ENGR 102 – Spring 2001, Section 5,        Dr. D. Birnie

Catapult Competition Results – Round 1

 

 

Team

Xcen

Ycen

Nhits

PI

Xscat

Yscat

Score

1

10.05

4.00

8

2092.5

9.3

5.6

17.7

2

-0.55

-6.10

7

1692.0

12.7

6.3

19.7

3

4.00

5.65

8

2139.25

10.1

9.9

17.5

4

4.50

4.85

9

1987.0

13.0

2.1

18.2

5

-12.25

0.85

2

3281.5

13.4

7.4

14.2

6

-3.80

2.75

8

1878.5

12.8

5.0

18.7

7

1.00

-6.90

2

3460.25

18.6

6.7

13.8

8

2.85

1.15

10

731.5

5.5

6.3

30.0

 

Notes on Variables:

 

X is measured from the red dot: positive is away from catapult, negative is nearer to the catapult.

 

Y is measured from the red dot: positive is to the right and negative is to the left.

 

(Xcen,Ycen) is the average of the hit locations and represents the place where it would have been best to be aiming at.

 

(Xscat,Yscat) is the standard deviation of the hit coordinates in the distance and left/right directions.

 

PI is the sum of the square of the distances from the hit locations to the red dot, but with the limitation that no individual hit distance is allowed to be larger than 20 cm. This determines that the MAXIMUM PI can be is 4000. The minimum is zero if all shots were direct hits.

 

Nhits is then the number of hits that fell within that radius of 20 cm.  So some shots that fell on the paper, but near the corners, could have been beyond the 20 cm distance.

 

“Score” is the number of points awarded to each team – is out of 30 possible points. Is determined by 30*sqrt((best PI)/(your PI)). I added the square root since the linear formula scaled as (the standard deviation squared) rather than just the standard deviation as I had intended.