3. Testing and Modification

3.1 Trial Test and Design Modification

Run Number

Run 1
Run 2
Run 3
Total Time of Run

0
05:48
05:03
Total Distance

0m          
5.4m
5.4m
Time for Lever to fully release

 NIL
05:48
05:03
Distance Car Travel while lever is releasing
0m

5.3m
5.3m
Observation
The car did not move.
Car travelled a little faster but still not very fast
Car travelled a little faster but can be further improved

Lever Operation
The lever did not move


Snapped but lesser
Did not snap
File Name for Video
Area for Improvement
The rod that we used was a square rod.
The string was not long enough
The wheels had a lot of friction
Possible reason
This is because, the square rod has edges. Hence, when the string is pulled to be uncoiled and move the wheels, the flat edges of the square rod is pulled and pressed against surface of the axle whole, hence preventing the axle from turning.

Due to the length of the string being too short, the force applied by the mousetrap was not maximised, causing the wheel to spin for a lesser time which decreases total distance travelled. 
The friction between the axle and the axle holders were too high
Modification Made
We changed the square rod into a circular one. 
We increased the length of the string used. 
We greased the axle holes.

MODIFICATION (New Google-sketchup)






3.2 Test Data

1. All relevant measurements of car (after modification).
Mass of your car
200g
Mass of each wheel (or one of they are all the same)
15.0g
Wheel diameter
11.8cm
Axle diameter
0.60cm
Length of string (power stroke)
33.0cm
Approx. number of wraps of string
7.00
Length of lever extension
11.0cm
Overall length
33.0cm
Overall width
11.8cm
Overall height
15.3cm

2. Data tables showing the results of all 3 trials.

Run Number

Run 1
Run 2
Run 3
Total Time of Run

09:03
08:61
10:33
Total Distance

5.55m
5.78m
5.48m
Time for Lever to fully release

08:46
07:67
09:55
Distance Car Travel while lever is releasing
5.45m




5.68m
5.38m
Observation
The mousetrap gradually released. 
The mousetrap gradually released. 
The mousetrap gradually released.

Lever Operation
The lever released in a smooth fashion
The lever released in a relatively smooth fashion
The lever released very smoothly
File Name for Video


Competition Rules

Student teams will design and build their own vehicle which must be solely powered by a standard mousetrap. Competition rules are as follows:

1. The standard mousetrap must be mounted to the chassis and must not be painted or decorated

2. The springs on the mousetrap may not be cut, bent, over- wound, heat-treated or altered in any other manner. No additional source of elastic potential energy can be incorporated into the engine/drivetrain mechanism.

3. Additional inputs of energy are not allowed as part of the official competition.

4. Teams may supply some of their own materials and are encouraged to use recycled, re-purposed materials. Kits are not allowed.

5. Distance traveled will be measured from the front axle to the point where the front axle stops or leaves the designated track area. Distance will be measured as a straight line path.

6. Vehicles must have 3 or 4 wheels. All wheel materials and designs are permitted.

7. Students are permitted to design the chassis of their choice.

8. Engineering modifications such as gearing, lubricants, bushings and bearings are permitted.

9. Testing will consist of three runs and the best score will count. MTV design cannot be altered between these runs. Minor adjustments are permitted with the instructor’s permission and must be documented.



SCORING

Teams must decide to focus on distance, acceleration or an optimized combination of both.

Scoring for the actual construction and testing of the mousetrap will be as follows:



Total Score = 100 – 10p + 2d – 2t

Base score 100 pts

Number of rule violations p (min: 0 pts)

Each 0.5 meters travelled (up to 8 meters) d (max: 16 pts)

Seconds travelled (at least 1 second) t (min: 1 pts)




A score of 130 is considered 100% for this part of the project.
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