December 6, 2007
EF 151 D-2
THE CHUCK MOBILE
By
Daniel Knecht
Stewart Goodwin
Andrew Bohon
Kyle Kuderewski
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THE CHUCK MOBILE
Overview
The objective of this project was to create a complex motor which would lift a
1kg weight the height of 1 meter in 10 seconds. Through the careful analysis of energy
conservation we achieved a fully functional design which preformed this task with little
to no effort. The constructions were simple yet highly elaborate in their conception.
Utilizing gravitational potential energy through an elevated ramp, elastic potential energy
built up in the spring of the mousetrap, and electric potential energy (formally, work in),
generated by volts per time unit in the mechanical blender. At our best we achieved a 1
meter ascent in 8 seconds.
Design Process
In the initial phases of design, we sat down to discuss possible solutions for the
project. The first brain-stormed ideas consisted of a rat design, a water pulley system, and
an advanced aeronautical machine—not the most cost-efficient of propositions.
The rat system was by far the most creative, comprising of living organisms that
think and feel just as we humans do. The rats would perform the super-rodent feats of
pulling a giant 1kg mass up 1 meter by forcing their tiny hands against the ground,
demonstrating Newton’s 3rd law of motion. By dangling a smelly piece of cheese directly
over their heads, we would motivate several joules of energy to flow freely into our
calculations and out of their little bodies thus achieving the most unique design every
attempted in the history of UT engineering… This idea brought too many challenges to
the table so we chucked it out for the chuck mobile.
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In the chuck mobile design, we set a bucket of water on top of a plank of wood
with wheels and let gravity steer the mini-buggy down the ramp. Set atop an incline plane,
we could use potential energy from the car’s elevation to pull the counter-weight 1 meter
upwards. I sat down excited by this idea and anxiously began my calculations. In a mater
of minutes I had the whole thing figured out. However, we were in for a devastating
failure. The amount of weight required to pull the counter weight up exceeded 8 kg with
the incline. I suggested tilting the ramp further but then we would have exceeded our
height limit. All of our alternatives had been exhausted, so collectively; we were forced
to start over.
Our final successful design centered on the idea of an electric current set off by a
mouse trap. How we would set this up remained a problem. Andrew Bohon did not
believe that this would be possible to do, so I proved him wrong. After 6 hours of circuit
construction and circuit testing I completed a consistent and operational electric current
through a blender with the mouse trap acting as a power switch. A ball would roll down a
z-shaped ramp, hit the mouse trap, close the circuit, and power the blender which would
cut a string and release a counter-weight to complete the objective.
Construction (product)
There were many steps in piecing together the blender, wood, and metal ramp.
Apart from drilling and taping all the joints of the structure, the circuit construction
process took the longest and is the main focus of our design. The idea of using an electric
current was very logical and original. The first step was to change the wire arrangement. I
removed the higher speeds from the control so that we would avoid any unnecessary
accidents and then I essentially elongated the principle connection with a gap between the
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direct current functioning as a switch; whenever a conductor is placed in conjunction of
the two open wires, the current flows and operates the blender.
M ball gh  M weight gh 
1 2
kx  600 joules  PE   KE   Eloss
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Stored Energy in device
The energy in the device is mostly potential and electrical. In the middle, some elastic
potential energy is stored in a mouse trap, but it’s mostly wasted.
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The ball starts out with potential energy of .3476N
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Which sets off the mouse trap releasing stored energy, but more importantly
closes a circuit
•
The closed circuit starts the energy flow of the mixer which is 120V
•
The blade cuts the string releasing the stored energy in our weight which has a
force of (9.81+.125)N
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Materials and Expenditures
One of the most important parts for the construction of the project was finding
resources and materials to build our device. One mistake we made was to not first look
for materials already available to us. Instead, going on our first design plan, we went to
Ace Hardware and purchased several large pieces of wood that nearly went over our
budget of $20. We should have first planned out our design to make sure it would work
before we dropped all of our money on wood and supplies. We were very relieved to
find many resources available to us in Estabrook 13. With our first design concept of the
car holding water rolling down the ramp, we found a small coffee pot that would work
well to hold the water. We also even found some wheels to be used for the car rolling
down the ramp.
Unfortunately, our design of the car holding water proved to be a failure because the
weight of the car would have to be over 2.5 kg which would violate the rules outlined in
the guidelines. We were then forced to change our design to the Chuck Mobile, which
involved a ball rolling down a ramp, a mousetrap, an egg-beater with an attached razor,
and a string releasing a counter-weight. The problem with our new design meant we
needed new materials, but we didn’t want to go over our budget so we were forced to use
the materials we already had, or any other things we could find. The egg-beater we found
was a major help and probably the greatest aspect of our design. It was also a relief
knowing that mousetraps were provided. In the end we only went over our budget by a
little because of the change in design. Below is a list and bill of our materials:
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Materials
Cost
2 x 4 ft piece of plywood
$11.73
½ x 10 ft piece of wood
$5.09
Egg-beater (blender)
$3.44 (goodwill)
mousetrap
$0.50
String
$0.50
Razor
$0.50
Metal hook
$0.25
Scraps of metal for ramp
$0.25
Screw/nails
$0.10
Total cost
$22.36
Conclusion
Although we had our ups and downs and our device failed to operate effectively
during presentation it was an overall success. Everyone who saw our design loved its
creativity, and originality. However, getting these results was not easy and came with a
struggle. We learned that working together as a team is probably the most crucial part of
any engineering project. It was hard for us at first because everyone believed in their
own idea, and no one wanted to agree on anything. We finally came together with a
compromise and established our winning idea. We also learned how beneficial it is to
plan out an idea ahead of time before buying materials and getting too far into it. We
should have established a plan, divided the work among our group, and worked together.
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This would have made the project a lot more cost and time effective. In the end our
problems were resolved and we produced a successful motor.
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