Looking for cargo ball data

In the game manual, the cargo balls are noted to not hold a high tolerance. There have also been reports of some balls inflating to different sizes, and so far, there is no word on what PSI to expect the balls to be inflated to, just that they should be around 13 inches.

Today, we ran a few quick tests to try to characterize the “squishyness” of the cargo ball we received in the KOP, and are wondering if other teams are willing to perform similar tests with their KOP cargo balls and share their data to help the community understand the true variance of cargo balls. Here is our procedure:

  1. Inflate the ball to 13 inches. We didn’t have a method of checking the PSI of the ball in house, but if you can, that is meaningful data.
  2. Place the cargo ball on a scale and tare it
  3. Apply about 5 lbs of force (check force by looking at the scale reading) and measure the effective diameter. We applied force by pushing down on the ball with a sheet of plywood and measured the height of the plywood from the top of the scale.
  4. Repeat with 10 lbs of force, 15 lbs of force, and 20 lbs of force.

Here is the data we collected:
5.1 lbs: 12.75 in. diameter
10.6 lbs: 12.25 in. diameter
15.6 lbs: 12 in. diameter
20.2 lbs: 11.5 in. diameter

We would greatly appreciate as much data as we can get! Thank you!

2 Likes

It is likely, as in past years when using an inflatable ball, FIRST will use a “fork” or “box” to size the balls as they are inflated to the nominal 13". FIRST has always ignored the pressures of inflated game balls.