The Hall of Science is blessed with an outdoor, science-themed playground on which there are two large, two-story slides. We felt this was the perfect place to have visitors play a game around the concepts of potential and kinetic energy, energy lost due to friction (PE, KE and E-lost, respectively) and the conversion of energy between those states.
By outfitting one of the slides with sensors to measure position and time and placing a scale at the top to collect students' weight, enough data could be collected in any run to yield a wealth of information about energy and friction. However, the challenge was to hand pick which of this data to present to visitors so as not to inundate them with facts and figures and to format it into an easy to understand but compelling and fun interface.
Through several design iterations, we arrived at a game that gives students several different mats to slide on in order to tweak their final values of KE and E-lost to place a virtual version of themselves onto a target dependent on these same values.
The sequence of images below show the user interface through some of its stages of animation. After a student has weighed themselves on the scale, a target appropriate for their weight is set. Once they descend and the sensors have logged their velocity data the information is sent to their digital counterpart. Their avatar falls down the slide and lands in a hot air balloon equipped with a propeller. Their E-lost, also known as heat, causes the hot air balloon to ascend the Y-axis while their KE causes the propeller to spin, pushing it along the X-axis towards their target. All the while, a piechart showing the distribution of their different types of energy is animated to move and flashes during the relevant portions of the character's movement.
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| Student's character begins descent down the slide. Energy begins conversion from PE (blue) to KE (green) and energy lost to friction (red). |
Note: A piechart was chosen as the visualization of choice as it reflects the conservation of total energy even though the energy may be in different forms from start to finish. Also, the size of the piechart reflects the total energy of the user, meaning a heavier user will have more potential energy and hence a larger piechart.
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| Halfway down, energy continues conversion from PE to KE and E-lost |
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| User lands in hot air balloon basket and the next portion of the story begins: using the different types of energy to move towards the target. |
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| The red E-lost portion of the piechart is depleted while causing the balloon to rise up the y-axis. The balloon glows red to reinforce the connection between the motion of the balloon and E-lost. |
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| After reaching the maximum height possible with a given user's E-lost, the propeller glows green as the user's KE causes the balloon to move along the x-axis. |
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| If all goes well and the student has chosen altered their friction wisely, they achieve the right combination of KE and E-lost and land on their target. |
