Hovercraft B/C

User avatar
windu34
Exalted Member
Exalted Member
Posts: 907
Joined: Mon Apr 20, 2015 1:37 am
Division: Grad
State: FL
Location: Gainesville, Florida
Contact:

Re: Hovercraft B/C

Postby windu34 » Thu Jan 05, 2017 6:51 pm

Zioly wrote:I've been looking for a thrust fan. Would this one fill the niche?

https://www.youtube.com/watch?v=rLmxUP4Dku4
http://www.digikey.com/product-detail/e ... ND/5209819

Same fan. One is a video I found of it.

looks good to me
President of Science Olympiad at the University of Florida || Boca Raton Community High School Alumni
SONT 2016: 2nd place in Electric Vehicle || 3rd place in Robot Arm
SONT 2017: 2nd place in Electric Vehicle || 5th place in Invasive Species
Jazzin710@gmail.com
windu34's Userpage

User avatar
sciduck
Exalted Member
Exalted Member
Posts: 83
Joined: Sat May 07, 2016 11:50 pm
Division: C
State: MN
Location: Wayzata
Contact:

Re: Hovercraft B/C

Postby sciduck » Sat Jan 07, 2017 3:27 am

Do I have to know gas laws for the test? Not sure if it's w/n the fluid mechanics topic or not...
SCIDUCK wants to fight!
———————————————
SCIDUCK uses CONFUSION!
———————————————

User avatar
windu34
Exalted Member
Exalted Member
Posts: 907
Joined: Mon Apr 20, 2015 1:37 am
Division: Grad
State: FL
Location: Gainesville, Florida
Contact:

Re: Hovercraft B/C

Postby windu34 » Sat Jan 07, 2017 5:57 am

sciduck wrote:Do I have to know gas laws for the test? Not sure if it's w/n the fluid mechanics topic or not...

No
President of Science Olympiad at the University of Florida || Boca Raton Community High School Alumni
SONT 2016: 2nd place in Electric Vehicle || 3rd place in Robot Arm
SONT 2017: 2nd place in Electric Vehicle || 5th place in Invasive Species
Jazzin710@gmail.com
windu34's Userpage

RJohnson
Member
Member
Posts: 49
Joined: Mon Apr 04, 2016 3:47 pm
Division: C
State: OH
Contact:

Re: Hovercraft B/C

Postby RJohnson » Sat Jan 07, 2017 6:36 pm

What are people using for shielding their fans? I've been using gutter protectors because I had them laying around, but the performance loss is significant... Has anyone had any success with other materials that they're willing to share?

Thanks!

User avatar
windu34
Exalted Member
Exalted Member
Posts: 907
Joined: Mon Apr 20, 2015 1:37 am
Division: Grad
State: FL
Location: Gainesville, Florida
Contact:

Re: Hovercraft B/C

Postby windu34 » Sat Jan 07, 2017 7:07 pm

RJohnson wrote:What are people using for shielding their fans? I've been using gutter protectors because I had them laying around, but the performance loss is significant... Has anyone had any success with other materials that they're willing to share?

Thanks!

I have tried a few materials, but in the end, the loss is pretty much the same. Bottom line is the fan needs to be powerful enough to overcome it
President of Science Olympiad at the University of Florida || Boca Raton Community High School Alumni
SONT 2016: 2nd place in Electric Vehicle || 3rd place in Robot Arm
SONT 2017: 2nd place in Electric Vehicle || 5th place in Invasive Species
Jazzin710@gmail.com
windu34's Userpage

Patrick Yepes
Member
Member
Posts: 6
Joined: Sat Oct 22, 2016 1:35 am
State: -
Contact:

Re: Hovercraft B/C

Postby Patrick Yepes » Sun Jan 08, 2017 6:40 am

windu34 wrote:
HandsFreeCookieDunk wrote:I did an estimate by scaling down larger hovercraft propellers and found that you'll need about 50 CFM to go full speed with a 2kg craft. Does this sound reasonable?

Very reasonable, but keep in mind our hovercrafts will not be very comparable and youll likely need much more CFM. There is a fan on amazon with 200 CFM for a reasonable price.
I attached a grate/mesh over the propulsion fan that I laser-cut out of acrylic. Reduces thrust by ALOT. Might have to look for a different solution.
What have you guys tried as far as materials for the grate?



