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The team will design, construct, calibrate, and shoot a device capable of launching a ball into a target area, and collect data to develop a series of graphs relating launch configuration to target distance and height.

Prior to competition, students are to develop and use performance data and calibrations charts to assist in determining the best launch parameters given different distances and heights.

Sample graphs at www.soinc.org

Launch devices,copies ofgraphs,and all materials the team will use (other than Protective Goggles),are to be impounded.

Target distances and heights will not be announced until all devices have been impounded.

High Impact Particle Protection Gogglesmust be worn during building, testing and launching.See www.soinc.org/general /protection

Impact Protection

Another attribute to be considered is Impact Protection. Protective eyewear bearing the mark "Z87" provides basic impact protection. Devices that meet the "High Impact" specifications of ANSI Z87.1-2003 are identified by the mark "Z87+".

High Impact protection is indicated when there may be a high inertia particle hazard (high mass or velocity). This will be specified in the rules by preceding the type of protective eyewear above with the words "High Impact". e.g. High Impact Particle Protection Goggles

Event supervisors may disqualify any apparatus that is operated in an unsafe manner.

Launching force must be supplied by non-metallic elastic solids such as rubber bands, bungie cords, rubber tubing, etc.

Must be triggered from outside of the launching area.Radio controlled triggering devices are not permitted but battery triggered devices are allowed.

Must fit within a 80 cm cubeprior to the first launch.

The triggering device(which is not considered part of the device)may extend out of the launch area and does not need to return to the launch area after launch.

Teams must make provisions to trigger the device if there is limited space behind the launch area (50 cm minimum).

Teams will provide a projectile that shall beany unmodified tennis ball, racquet ball, ping pong ball, or Hackie Sack (labeling is permitted.)

Students are not required to use the same projectile for every launch.

When instructed, students will place the device in a launch box 1 meter wide(perpendicular to the launch direction)and 1.5 m long,(designated by tape on the floor.)

Once teams are in the event area, they may not leave or receive outside assistance, materials, or communications.(General Rules) DQ

Students may not touch or hold the device, or be in the launch area,or in the area in front of the line that marks the front edge of the launch areaduring a shot.

Students may use weights to hold device in place but such weights must fit within the 80 cm cube.

Before and after a shot, all parts of the device must be within thelaunch area .

If any part of the device extends outside of thelaunch areaduring a launch, it must return to and remain in the launch area without assistance of the participants.

Two target areas will be placed in a straight line in front of the launch area , placed along a line which bisects the launch area .

Each target will be an approx. 1 meter square box or a 1 meter diameter circle.

Each will contain sand or cat litter approx. 1 cm deep to mark the impact area.

The center of the target areas will be marked so that the distance between the center of the initial projectile impact location and the center of the target may be measured.

The center of the target areas will be placed between 2 and 8 metersfor Division B and 2 and 10 meters for Division Cfrom the front of the launching area in 1 m intervals for Regional, m intervals for State, and 10 cm intervals for National)

The centers of the two targets must be separated by at least 2 meters.

The target areas will be at two different levels with the higher target being nearer to the launch area.

The higher target will bemeasuredin 10 cm intervals off the floor, up to one meterfor Division B and up to two meters for Division C.

The far target shall be at floor level.

Height of the target shall be measured from the floor to the top of the deep impact area.

Each team will have 10 minutesat Regionals and States, 8 minutes at Nationalsto place the launching device in the launch area, check the launch distances, and complete 4 shots.

Only2 shots made be made into each of the target areas.

Measurement time not included in allotted minutes.

No practice shots will be allowed but adjustments may be made to the launching device between shots.

Teams must inform the Event Supervisorbefore eachlaunch and as to which target they will be aiming.

When permitted by event supervisor, students may approach target after launch to make measurements to calibrate their device.

Students must not touch the target.

Student is warned for not properly wearing the safety goggles

A participant is in the launch orin front of the line that marks the front edge of the launch areawhen a launch occurs

No warning given prior to a launch.(Such launch, even if unintended, shall count as one of the four allowed launches.)

Any part of device is outside of 1m x 1.5 m launch areaprior to or after a launch .

Each team starts with 400 graph points which can be reduced by turning in graphs, notes, and other data at impound.

Each of 4selectedgraphs may reduce the Graph Score by 100 points.

Any number of graphs may be impounded but students must indicate which 4 should be used to determine the Graph Score.

Failure to indicate which graphs to score willresult in the 1 stfour graphs being scored .

Graphs and tables may be computer generated or hand drawn but must be on separate sheets of paper.

If drawn by hand, they must be drawn on graph paper.

Data tables mustbe on the same sheet of paper as the corresponding graph.

Graphs and tables must be properly labeled.

All variables and units must be identified.

Eachsheet of papermust be identified with the team name.

Start with 100 points per graph, 4 graphs total.

20 point reduction for completed data table

20 point reduction for graph

20 point reduction if graph matches data table

40 point reduction for graph being properly labeled (title, x & y variables, increments with units, team name)

Partial credit may be given

The winner will be the team with thelowestFinal Score.

Final Score = lower Close Target Area Score + lower Far Target Area Score + Graph Score + Penalties (if any)

It shall be the distance in mm from the center of the initial projectile impact location to the center of the target area.

Teams who miss the target area will score800mm for that shot.

It shall be measured similarly for a hit in the target area but measured to the impact location if outside the target area.

Supervisor(s) will visually note and mark the observed impact location outside the target area, then measure the distance in mm.

If the device fails to launch due to breakdown or other reason, Score for launch will be the distance from the front of the launch area to the center of the far target in mm.

If the announced target area is the far target but the projectile hits the nearer target, the score will be a straight line measured distance between the impact location and the center of the far target.

Lower Close Target Area Score = 10 mm

Lower Far Target Area Score = 1487 mm

Graph Score = 150

Penalties = 100

Final Score = 10 + 1487 + 150 + 100 = 1747

1 stTier Teams whose devices meet all specifications will be ranked by score.

2 ndTier Teams whose devices do not meet specifications listed in 3.a, 3.b, 3.c, and/or 3.d will be ranked by score.

1 stlower total of the sum of the two scored shots(to reward consistency)

2 ndclosest shotto center of target area

3 rd non-scored shot at the far target

4 th non-scored shot at the near target

Launch arm having several holes will allow students to determine the proper ratio of effort force to launch force.

Upright having several holes will allow students to experiment with launch arm height.

Upright being able to move it on the base will allow for experimentation.

Trigger something simple, free from jamming, and operates without the need to jerk anything too hard.

Non-metallic elastic material rubber bands?Bungie cords?The material they use to restrict the flow of blood for a blood draw?Plenty of room for experimentation.

Stopper having a series of holes will allow students to determine the proper height for the launch arm to stop moving.

Length of throwing arm.

Distance throwing arm drawn down or back.

It is up to thestudentsto design, construct, test, and calibrate the device.

Dennis Papesh

[email_address]

Mike McKee

[email_address]

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Education