3
4
3. Hang a short frame (3) on the four anchor pins on the other side as
well. The two short frames should be positioned exactly across from
each other at the same height.
4. Now attach a base plate (1) to the top. It should extend right up
to the short vertical frame at the front. On each side, the base plate
should be positioned over a row of holes.
Results
The parts that you have assembled have only a mod-
est weight to them. Simply converting the tractor to a
transport vehicle should not have changed its driving
performance yet.
Adding a Load
Now let’s find out how much weight your first solar
vehicle can handle. We can only determine how
strong your solar transporter is by loading weights
onto its cargo bed. The technical term is “payload.”
Experiment 21
>
You will need: light, solar transporter, level
ground, blocks or small stones as payload
Instructions
Collect a variety of things that you can use to load
your vehicle, such as wooden blocks or small rocks.
Start with light objects. Check to see if your solar
transporter can carry the load. Keep increasing the
weight. What happens?
Results
Your solar transporter can easily carry light objects.
The more weight you add to the platform, the harder
it is for the vehicle. When you load on too much
weight, the engine can’t carry the payload — your
vehicle stays put.
Maximum Payload
Of course, it would be interesting to know exactly
what the maximum payload is for your transport ve-
hicle. To determine that, you will need a kitchen scale.
Experiment 22
>
You will need: light, solar transporter, level
ground, blocks or small stones as payload, kitchen
scale
Instructions
Find out what the maximum weight is that your solar
car can carry and how much weight will overburden it.
To do that, weigh the payload with your kitchen scale
before loading it onto the cargo bed. Keep increasing
the weight of the load until the engine isn’t strong
enough to move the vehicle. Write down your find-
ings.
Results
Your model is pretty strong. In bright sunlight and on
an even surface, it can pull up to 500 grams (about 1
lb.) of weight.
Transporting a Load Uphill
When you were investigating the driving performance
of your tractor, you learned about the considerable
influence that inclines and declines can have. In the
next experiments, we will determine whether slopes
can also have an influence on payload.
Experiment 23
>
You will need: light, solar transporter, large draw-
ing pad, blocks or small rocks as payload
Instructions
Have your model drive up a slightly inclined plane.
Vary the payload and observe what happens.
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