dRuBbLe


Summary

Bounce a kick ball off the top of a bar stool, with views of Washington, D.C. in the background

Three game modes

• Single dRuBbLe - Bounce as far and high as possible
• Double dRuBbLe - Alternate bounces with a computer player
• Volley dRuBbLe - Don't let the ball stop on your side

Three difficulty settings

• Easy - Pace is slower, and stool is wider
• Hard - Pace and stool width are realistic
• Silly - Pace is silly fast, stool is silly skinny

How to play:

There are two virtual sticks which appear as crosshairs on the screen. Touch the stick on the left to move the stool. Touch the stick on the right to move the player. Use the action button in the upper right to start the game. Tap once to set the launch angle. Tap again to set the speed and launch the ball. The options button in the upper left will return to the game selection screen. Your goal is to bounce the ball off the top of your stool, as far and as high as possible.

There are three game modes, with a fourth planned:

Single dRuBbLe

Throw it up, bounce it on the stool, try to keep it bouncing. Your score is the product of your distance, max height, and number of bounces.

Double dRuBbLe

First person throws it, second person tries to bounce it as far as they can on the stool. The two players alternate shots.

Volley dRuBbLe

First person bounces it over the center barrier, second person attempts to return it. The round ends when the ball hits the ground, at which time the last player to hit the ball over the barrier earns a point.

Triple dRuBbLe (Planned)

First person throws it, second person bounces it to the third person, who bounces it to the first person who has run behind them.

The History of dRuBbLe

A game we used to play while drinking in college.

Dynamics Model

The player is modeled as a mass that is allowed to translate in the horizontal x and vertical y directions. A spring and damper attach the player to the ground in the y coordinate. The stool is modeled as a point mass that is first offset vertically from the player mass by a distance d, then radially from this offset point by an additional distance l, where the rotation of the offset relative to the vertical axis is given by the angle $\theta$. Given the description above, the dynamics are represented by a 4 degree-of-freedom 4-DOF system where the generalized coordinates are q = (x, y, l, $\theta$), which is visually represented in Figure 1.

Figure 1 - Dynamics Model Diagram