Hovercraft B/C

[Tesel]

That isn't my point. I am asking if a part of that type (electrical solenoids) are classified as motors.

Unfortunately, the only answer you're probably going to get is that it's iffy and comes down to opinion. In my opinion, it would count; in your ES's opinion, it might not.

The question it comes down to is this: Is it really that much better than a traditional motor, or should you stick with something more safe?

Thanks for responding. I designed a new system just now which uses traditional motors (simply is just a little more confusing to think about and implement).

Yeah, that makes perfect sense - sorry I couldn't be much help but clarifications like those are notoriously inconsistent. I hope it works out for your device!

[CMS AC]

Also, how close are people getting to the 15 second times? We're getting 10 on average, and nothing more than 13.

On our track at home, we've gotten 14-16 second times. However, it's a pretty rough track (concrete). At our latest competition, we got 12.5 seconds on smoother tile, although I don't remember the length. I assume that since the track length is constant for Div B, a lot of teams are getting fairly close to 15 seconds.

Oof...` How do you deal with inconsistencies in tracks? It's impossible to tell which side of the the track is higher, or what friction coefficient the track is going to be. Yet, teams still get consistent 15 second times...

[MattChina]

Also, how close are people getting to the 15 second times? We're getting 10 on average, and nothing more than 13.

On our track at home, we've gotten 14-16 second times. However, it's a pretty rough track (concrete). At our latest competition, we got 12.5 seconds on smoother tile, although I don't remember the length. I assume that since the track length is constant for Div B, a lot of teams are getting fairly close to 15 seconds.

Oof...` How do you deal with inconsistencies in tracks? It's impossible to tell which side of the the track is higher, or what friction coefficient the track is going to be. Yet, teams still get consistent 15 second times...

You get 5 tries. At least, that's what I tried to do. I don't know how to get 15 exactly every time. I guess people just test it on many different surfaces.

[sjhover]

Any tips on making the hovercraft go straight instead of turning sideways or spinning? Wondering how teams have solved/ worked around this issue.

[Tesel]

Any tips on making the hovercraft go straight instead of turning sideways or spinning? Wondering how teams have solved/ worked around this issue.

A lot of teams just hug one of the walls of the track so that their hovercraft naturally goes more straight. Another idea is to construct a system to direct the airflow of the thrust fan.

[sjhover]

Thank you, Tesel, for your reply. The issue my team is running into is that the hovercraft hugs one side but because of the power of the thrust fan/ propeller, the hovercraft turns sideways and then stops mid-track. I think weight distribution also plays a part, it starts to turn towards the heavier side, so having even weight distribution helps but we are still trying to nail down going straight consistently.

I guess, directing the flow of the propeller seems to be a good idea and we are already working on that thought. Was wondering if the shape of the hovercraft has any impact on this, having a squarish shape vs a rectangular shape?

[SPP SciO]

Thank you, Tesel, for your reply. The issue my team is running into is that the hovercraft hugs one side but because of the power of the thrust fan/ propeller, the hovercraft turns sideways and then stops mid-track. I think weight distribution also plays a part, it starts to turn towards the heavier side, so having even weight distribution helps but we are still trying to nail down going straight consistently.

I guess, directing the flow of the propeller seems to be a good idea and we are already working on that thought. Was wondering if the shape of the hovercraft has any impact on this, having a squarish shape vs a rectangular shape?

I think I mentioned it earlier and I’m not sure if you tried it, but my students alleviated a similar problem by adding a sail to one side of the vehicle. It’s a quick and easy modification (ours is a file folder cut into a triangle, with plastic straw mast). Someone mentioned about the physics of it; the intake of air from the thrust fan will create lower air pressure on one side of the sail, so the net force will push the sail that direction.

[IvanGe]

what i do is use the penny rolls to even out the weight. I always have it hug the side of the wall. My hovercraft is all removable so I can just adjust my propeller to blow in a slightly different direction during the runs.

[CMS AC]

I find that weight can be used for turning. Can someone confirm?

[Tesel]

I find that weight can be used for turning. Can someone confirm?

That's correct. I believe it's a combination of friction and changes in airflow from the skirt, but moving weight definitely can change how the hovercraft turns.