Society of Robots - Robot Forum
Electronics => Electronics => Topic started by: CdRsKuLL on July 17, 2012, 09:12:25 AM
-
I've started to design my own bot.. :-) I'm about 25% done on the design and when complete it will be printed out on my 3d printer I made.
(http://www.freeice.co.uk/images/newbot.jpg)
This is yesterdays images... I'm now adding some servos to the feet :-)
Anyway.. room is a little tight but I need it to meet the following requirements.
Wifi controllable (writing a vb.net frontend with a bit of flash thrown in)
Arduino based robot as I have some knowledge coding it.
I need it to control upto 16 servos I think but would also like some sensors on it.. maybe a gyro 3 axis for starters so it knows when it falls over.
So.. wifi / 16 servos / 3 axis gyro and some other sensors (no idea what yet).
Anyone care to take a stab ?
-
Nothing constructive to add, but I'm imagining trying to control that thing and having flashbacks to QWOP (http://www.foddy.net/Athletics.html). :)
-
I've just received my MMA7361 Three Axis Accelerometer which I've rigged upto my Arduino nano.. wrote a quick vb.net to check I can read the values via the comport. :-) very pleased so far.. BUT
I need to control around 16 servos and read the tilt. I also want to be able to send the info back via wifi to my PC and control the bot from it. The wifi will be using the uart serial but I'm guessing the 16 servos will need a servo board. I've not gone too much into it as yet but I'm worried I'm going to run out of pins !!
The MMA7361 uses the A0 to A3 pins and the Aref. The wifi will use the tx and rx pins but I think this controller http://www.ebay.co.uk/itm/32-Channel-Servo-USB-Controller-board-for-arduino-MCU-PIC-/250998651279 (http://www.ebay.co.uk/itm/32-Channel-Servo-USB-Controller-board-for-arduino-MCU-PIC-/250998651279) also uses the same port.
Can anyone confirm if I'm ok trying to use all this things or if infact I'm knackered and need to go down another root before I start buying everything?
I'm using a nano because space it tight and everything needs to go inside it's body.
thanks,
Steve
-
This is a very ambitious project :)
I would caution you to take it slow, rather than trying to do everything at once.
What servos are you using?
I would start without the arms, and tether the bot rather than worry about wifi. Your first challenge will be to make sure that the printed legs + body parts aren't too heavy for the servos you're using...
I don't use hobby servos any more, so I can't help you with good ways to control lots of servos.
-
Hi, many thanks for your reply... I completely agree about the size of the project :-)
The printed parts will be quite light with the foot just weighting in at about 12grams and the lower leg about 15grams minus the servos. So I'm expecting the whole bot to be about 750g including batterys etc.. The servos I've ordered are MG90S ones which say they have a 2.2kg/cm(6V). No idea if this is strong enough or not. :-) time will tell.
I've re-re designed the feet now and legs to try and improve the print and also the movement.
I will be taking it slowly.. build the legs then a body and just code up the ardunio to see if I can get him to move a little. The main movements will be coded into the arduino.. ie kneel / walk / bend / wave etc.. and I'm hoping to code in some anti-collison so that it knows say it cant put its arm at position X as it's leg is already there.
Unsure on sensors but Ive got some ultrasonics coming and some tri-colour led's for eyes.. lol It's got a gyro so knows what position it's main body is in.
one step at a time :-) going to print a leg today if I get chance .. lol
more to come..