Help! Kid Hovercraft Build - advice on motors, transmitters, receivers

[lazarski]

Hello,

I am posting this question for my 9 year old son. He asked to post his question to the forum, so I created an account. It is his project not mine. He is responsible for doing the research, finding and asking experts questions and building the project with his team. I am helping if asked.

Hi.

I am 9 years old. I am working on a project with my team for Destination Imagination. We are doing the Technical Challenge. This challenge I have to build a aircraft that fly's 15 feet and drops a payload in a one foot square area. It does this five times.

I am looking at how a hovercraft could be used. In my research on the internet, I found the hovercraft build video by Peter.

Over the last few days, I have learned a lot from Flitetest videos and web site. I have learned a lot about RC airplanes. I have learned about transmitters, receivers, the main board and servos and how they connect to make an airplane fly. I also went to Hobby Town and talked to a worker. it looks fun!

I want to build a hovercraft like this one.

https://forum.flitetest.com/index.php?threads/hovercraft-time-plans-and-photos.56345/#post-441279

I am looking for help to learn what exact motor, props, receivers and transmitters I need.

My team (Team F.B.I - Friend Being Insane) and I, can only spend $150 on this project. We don't have any equipment. My research looks like it will cost at least 200.

Thank you

 

[Dante]

I did DI for a while in 5th and 6th grade, but we never had a project like this in the technical challenge. Ours were usually about building towers that could support as much weight as possible.

About your question- I don't know about what your specific challenge states, but a hovercraft doesn't really hover. It touches the ground very frequently as it usually floats only a few mm above the floor. This may be against the rules. If this does qualify however, I think we need more information about what the payload is. To stay within the $150 budget, that will be hard to do with hobby electronics (especially the transmitter). What my old team did was if we owned anything already, we would value it at what it could be sold for used (which is often way under half the full price).
BTW, your post was very well written and very direct with what you wanted, but I know I did not answer the question . I think we just need more specifications about what you need (rules of the challenge).

 

[mrjdstewart]

define "aircraft" would be my question. does a drone count as "aircraft?" i think it would very possible to pull this off for $150 but without more info can't really help point you in the right direction.

laters,

me

 

[lazarski]

Thank you, Dante and mrjdstwert!

Here are some of the rules of the challenge.

This is the information about the aircraft from Destination Imagination

Design, build a single aircraft that uses technical methods to complete Takeoff, Flight and Landing.
Aircraft: any device capable of flight
Takeoff: when an aircraft goes from being at rest to being airborne.
Flight: the act or process or ability of the aircraft to move while supported by aerodynamic forces or propelled through the air by force. The aircraft can not be considered in flight when touched by any person, object or surface that is not a part of the aircraft itself with the exception of payloads.
Landing: when aircraft is no longer in flight.

From what I have seen on youtube videos and flitetest, it looks like a hovercraft flies. I am pretty sure it flies. 51% sure that it flies.

I think a drone is to expensive, and a plane goes to far and might be hard to drop a payload.

Payload: is any physical item that is loaded on and/or attached to the Aircraft and then carried in flight. Your team may use a different item for each of the 5 different payload drops

During each attempted payload drop the aircraft must carry the payload in the air from takeoff to payload drop. If something other than the aircraft assists in carrying the payload your team risks receiving zero points for that payload drop.

I am not sure what the payload is going to be. The team and i will decide after we know what the aircraft is. We have ideas of payloads

I did DI for a while in 5th and 6th grade, but we never had a project like this in the technical challenge. Ours were usually about building towers that could support as much weight as possible.

About your question- I don't know about what your specific challenge states, but a hovercraft doesn't really hover. It touches the ground very frequently as it usually floats only a few mm above the floor. This may be against the rules. If this does qualify however, I think we need more information about what the payload is. To stay within the $150 budget, that will be hard to do with hobby electronics (especially the transmitter). What my old team did was if we owned anything already, we would value it at what it could be sold for used (which is often way under half the full price).
BTW, your post was very well written and very direct with what you wanted, but I know I did not answer the question . I think we just need more specifications about what you need (rules of the challenge).

