Testing and Modifications The Catapult Project – Caroline Gordon 1

Collecting Data Once our catapult was completed, we tested it outside using targets drawn and painted on posted paper. These were at 5, 10, and 15 meter distances. The group collected 60 data points at each distance, for a total of 180 data collections. Our data and success rates at each distance are shown in the next slides. 2

Key In all of our testing, we used the same scoring method for each area of the target. The colored area of the target goes (from the innermost ring to the outside): Red, yellow, blue, white, and not on target. Red Area – 4 points Yellow Area – 3 points Blue Area – 2 points White Area – 1 point Not on Target (Grass) – 0 points 3

Target 4

5 Meter Data Collection Trial NumberPoints/Colored AreaTrial NumberPoints/Colored Area 13/ Yellow310/ Grass 2 322/ Blue 30/ Grass330/ Grass 4 340/ Grass 5 352/ Blue 61/ White361/ White 7 373/ Yellow 8 380/ Grass 9 390/ Grass 102/ Blue400/ Grass 110/ Grass410/ Grass 121/ White423/ Yellow 133/ Yellow430/ Grass 144/ Red442/ Blue 150/ Grass452/ Blue 160/ Grass462/ Blue 170/ Grass470/ Grass 182/ Blue482/ Blue 190/ Grass494/ Red 200/Grass500/ Grass 211/ White510/ Grass 222/ Blue524/ Red 230/ Grass531/ White 240/ Grass540/ Grass 250/ Grass551/ White 262/ Blue560/ Grass 270/ Grass 57 0/ Grass 280/ Grass580/ Grass 291/ White593/ Yellow 301/ White601/ White 5

10 Meter Data Collection Trial NumberPoints/Colored AreaTrial NumberPoints/Colored Area 1 0/ Grass31 0/ Grass / Red 3 1/ White33 0/ Grass 4 1/ White34 0/ Grass 5 2/ Blue35 0/ Grass 6 3/ Yellow36 0/ Grass 7 2/ Blue37 0/ Grass 8 1/ White38 2/ Blue 9 0/ Grass39 0/ Grass 10 0/ Grass40 4/ Red 11 2/ Blue41 0/ Grass 12 0/ Grass42 2/ Blue 13 3/ Yellow43 0/ Grass 14 2/ Blue44 2/ Blue 15 0/ Grass45 2/ Blue 16 0/ Grass46 1/ White 17 1/ White47 0/ Grass 18 0/ Grass48 0/ Grass 19 0/ Grass49 2/ Blue 20 0/ Grass50 0/ Grass 21 2/ Blue51 0/ Grass 22 0/ Grass52 0/ Grass 23 0/ Grass53 0/ Grass 24 2/ Blue54 4/ Red 25 4/ Red55 0/ Grass 26 1/ White56 0/ Grass 27 0/ Grass 57 1/ White 28 0/ Grass58 0/ Grass 29 1/ White59 0/ Grass 30 0/ Grass60 0/Grass 6

15 Meter Data Collection Trial NumberPoints/Colored AreaTrial NumberPoints/Colored Area 1 0/ Grass31 4/ Red 2 2/ Blue32 3/ Yellow 3 0/ Grass33 0/ Grass / Grass / Grass / Grass / White 8 0 / Grass 38 2/ Blue 9 0/ Grass39 1/ White 10 0/ Grass40 0/ Grass 11 0/ Grass41 0/ Grass 12 0/ Grass42 0/ Grass 13 0/ Grass43 2/ Blue 14 0/ Grass44 0/ Grass 15 0/ Grass45 0/ Grass 16 0/ Grass46 0/ Grass 17 0/ Grass47 0/ Grass 18 0/ Grass48 0/ Grass 19 0/ Grass49 2/ Blue 20 1/ White50 0/ Grass 21 0/ Grass51 0/ Grass 22 0/ Grass52 0/ Grass 23 0/ Grass53 2/ Blue 24 0/ Grass54 1/ White 25 0/ Grass55 0/ Grass 26 1/ White56 0/ Grass 27 0/ Grass 57 2/ Blue 28 2/ Blue58 0/ Grass 29 1/ White59 0/ Grass 30 1/ White60 1/ White 7

Success Rate Calculations To calculate the success rates of the catapult at different colored areas, a table was constructed for each distance. The first column of information is how many points were earned at each colored section. The second column includes how many times that area was hit throughout the trials. The third column shows the probability/success rate of the projectile landing on that colored section.  This probability was calculated by dividing the number of times the projectile hit the area by 60, the total number of trials.  This decimal was then converted into a percentage and rounded to the nearest whole number. 8

5 Meter Success Rate Points/ Colored Area Total points earned Total times out of 60 projectile hit colored area Success rate as percentage *rounded* Red (4 pts) % Yellow (3 pts) % Blue (2 pts) % White (1 pt) 10 17% Not on Target (0 pts) % Total60 out of Possible out of Total 60 9

10 Meter Success Rate Points/ Colored Area Total points earned Total times out of 60 projectile hit colored area Success rate as percentage *rounded* Red (4 pts) % Yellow (3 pts) 5 2 3% Blue (2 pts) % White (1 pt) % Not on Target (0 pts) % Total51 out of Possible out of Total 60 10

15 Meter Success Rate Points/ Colored Area Total points earned Total times out of 60 projectile hit colored area Success rate as percentage *rounded* Red (4 pts) 4 1 2% Yellow (3 pts) 3 1 2% Blue (2 pts) % White (1 pt) % Not on Target (0 pts) % Total 29 out of Possible out of Total 60 11

Redesign After we collected the first round of data and calculated the success rates of the catapult, the group felt like a few changes needed to be made. One of these changes was adjusting the length of the lever. Although the catapult could reach the 15 meter distance, it did not go very high in the air and had more of a line-drive motion. The group felt that if the projectiles could go farther into the air, it would be easier to land on the targets. Another change was pulling the string at the bottom of the catapult tighter to reduce the slack and create more tension and a strong support system for the lever. 12

Finished Catapult – Round 2 13