Isn't it against the 'rules' to laser cut something for the hovercraft since the students don't have a hand in the design, programming, or using the machine to cut said part?

Asking for a friend... ;)

bearasauras
Member
Member
Posts: 284
Joined: Wed Mar 05, 2003 4:33 am
State: -
Location: Pasadena, California
Contact:

Re: Hovercraft B/C

Postby bearasauras » Sun Jan 08, 2017 6:57 am

I think windu does the laser cutting on his own. NSO has policies for how much adults should be involved: https://www.soinc.org/building-and-tools-policy

User avatar
windu34
Exalted Member
Exalted Member
Posts: 907
Joined: Mon Apr 20, 2015 1:37 am
Division: Grad
State: FL
Location: Gainesville, Florida
Contact:

Re: Hovercraft B/C

Postby windu34 » Sun Jan 08, 2017 7:28 am

Patrick Yepes wrote:
windu34 wrote:
HandsFreeCookieDunk wrote:I did an estimate by scaling down larger hovercraft propellers and found that you'll need about 50 CFM to go full speed with a 2kg craft. Does this sound reasonable?

Very reasonable, but keep in mind our hovercrafts will not be very comparable and youll likely need much more CFM. There is a fan on amazon with 200 CFM for a reasonable price.
I attached a grate/mesh over the propulsion fan that I laser-cut out of acrylic. Reduces thrust by ALOT. Might have to look for a different solution.
What have you guys tried as far as materials for the grate?



Isn't it against the 'rules' to laser cut something for the hovercraft since the students don't have a hand in the design, programming, or using the machine to cut said part?

Asking for a friend... ;)

I complete the entire fabrication without any assistance from my coach which includes 2D and 3D modeling in AutoCAD, exporting the file to the Retina Engrave software, calibrating the laser cutter, and supervising the actual cutting of the acrylic.
Glad you are familiar with the policy
President of Science Olympiad at the University of Florida || Boca Raton Community High School Alumni
SONT 2016: 2nd place in Electric Vehicle || 3rd place in Robot Arm
SONT 2017: 2nd place in Electric Vehicle || 5th place in Invasive Species
Jazzin710@gmail.com
windu34's Userpage

SPP SciO
Member
Member
Posts: 177
Joined: Tue Mar 24, 2015 3:21 pm
Division: B
State: NY
Location: Brooklyn
Contact:

Re: Hovercraft B/C

Postby SPP SciO » Sun Jan 08, 2017 5:48 pm

With propulsion fans: has anyone had experience with removing the propeller from a CPU fan and attaching it to the shaft of a DC motor? We were able to grab a bunch of old CPU fans from an e-waste recycling center and are thinking of experimenting. We've tried DC motors with a drone style propeller (on a simple alkaline 9v circuit) and it doesn't do the trick.

Basically - would we have more luck switching the drone prop for a wider, steeper pitched prop? Or trying to attach a computer fan prop to a motor? Or should we use the computer fan for propulsion "as is" because the propeller is optimized for that particular motor? The 12v fans don't seem to produce much airflow with 9v batteries.
Coach
MS 821 Sunset Park Prep
http://www.sppscio.com

User avatar
windu34
Exalted Member
Exalted Member
Posts: 907
Joined: Mon Apr 20, 2015 1:37 am
Division: Grad
State: FL
Location: Gainesville, Florida
Contact:

Re: Hovercraft B/C

Postby windu34 » Sun Jan 08, 2017 7:37 pm

SPP SciO wrote:With propulsion fans: has anyone had experience with removing the propeller from a CPU fan and attaching it to the shaft of a DC motor? We were able to grab a bunch of old CPU fans from an e-waste recycling center and are thinking of experimenting. We've tried DC motors with a drone style propeller (on a simple alkaline 9v circuit) and it doesn't do the trick.

Basically - would we have more luck switching the drone prop for a wider, steeper pitched prop? Or trying to attach a computer fan prop to a motor? Or should we use the computer fan for propulsion "as is" because the propeller is optimized for that particular motor? The 12v fans don't seem to produce much airflow with 9v batteries.