 

[Dante]

I wouldn't risk it with a hovercraft. It can go without touching the ground for a couple seconds (maybe), and longer with full scale military hovercrafts, but with small rc versions it will always touch the ground by skimming a little. If it didn't touch the ground at all it would be very unstable and uncontrollable as the lift is extremely hard to get perfectly balanced. If your payload is small like a penny or something you could use a toy drone that has a "flip" function and then put a hook on the bottom. When you get to the drop zone just flip and it will release the item. This may cost you points, however because it is just purchased and only slightly modified.

 

[mrjdstewart]

do you at least know payload weight?

i still think drone is the way to go. not sure how you would make an "airplane" that was able to be accurate enough to hit a 1 sq/ft box, especially if you or your team doesn't have a good pilot.

as for the quad...i think it would be easier, more accurate, and easier to learn in a short time.

4- brushless motors- $23

https://www.ebay.com/itm/RS2205-230...=item214a1c721c:g:EocAAOSwqeVbxe8H:rk:12:pf:0

4- 20A brushless ESC - $24

https://www.ebay.com/itm/4x20A-Brus...pid=2200130610&hash=item3aef9838c4:rk:24:pf:0

Power Distribution Board - $3

https://www.ebay.com/itm/CC3D-Naze3...h=item21239fab9c:g:mWcAAOSwCU1Y3dJL:rk:1:pf:0

Flight Controller - $16

https://www.ebay.com/itm/NAZE32-Acr...=item3633081906:g:O6MAAOSwXFFbk4Oj:rk:18:pf:0

4- 6x4.5 props- $3

https://www.ebay.com/itm/2-Pairs-6-...?epid=521907974&hash=item4897fa9792:rk:4:pf:0

Transmitter with Rx- $60

https://www.ebay.com/itm/Flysky-FS-...3729602373?hash=item3b13767b45:rk:15:pf:0&var

the rest you can build from scratch and shouldn't cost anything. frame can be built out of rulers, balsa, or light aluminum. the only real thing that is still an expense will be the battery. do some youtubing on DIY quads and i think you should be able to pull this off. the above links are just to give you an idea, if you dig you can probably get things even cheaper.

good luck,

me

 

[lazarski]

Thank you Dante!

I read your response. I looked at videos i now see that rc hovercraft touch the ground. They kind of wobble around and touch the ground and are unstable. If they go higher off the ground there is nothing to push against. For my DI challenge its better safe than sorry.

Thank you mrjdstewart!

One idea for our payload is to use damp paper towel or a damp piece of sponge. The weight is 0.21oz. We don't know yet but it can be any thing but it can't break.

Thanks for the links to the parts to the drone. I looked videos about how to build a drone with balsa wood. It looks similar to building a hovercraft - receiver, main board, motors, transmitter - but different. I thought building a drone was too hard. It looks kind of easy now.

If a servo can be attached to a plane, can one be attached to a drone? I was thinking about the glider tow release i saw in a video to release a payload.

rc planes have transmitter with many channels. Do drone transmitters have one channel or many.

Thank you!

do you at least know payload weight?

i still think drone is the way to go. not sure how you would make an "airplane" that was able to be accurate enough to hit a 1 sq/ft box, especially if you or your team doesn't have a good pilot.

as for the quad...i think it would be easier, more accurate, and easier to learn in a short time.

