assembly Procedure for gear driven
solar car
The following steps relate to the construction of the basic solar racer
vehicle. Steps relating to the completion of the propulsion systems are left to
the student's discretion.
- Make sure your kit contains the items listed.
- Locate the grid planning sheet in the kit.
- Using a pencil and ruler, design the body of the vehicle and propulsion
system.
Remember, the lighter the vehicle's body, the further it will travel.
- Show the drawing to the teacher when ready.
- Locate the balsawood sheet from the kit
- Transfer the vehicle body pattern to the balsawood.
- Using the craft knife and straight-edge,
carefully cut out the vehicle body.
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- Locate the straw from the kit. Also get scissors and glue
gun.
- Cut straw in half
- Using the glue gun, attach the straws to the bottom of
vehicle, one at each end (parallel to the end)
- Locate the axles through each straw.
- Push one wheel into each axle.
- Insert and axle through each straw.
- Carefully place the remaining wheel onto each axle.
Note: This completes construction of the basic solar vehicle.
- Locate the solar cell Panel and the required parts for the
propulsion system chosen gears, pulleys, propeller, or rubber
band. (Gears are supplied, Pulleys and propellers are optional.
- Assemble and attach the propulsion system as designed.
- Finish your solar racer as desired using paint, markers,
etc.
- Race the assembled vehicle on a flat surface in a sunny day.
If you don't have this
kit, you can order it now! It is available both as a single
pack and class pack. Kit content may be different from the
images shown in this page.

Secure
Online Store
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Test your car indoor:
You can test
your car indoor by replacing the sunlight with a strong portable
light (Contractor's work light) you may buy from a hardware store.
Just position the lamp about 2 feet above the car and see how it
works. For best results the portable lamp must have at least a 120
Watt bulb and a reflector.
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