I don't have much experience working with any of those types of propellors/fans so Id recommend trying all the combinations. More importantly, you must transition away from 9V batteries and use either 7.2/8.4 V NIMH or 7.4V LiPo BATTERY PACKS. The amount of current a alkaline battery produces is nowhere near what you need to supply to the motor
President of Science Olympiad at the University of Florida || Boca Raton Community High School Alumni
SONT 2016: 2nd place in Electric Vehicle || 3rd place in Robot Arm
SONT 2017: 2nd place in Electric Vehicle || 5th place in Invasive Species
Jazzin710@gmail.com
windu34's Userpage

User avatar
antoine_ego
Exalted Member
Exalted Member
Posts: 152
Joined: Wed May 25, 2016 12:37 am
Division: C
State: MA
Location: Acton Boxborough Regional High School
Contact:

Re: Hovercraft B/C

Postby antoine_ego » Sun Jan 08, 2017 11:08 pm

Considering that no one has asked this yet, what scores have y'all gotten when testing your hovercrafts?
2016: MIT: Air Trajectory 16th; Astronomy 19th; WIDI 12th
Nats: Air Trajectory 3rd; Astronomy 21st; Protein 27th
2017: MIT: Astronomy 10th; Hovercraft 8th; Optics 20th

User avatar
Adi1008
Member
Member
Posts: 293
Joined: Fri Dec 06, 2013 9:56 pm
Division: C
State: TX
Location: Katy, Texas
Contact:

Re: Hovercraft B/C

Postby Adi1008 » Sun Jan 08, 2017 11:21 pm

antoine_ego wrote:Considering that no one has asked this yet, what scores have y'all gotten when testing your hovercrafts?

I think it's hard to tell because of the mass score. It depends on the heaviest device at the competition, so people's scores will vary. At a very competitive competition, someone might have a low mass score, while at an uncompetitive tournament they might have a very high mass score
Seven Lakes High School '18
His dream must have seemed so close that he could hardly fail to grasp it; it eluded us then, but that's no matter, for tomorrow we will run faster, stretch out our arms farther

HandsFreeCookieDunk
Member
Member
Posts: 81
Joined: Fri Jan 15, 2016 12:53 am
Division: C
State: PA
Contact:

Re: Hovercraft B/C

Postby HandsFreeCookieDunk » Mon Jan 09, 2017 3:29 pm

Adi1008 wrote:
antoine_ego wrote:Considering that no one has asked this yet, what scores have y'all gotten when testing your hovercrafts?

I think it's hard to tell because of the mass score. It depends on the heaviest device at the competition, so people's scores will vary. At a very competitive competition, someone might have a low mass score, while at an uncompetitive tournament they might have a very high mass score


I think it's pretty safe to assume that most competitions will have at least one 2kg device.

JonB
Coach
Coach
Posts: 234
Joined: Tue Mar 11, 2014 7:00 pm
Division: C
State: FL
Contact:

Re: Hovercraft B/C

Postby JonB » Mon Jan 09, 2017 3:45 pm

Patrick Yepes wrote:
windu34 wrote:
HandsFreeCookieDunk wrote:I did an estimate by scaling down larger hovercraft propellers and found that you'll need about 50 CFM to go full speed with a 2kg craft. Does this sound reasonable?

Very reasonable, but keep in mind our hovercrafts will not be very comparable and youll likely need much more CFM. There is a fan on amazon with 200 CFM for a reasonable price.
I attached a grate/mesh over the propulsion fan that I laser-cut out of acrylic. Reduces thrust by ALOT. Might have to look for a different solution.
What have you guys tried as far as materials for the grate?



Isn't it against the 'rules' to laser cut something for the hovercraft since the students don't have a hand in the design, programming, or using the machine to cut said part?

Asking for a friend... ;)



As the coach, I can confirm that he does all of his own work, from start to finish. The laser cutter is available for student use in my classroom. I am here to make sure we don't all catch on fire and to fix it when it breaks.

HCCoach
Member
Member
Posts: 6
Joined: Mon Jan 02, 2017 9:37 pm
State: -
Contact:

Re: Hovercraft B/C

Postby HCCoach » Mon Jan 09, 2017 8:18 pm

windu34 wrote:
RJohnson wrote:
sciolyqa wrote:What is the part number of the motor from digi-key that suffice? We have been there and must have missed that.

Here is the link: http://www.digikey.com/product-detail/e ... ND/2560506

That is a really good looking blower! Specs are definitely above the requirement



Hello, Has anyone used this fan for lift?
Isn't this a bit too big?
Thanks!


Return to “2017 Lab Events”

Who is online

Users browsing this forum: No registered users and 1 guest