4- brushless motors- $23

https://www.ebay.com/itm/RS2205-230...=item214a1c721c:g:EocAAOSwqeVbxe8H:rk:12:pf:0

4- 20A brushless ESC - $24

https://www.ebay.com/itm/4x20A-Brus...pid=2200130610&hash=item3aef9838c4:rk:24:pf:0

Power Distribution Board - $3

https://www.ebay.com/itm/CC3D-Naze3...h=item21239fab9c:g:mWcAAOSwCU1Y3dJL:rk:1:pf:0

Flight Controller - $16

https://www.ebay.com/itm/NAZE32-Acr...=item3633081906:g:O6MAAOSwXFFbk4Oj:rk:18:pf:0

4- 6x4.5 props- $3

https://www.ebay.com/itm/2-Pairs-6-...?epid=521907974&hash=item4897fa9792:rk:4:pf:0

Transmitter with Rx- $60

https://www.ebay.com/itm/Flysky-FS-...3729602373?hash=item3b13767b45:rk:15:pf:0&var

the rest you can build from scratch and shouldn't cost anything. frame can be built out of rulers, balsa, or light aluminum. the only real thing that is still an expense will be the battery. do some youtubing on DIY quads and i think you should be able to pull this off. the above links are just to give you an idea, if you dig you can probably get things even cheaper.

good luck,

me

I wouldn't risk it with a hovercraft. It can go without touching the ground for a couple seconds (maybe), and longer with full scale military hovercrafts, but with small rc versions it will always touch the ground by skimming a little. If it didn't touch the ground at all it would be very unstable and uncontrollable as the lift is extremely hard to get perfectly balanced. If your payload is small like a penny or something you could use a toy drone that has a "flip" function and then put a hook on the bottom. When you get to the drop zone just flip and it will release the item. This may cost you points, however because it is just purchased and only slightly modified.

 

[mrjdstewart]

yes you can hook a servo to a drone. you could power off the PDB, or just plug into your RX on the gear channel, then use your gear switch on Tx to control it. i would recommend a setup like the FT Cub 3-channel bomb drop arrangement. very simple, sturdy and easy to reload. also check out the FT Dart power setup, very similar to what you will be doing.

good luck,

me

 

[Dante]

By the way mrjdstewart knows way more than me and as such may not have realized what you would know. I only recently learned what many of these are->
PDB= power distribution board (all the power wires get soldered onto here)
RX= receiver
Tx =transmitter (controller you hold)
If you already know these terms- great you know way more than I did at 9 yrs old! (i'm 16)
Just trying to help!

 

[Land Shark]

@lazarski, please keep us updated! I'm curious as to how it goes, and it's great that you are doing this at 9! I'm 13 and am trying to successfully get a plane in the air. Whatever happens, have fun with it. I've crashed 2 of 2 planes that I scratch built. Know that crashing is completely normal and if you have any questions, come back to the FT forums. I personally am not a drone person, but there are many friendly people here that are more than willing to help.

 

[lazarski]

Thanks a lot everyone for the help - its a lot less confusing. still have to find the right battery and explain it to my team.

 

[buzzbomb]

I am also new to all this, but I had a thought and thought it might inspire your thoughts... Yeah, I know. I'm not nine years old, I just act like it.

Check out the Furibee F36. It comes with a transmitter and receiver and you can get one from Banggood for about ten dollars. Your timeframe probably won't allow for shipping from China, but check out domestic resellers on Ebay and Amazon. The batteries are just a few dollars each, and I think I paid about ten bucks for the charger.

It's strong enough to support a little container on the top with a lightweight "payload" in it, and it will flip over and come back upright with a button push. You've got near everything needed in that little package only you neither designed nor built it. OK. Disassemble it. Design and build a new quad frame for it.

Just a thought.

This is an edit: It does it's flip really fast. You'd have to put some serious thought into how NOT to fling the payload across the room!

Here's another edit. You've really got me thinking about this fun project you've got! It's not hard to picture a simple string with a bent paperclip "hook" and a payload with a wire hoop on the top. You lift with it, fly to wherever, and just lower the quad to disengage. Just more thoughts.

 

[FoamyDM]

I was thinking of the same thing as buzzbomb.... but with that budget, you CAN HAVE FOUR, and CARRY THEM IN BETWEEN!

 

[mrjdstewart]

i think part of this is to build it, not just buy commercially available stuff. if that was the case, the rich kid would win everyone. oh, wait...



me