Embedded Ethernet?

[Andrew Blair]

In my quest for an interesting and challenging senior project, I have begun to look into building a small remotely/autonomously operated rc car. The idea is this: run a slave Ethernet controller(connected to rc car's motors, perhaps a sensor or two) and webcam through a wireless router and voila!- poor man's robot controller, only inverse. A computer with wireless takes all the data from the webcam and Ethernet device and sends back instructions.

So you say: Andrew, why not just cruise Ebay and pick up a $20 computer that already has Ethernet capability? Problem is, I then have to build a serial/USB/parallel motor/sensor controller, all just to relay the data back to another computer. Plus, I have to build a larger robot to haul that heavy piece of silicon antiquity around. So weight/size is at a premium.

Bottom line- If I decide to pursue this, I need a small, light, and most of all, cheap, ethernet controller to act as a slave. I've looked at Rabbit, NetBurner, Ethernut, and some others, and the best price I've seen is $150 from Rabbit. Maybe Mini-ITX would work. Any ideas?

[BrianBSL]

Originally Posted by Andrew Blair

In my quest for an interesting and challenging senior project, I have begun to look into building a small remotely/autonomously operated rc car. The idea is this: run a slave Ethernet controller(connected to rc car's motors, perhaps a sensor or two) and webcam through a wireless router and voila!- poor man's robot controller, only inverse. A computer with wireless takes all the data from the webcam and Ethernet device and sends back instructions.

So you say: Andrew, why not just cruise Ebay and pick up a $20 computer that already has Ethernet capability? Problem is, I then have to build a serial/USB/parallel motor/sensor controller, all just to relay the data back to another computer. Plus, I have to build a larger robot to haul that heavy piece of silicon antiquity around. So weight/size is at a premium.

Bottom line- If I decide to pursue this, I need a small, light, and most of all, cheap, ethernet controller to act as a slave. I've looked at Rabbit, NetBurner, Ethernut, and some others, and the best price I've seen is $150 from Rabbit. Maybe Mini-ITX would work. Any ideas?

Microchip and others make SPI to Ethernet controllers (such as the ENC28J60), which when paired with a microcontroller should suit your needs - and for far less than $150. It will require some engineering work, as you get just the chip, have to add magnetics for the physical interface, and write all the code for it (although I'd imagine some example code is available online).

[Zak698]

The code for the micrcontroller is not that hard, currently i am working at microchip (sitting at my desk right now) doing programing for microcontrollers. Brian's idea is a grate idea, the Microchp pic would be able to halde it. my suggestion would to be to go with the PIC18F seris, with that you will be able to do a lot more stuff and expand upon it later, but the PIC16F's will also work for what you need it to do, if you need any help with this feel free to reply, but you will have a better chance to get ahold of me via email (zak.priddy@gmail.com)... Good Luck!
Oh, i forgot to mention, i have done a similar project, but mine was controlled via parrell and was contollable via internet, this way you could monter something while you are away... again, if you need help feel free to contact me.

[bear24rw]

Parallax has a board that can be interaced with a basic stamp...

http://www.parallax.com/detail.asp?product_id=30013

[edit] I just realized that it is not wireless, but it's worth a look at anyway [/edit]

[Astronouth7303]

If you can get a copy of Robot Magazine issue 1 (winter 2005), it has an article about how to create a RC tank based on WiFi and a web interface (CGI). In issue 2 (spring 2006), he makes it run on AJAX.

Maybe you can use some of that in your project. Their website is http://www.botmag.com/ (You can also order back issues, since they don't post them on their website yet.)

[Tom Bottiglieri]

www.gumstix.com

They have ethernet and Compact Flash card slots. You can buy a compact flash WiFi card for pretty cheap.

Best of all, they run linux.

[Andrew Blair]

Errr... this is probbably way out of my league, but how impossible would it be to build/code a wifi transmitter/reciever? Is the hardware end as easy as an adjustable oscillator driving an antenna and a microcontroller to control the the whole protocol deal after that? Would a PIC be able to handle it all? Wifi architecture is rather interesting, but insanely difficult to work with I'd imagine.