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Fzxrlz wrote:While rule changes to the hovercraft provide a good platform for development, I am disappointed in the track changes. As a coach & hovercraft event supervisor, I built 4 tracks for B & C Regionals last year. They are useless this year. Even the photogates cannot be reworked with the meandering of the craft. Only Vernier photogates can be adapted which we don't have. I tried to order them, but Vernier only accepts "requests for quotes", not orders. They say they will respond, but haven't.

I agree that using photogates is somewhat tough for Hovercraft, especially since devices are so prone to rotating/getting stuck along the track this year. Personally, I think that using multiple (~3) manual timers is good enough when other aspects of the event (a quality test, mass score, chart score, etc) should be able to make up for any slight differences in time.

Fzxrlz wrote:The C division tracks have to be 10 to 11 feet to accommodate the variance that can be specified. You can't get materials that long. This means a two piece track (also required to transport it). Now the connection and seam needs to be perfectly sealed and smooth.

Using a gym floor with steel 2x4s does not work in the gyms due to the risk of marring the floor. The website still shows the pre 2017 configuration. Any suggestions?

I think it's possible to get by with a bit less than the maximum. The maximum timed length for Division C is 260 cm, which amounts to a total length of around 310cm (about 5cm over 10 feet). However, rule 5(a) says that the track only has to be at least 215 centimeters (which would be the shortest possible track using a distance of 165 cm). If you use metal studs like these, which are 10 feet (304.8 cm) long, you'd be able to cover nearly every possible length for Division C (94.8%) without needing multiple pieces for the track and still fit the rules.

Fzxrlz wrote:While rule changes to the hovercraft provide a good platform for development, I am disappointed in the track changes. As a coach & hovercraft event supervisor, I built 4 tracks for B & C Regionals last year. They are useless this year. Even the photogates cannot be reworked with the meandering of the craft. Only Vernier photogates can be adapted which we don't have. I tried to order them, but Vernier only accepts "requests for quotes", not orders. They say they will respond, but haven't. The C division tracks have to be 10 to 11 feet to accommodate the variance that can be specified. You can't get materials that long. This means a two piece track (also required to transport it). Now the connection and seam needs to be perfectly sealed and smooth.

Using a gym floor with steel 2x4s does not work in the gyms due to the risk of marring the floor. The website still shows the pre 2017 configuration. Any suggestions?

A couple comments:

-We deliberately designed the track dimensions to permit the use of tracks from last year with minor modifications for a portion of the potential range. To be clear, you should be able to make some minor modifications to your 4 tracks to make them work in certain situations this year (you won't be able to have the max track length obviously).
-You can get Vernier photogates from Ward's Sci, which is an official sponsor of SO (and you can get a discount code in the rules manual): https://wardsci.com/store/product/88918 ... -photogate
-I recommend using wooden 2x4s. Those won't mar a gym floor and should work well. I hope to get a document illustrating how to build one that is essentially a oversized picture frame you just lay down on the floor.

chalker wrote:

Fzxrlz wrote:We deliberately designed the track dimensions to permit the use of tracks from last year with minor modifications for a portion of the potential range. .

If that was your intent, I can't say that you hit it. My test track from last year was mounted to a 2' x 8' piece of plywood I had kicking around. It fails on both length and width for this year.

As an irresponsible, frequently forgetful person, I lost my Hovercraft rules sheet :/ So does anybody know the width and length of the track this year for Division C?

geniusjohn5 wrote:As an irresponsible, frequently forgetful person, I lost my Hovercraft rules sheet :/ So does anybody know the width and length of the track this year for Division C?

Width is 60 cm and length is between 165 and 260 cm depending on what the proctor chooses. Time is always the same (15 seconds)

geniusjohn5 wrote:As an irresponsible, frequently forgetful person, I lost my Hovercraft rules sheet :/ So does anybody know the width and length of the track this year for Division C?

You can get the rules off of soinc.org here

chalker wrote:

Fzxrlz wrote:While rule changes to the hovercraft provide a good platform for development, I am disappointed in the track changes. As a coach & hovercraft event supervisor, I built 4 tracks for B & C Regionals last year. They are useless this year. Even the photogates cannot be reworked with the meandering of the craft. Only Vernier photogates can be adapted which we don't have. I tried to order them, but Vernier only accepts "requests for quotes", not orders. They say they will respond, but haven't. The C division tracks have to be 10 to 11 feet to accommodate the variance that can be specified. You can't get materials that long. This means a two piece track (also required to transport it). Now the connection and seam needs to be perfectly sealed and smooth.

Using a gym floor with steel 2x4s does not work in the gyms due to the risk of marring the floor. The website still shows the pre 2017 configuration. Any suggestions?

A couple comments:

-We deliberately designed the track dimensions to permit the use of tracks from last year with minor modifications for a portion of the potential range. To be clear, you should be able to make some minor modifications to your 4 tracks to make them work in certain situations this year (you won't be able to have the max track length obviously).
-You can get Vernier photogates from Ward's Sci, which is an official sponsor of SO (and you can get a discount code in the rules manual): https://wardsci.com/store/product/88918 ... -photogate
-I recommend using wooden 2x4s. Those won't mar a gym floor and should work well. I hope to get a document illustrating how to build one that is essentially a oversized picture frame you just lay down on the floor.

Thank you! This is helpful. I think I will try the picture frame idea.

Does anybody have any ideas on how to set up a good track to test a Hovercraft at home? It's Christmas break and I can't go to the school to test out my hovercraft.

geniusjohn5 wrote:Does anybody have any ideas on how to set up a good track to test a Hovercraft at home? It's Christmas break and I can't go to the school to test out my hovercraft.

On Tuesday, if you have a room with a vinyl tile or linoleum floor, go to Home Depot (or other) and get 2 wood or steel 2x4's. Lay them out on the floor. Maybe weigh them down by setting chair legs on them.

2x4's should cost about $3-$6 each

Can someone clarify what the graphs are supposed to be? The rules say they have to show the relationship between "distance and time." Does that mean that the 2 variables in the graph are distance and time, or can we have other variables like resistance and time for a constant distance? Also, what does it mean by having data span one variable range?