Gravity Vehicle C

[windu34]

Gravity Vehicle C: Teams design, build and test one Vehicle and Ramp that uses the Vehicle's gravitational potential energy as its sole means of propulsion to reach a target as quickly and accurately as possible.

Gravity Vehicle Wiki

Gravity Vehicle Image Gallery

Scioly.org Vehicle Events Presentation

Past Threads: 2012, 2013

[AngelMB]

Taking into account the new scoring methodology, I expect top scores to be significantly lower from the last time Gravity Vehicle was an event (high 200's I believe). If anything, they should be closer to the top scores that Mousetrap Vehicle had last year (Sub 20). Obviously we can't tell what times and accuracy vehicles will have right now, but I expect similar times to MV and an improvement to the accuracies we saw with MV as teams can slow down past the 8.5 meter mark to ensure less jumpiness and 'fish-tailing' that would occur from braking at high speeds.

[sciolyperson1]

Taking into account the new scoring methodology, I expect top scores to be significantly lower from the last time Gravity Vehicle was an event (high 200's I believe). If anything, they should be closer to the top scores that Mousetrap Vehicle had last year (Sub 20). Obviously we can't tell what times and accuracy vehicles will have right now, but I expect similar times to MV and an improvement to the accuracies we saw with MV as teams can slow down past the 8.5 meter mark to ensure less jumpiness and 'fish-tailing' that would occur from braking at high speeds.

Can you clarify what you mean by the slow down past the 8.5m mark?

[MTV<=>Operator]

Can you clarify what you mean by the slow down past the 8.5m mark?

Given that the time is now taken by two photogates (one at the .5 meter mark and one at the 8.5 meter mark), teams can now adapt their vehicles to brake over a distance of half a meter because the shortest distance it will have to stop at is 9 meters. This 0.5 meter buffer distance would allow for a system (such as a wingnut with a spring) that would cause the vehicle to slow down before coming to a stop and would effectively reduce or eliminate skidding.

[AngelMB]

Can you clarify what you mean by the slow down past the 8.5m mark?

Given that the time is now taken by two photogates (one at the .5 meter mark and one at the 8.5 meter mark), teams can now adapt their vehicles to brake over a distance of half a meter because the shortest distance it will have to stop at is 9 meters. This 0.5 meter buffer distance would allow for a system (such as a wingnut with a spring) that would cause the vehicle to slow down before coming to a stop and would effectively reduce or eliminate skidding.

Precisely, I also believe the accuracy scores should be at least slightly better since the track once again follows a straight line rather than a curve like last year.

[windu34]

Given that the time is now taken by two photogates (one at the .5 meter mark and one at the 8.5 meter mark), teams can now adapt their vehicles to brake over a distance of half a meter because the shortest distance it will have to stop at is 9 meters. This 0.5 meter buffer distance would allow for a system (such as a wingnut with a spring) that would cause the vehicle to slow down before coming to a stop and would effectively reduce or eliminate skidding.

One thing to watch out for is making sure your vehicle still has enough momentum to reach the target point, a mistake I made doing EV back in the day.

[chessbucket]

Is it just me or is striving to make a brachistochrone curve or optimize time to reach the bottom of the ramp a useless consideration now that the timings start after the vehicle has left the ramp? Even if timing started when the vehicle was released, I doubt having a brachistochrone ramp curve would make a difference. IIRC, you would have to have the center of mass of the vehicle travel in the brachistochrone trajectory which is a pain. I predict 1-6 at nationals to be sub 10

[Unome]

Is it just me or is striving to make a brachistochrone curve or optimize time to reach the bottom of the ramp a useless consideration now that the timings start after the vehicle has left the ramp? Even if timing started when the vehicle was released, I doubt having a brachistochrone ramp curve would make a difference. IIRC, you would have to have the center of mass of the vehicle travel in the brachistochrone trajectory which is a pain. I predict 1-6 at nationals to be sub 10

You're right, from what I've heard. This was mentioned at SOSI.

[someone1580]

Where do you guys buy these specialized ramps? Also, what design do you recommend besides the Brachistichrone Curve?

[Unome]

Where do you guys buy these specialized ramps?

Generally you build them.