Lynxmotion Tech Support

The goal of this topic is to show how anyone can make a custom 2.4ghz radio system for robotics. I'm using gimbals (joysticks) from an old Laser 4 radio. The transmitter will be a Spektrum airmod which is a modular 2.4ghz transmitter that accepts a simple PPM data stream. The airmod module binds to a specific receiver (robot) just like the Spektrum radios do. The system will be prototyped with an Atom Pro processor. I may design a board for an Atmel chip later. The best part is I will be using channel 5 and 6 to support a couple 16 key keypads for controlling many functions or physical devices on the robot end. I may add a serial LCD as well.

Well here is the radio top panel version 1.00.



The panel fits an injection molded box that I ordered today. I have lots more work to do to it, but it's a start.

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Jim Frye, the Robot Guy
http://www.lynxmotion.com
I've always tried to do my best...

Make certain you don't turn the AIRMOD on without an antenna attached... they are quite emphatic about that in their documentation.

I was going to throw up a keypad link from sparkfun but upon thinking about it they really milk the heck out of the cost of a complete assembly so... I am sure there are plenty of economical options available.

Ah! It looks great Jim.

It seems to be much easier to place/fit a keyboard too.

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[b]Kåre Halvorsen, Zenta[/b]
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Zenta's blog
http://zentasrobots.com/
Zenta's YouTube channel
http://www.youtube.com/ZentaOlbaid
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Hey EddieB which airmod were you going to use? I'm looking at the DSM2 AIRMOD w/AR7000 FUT-Compatible [SPMMSFUT7] it looks like this.



This is the receiver.



It's priced at $109.99 for the transmitter module and the receiver, where the receiver alone is priced at $99.99. It's ordered, just waiting for it to arrive.

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Jim Frye, the Robot Guy
http://www.lynxmotion.com
I've always tried to do my best...

lol. well the AR7000 is for big electric and IC planes so I dunno if you needed it but the different modules can be bound to transmitters supporting the same DSM / DSM2 protocol so it's not a big deal. The AR6100 receiver seems like it would be the better choice to put in a brat or a scout though just because it's smaller... plus I can use it in my planes. Oh wait did that slip out?

Actually the combination you picked seems to be the lowest price so it is probably what I'll buy... and maybe an AR6100... oh wait... um... did you consider that you may be able to cut/mill a pocket in the top plastic there to let the module snap in place just like on a r/c radio? You could quite literally just scre the antenna onto it's output connector without needing to mount the thing internally and provide a mount for the antenna.

Well there were a few things that sort of made the decision for me. The first being they don't offer any of the airmods with that receiver. You basically get the AR7000 for $10.00 though. It's got to have the best reception which will be important with the open loop nature of the keypad functions.



Yes I plan to try to make the top panel so the transmitter will snap in if possible. I don't think the airmods actually includes the antenna. I will know soon enough. I have some 2.4ghz antennas left over from the BlueSmirf projects.

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Jim Frye, the Robot Guy
http://www.lynxmotion.com
I've always tried to do my best...

Fantastic design. So much room for so much more!

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Mike

The robotics nut.

The user manual on the Spektrum site suggests one or more antennas come with the modules to fit the different radios they are intended to be installed in. Looking at the pictures it might be more work to use those than a normal 2.4GHz stubby.

Yeah I wasn't able to find any definitive image or text of "what's included." I was able to find an external antenna available separately.

On another subject. I have been looking around for some cool 16 key keypads. I found one that has insertable legends! From here.

http://www.unimaxswitch.com/Unimax11.htm



But I haven't been able to find a price on them yet.

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Jim Frye, the Robot Guy
http://www.lynxmotion.com
I've always tried to do my best...

Hey these are ok too. No way to change the labels on the keys, but ridiculously inexpensive at $4.40 each. lol

From here... http://www.futurlec.com/Keypads.shtml

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Jim Frye, the Robot Guy
http://www.lynxmotion.com
I've always tried to do my best...

I like the ABCD buttons. I'm curious about the price of the insertable key pads. Spark Fun had dynamic display buttons a while back where each button had its own LCD display.

_________________
Mike

The robotics nut.

Here is one that looks like the keys can be labeled.



From here...
http://www.comfiletech.com/index.asp?PageAction=VIEWPROD&ProdID=55

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Jim Frye, the Robot Guy
http://www.lynxmotion.com
I've always tried to do my best...

And so it continues! Great job Jim!

I like the keys with the label, this really makes it universal!

I went ahead and ordered some of these for the prototype. I like the 0-9 A-F anyway...



From here.

http://www.elexp.com/cmp_1604.htm

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Jim Frye, the Robot Guy
http://www.lynxmotion.com
I've always tried to do my best...

Thats a great choice. It has .1" pin spacing and I like the hex array numbers as well.

It looks like it will mount nicely on the radio chassis.

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Mike

The robotics nut.