Arduino Anyone?

[BrittanyGulden]

Curious to see whom on this forum has ever worked with one & if anyone is even familiar with them.

Thanks!

 

[bobhaha]

Yup... a lot of us have... They are used pretty often for all different applications.

 

[BrittanyGulden]

Sweet!

I have seen a few guys use Arduino boards on their RC Vehicles. -Specifically an RC Heli which I think would make a neat project.

Before I fail to get into details (lol), what makes up an RC Vehicle?

-Transmitter
-Receiver
-"Q" -Not sure if this is the correct term, but it enables the same frequency signal to be sent between the transmitter & receiver.
Power Supply
Servo's


^Just what exactly are the "brains" of the RC Vehicle? What is it called? -Or is it built in the reciever itself?

 

[bobhaha]

Most RC vehicles are composed of these parts:

RC reciever/mixer
Servo's
Speed controller
Motor
Battery

Basically the RC receiver picks up the signal from the transmitter then outputs a PWN signal to the speed controller (also called ESC) which receives that signal and translates that into a relative speed for the motor.

The next part is kinda tricky. Some RC systems can use serial connections to the servos where a specific number is sent to the servo and the servo converts it to a degree value and moves to the position. Another way the servos work (Which is the most common) is using PWM to get a value between (typically) 0 and 255 then mapping that value between 0 and 180 degrees in order to move the servo to that position. So for example 0 PWM signal will be 0 degrees or 200 PWM signal would be 141 degrees.

Also I'm not sure what you mean by "Q" but it sounds like you are talking about the frequency crystals that are used to pick up specific frequencies for both transmitters and receivers. But now with 2.4Ghz technology each receiver has its own MAC address which the transmitter locks on to. That way you can have multiple RC vehicles working off 2.4Ghz transmitters and not getting interference. This also means you can have one transmitter for multiple RC vehicles.

 

[lasersbee]

Actually most analogue servos (the inexpensive ones) are controlled
by a pulse train that is sent to them with a PWM pulse of between
1ms and 2ms... At 1.5ms the servo is centered.

ESCs or Electronic Speed Controls are sent the same signals and are
controlled in the same way..


Jerry

 

[bobhaha]

Hmmm I may be playing with old technology here...

As for the servos, I only have access to digital servos ($30 each... granted they are metal gear) which use a serial input or PWM signal.

But that would make sense since I can't get a servo movement from the motor pins... So you could be right.

 

[lasersbee]

Here's a .PDF that will help explain servos and controlling
them.....:beer:

http://www.princeton.edu/~mae412/TEXT/NTRAK2002/292-302.pdf


Jerry

 

[BrittanyGulden]

Thanks for the info guys. ...Man another month or so of researching yet another project.

So how are servo's broken up? -What categories? It appears as there are many types of servo's. (3 examples were listed above, or atleast 3 different types of signals being sent) However, I am only assuming there is really only 2 correct? -Analogue ...& digital?

What do you mean "the servo is centered?"

So where does the Arduino come into play?

It appears as an Arduino would act as a substitute for an ESC. -If this is correct than I do not see any advantages of using an Arduino board. -Maybe they are cheaper?

However, if an Arduino board can act as both a Recieiver & ESC, than I could see an advantage, especially considering the possible features one would have W/ an Arduino board.

-I just came across a small reading on how Arduino boards WERE used as "receivers" & Wii controllers were used as transmitters. ...hm Wifi?


Yes, when I meant "Q" I was talking about the Crystals.

2.4Ghz technology? -This is where I am lost. I just did a search & the only thing that came up was different electronics.

 

[GoolGaul]

I have been tinkering with Arduino for a little while now. Working on some clock-related
concepts...

the nice thing about Arduino & it's associated community is the sharing on know-how. The community is the only one that I know of that is more willing to share more hard-thought knowledge than this site is... (and the folks here are pretty generous with their know-how)

There are libraries for almost anything that you can plug in...

 

[GoolGaul]

-So where does the arduino come in to play?

in all reality, in the average R/C device, there is no need for an arduino... it;s when you want to automate it, GPS it, take pics with it, control LED's on it, and so on...

you'd be better off determining what you want to do with your R/C vehicle, then use the Arduino as the solution, then when you see you have leftover pins and processor power, you can start expanding "for the hell of it"

(I'm in the problem solving stage, but I am already looking at the "for the hell of it" possibilities)

 

[BrittanyGulden]

in all reality, in the average R/C device, there is no need for an arduino... it;s when you want to automate it, GPS it, take pics with it, control LED's on it, and so on...

you'd be better off determining what you want to do with your R/C vehicle, then use the Arduino as the solution, then when you see you have leftover pins and processor power, you can start expanding "for the hell of it"

(I'm in the problem solving stage, but I am already looking at the "for the hell of it" possibilities)

You may have came across my "DIY Nightvision" thread(s). I plan on building an RC Helicopter, but W/ a twist. I want the ability to fly my RC Helicopter at great-er distances. I was thinking about attaching a small (or series of) wireless security camera to my RC body & have a signal sent to my transmitter (Remote) where a screen would be held as a way to visualize. -It'd be somewhat like a handheld simulator. I think it'd be super neat to fly this at night. This is where my "DIY Nightvision" comes into play


A GPS would be VERY handy, especially when I can not physically see my RC Heli. Pics, video, the list goes on. Super Super cool.


I want to look into the Arduino because of it's possibilities.

Btw, I am also looking for some "eco-friendly" ways of powering my RC Heli. I want this Vehicle to be quiet, so electric looks like the way to go. However, what sucks about RC Vehicles? -They ALWAYS run out of power. I am tossing around ideas on how to lengthen my power supply.

-I have a few options. I have 2 huge rotor blades above my vehicle pushing out some serious "windage" (lol) & I have multiple servo's. Now I need to find a way to capture/harness that energy. Weight will be an issue here. Ha, I've been studying the Prius lately & came to the conclusion that thermodynamics sucks. -There has to be some form of energy that can be amplified W/ loss..... One day, it will be found!

^Hm, LOL I'm battling perpetual motion & so far im loosing

 

[lasersbee]

It is called FPV (First Person View).... you can get more
detailed info on it by searching FPV RC on Google...

This is basically a Laser Forum... some members also
fly/drive/boat/sail RC...

You can get some ideas on this site... It an FPV plane but
the FPV info is interesting and there are some videos...


Jerry

 

[BrittanyGulden]

Thanks for the heads up.

Yeah, I figured I'd just drop in & ask. -Some pretty sharp people on here

 

[lasersbee]

I forgot to add the FPV Link...

HobbyKing R/C Hobby Store : EPP-FPV 1.8M X-Large EPP & Carbon Fiber R/C Plane

Go near the bottom of the page for the videos..:beer:


Jerry