Hello, I'm a high school student interested in robotics and I just started my first project with some friends, but we're complete beginners so we're having trouble figuring out how to go about turning this idea into a reality..
Basically, we want to construct a speaker "ball" that we will be able to increase and decrease in size via bluetooth. We already have a spherical wireless speaker with bluetooth connectivity and we need to construct the rest of it.
So far, our best idea is to attach the speaker we have to a Hoberman sphere using elastic materials and also a bluetooth controlled antenna or antennas (aerials) that we will be able to extend and retract using a mobile app we will also build.
My friend is doing the coding and I'm responsible for the construction. I have little knowledge about anything like this and have just begun reading about robotics, so if someone can help point me in the right direction it would be greatly appreciated. Also, if anyone knows about what tools would be better to construct this or if this has been talked about before, please share any of it with me.
Thank you!
Do you mean you’re going to
Do you mean you’re going to make a flying blimp propoganda machine or are you just making a funny sphere that changes its size and which also has a speaker? The first one will be a hell of a ride to make (I’d even suggest making a quadcopter instead - less costly gaz involved, no worries about perforation, etc.), and the latter, well I’m not even sure I understand it correctly.
Uhm okay from what I gather
Uhm okay from what I gather it will probably be the second option because I don’t think anything with a heavy Hobberman sphere will fly. Then I guess you don’t actually need huge antennas, and it puzzles me why they would need to be able to retract.
Aha - I think you want to
Aha - I think you want to transmit data a very long way. Then use this - compact and no need to retract/extract.
http://www.antenna-theory.com/antennas/travelling/spiral.php
But, I think bluetooth has a limited range, typically less than 40 feet. I think you won’t be needing a huge antenna to pick up bluetooth at such a distance. It seems like bluetooth devices have are loew-power so they have such a short range. Maybe some non-standart ones can go further, but I’d bet your speaker has a standart bluetooth interface.
What I’d try in the case
What I’d try in the case that you want a long-range propaganda sphere, is to implement the entire thing using RF transmitters. I personally have a pair of APC-220 that claim to transmit up to 9600 bps (not sure if bits/s or bytes/s) at a max range of 1000m (don’t know if legit or not). At 800 bits/s you can achieve recognisable speech. At 1400 bits/s there’s an open-source codec available (Codec2). I’m guessing - just guessing that maybe you could so something with an arduino and a speaker. It’s more of an extra job for the programmer.
At least he can boast about
At least he can boast about it later.
Thanks for all the
Thanks for all the replies!
Flying would be amazing, but for now I simply just want a spherical structure (with a speaker in the center) that can increase/decrease in size depending on the volume of the music. Are there antennas out there that can be connected to and controlled via bluetooth? Or anything else I could use to expand/retract?
With your new reply
it would seem you don’t need to read the BT data (more difficult) as much as you need to read the amplitude of the sound going to the speaker (easier). It seems like what you are doing is building a VU meter that is a sphere instead of a bar graph. All you really would need to do in that case is read up on arduino based VU meters and then figure out how to actuate the ball properly.
