Been awhile

It's been awhile since I've posted. Been dealing with a bad case of strep throat, and getting better now.  Looked into getting the 6v motors for Leo, but it will have to wait till I want some other stuff from Polulu.com. If I order now, I get 4 motors for $20 and if I wait till next month I can order 15 motors for just over $30. They are inexpensive, but the S&H is not.

Going to order the replacement L293D for the drive board and a few other things tonight from BGMicro. I have a few ideas I'm working on. IF they pan out, I will blog about them, if they fail....well if it's spectaculiar, I'll publish the film and if not ah well, you will never know *wink*

Mech outta here

Current projects

My current projects since Leo is almost physically complete are building up 4 arduino clones with a few personal additions and a few things like dual H-bridges with opto-couplers, IR sensor board(yes, I know you can buy sharp sensors ready to plug in to the MCU).   I got the magnets for the magnetic encoders, just have to find some bipolar hall effect sensors such as the 1302, which is found in the tachometer gear of most cars.  Found some on Ebay.com, but was hoping to support the local economy first before the world economy.

Leo is almost physically complete. Just need to wire up the IR sensors and get the hall effect sensors. Once those are installed the body part is done. After that I will switch out his motors for 6v ones and maybe add a head with some sensors on it.

Mesmic 2125

Was looking around Radio Shack last Friday and found a Mesmic 2125 accelerometer in the sensor bin, I also found a PING module from parallax too. Got the accelerometer, but not the PING module. I like to stay within a budget and I think I can find the sonic module cheaper online with S&H included. Got it home, got it hooked up, wrote a sketch to look at the data stream.   So may have to do some data sampling. Writing some procedures to do some data logging. I will find out tomorrow evening if they are worth the time it took to write them.

Video Clip of Leo

Leo's Maiden Run. Here's the link as promised. After he rounded the corner he got stuck in one. Time to work on sensors and upping his battery supply.  I may go ahead and put a low voltage sensor on his battery packs, so that I know when he's running low or just stuck.

Leo's First Run

Well, he lucked out on his first run, only found half of the corners and got stuck in every one of them *chuckles*. Otherwise, it was a great and informative maiden run. Especially, considering that the only sensors he has right now are his bumper switches. The next project will be to adding some range finders to him so he can hopefully avoid obstacles altogether. Though adding another 7805 FET would probably be a good idea if I want to add some juice to his motors. I need to get more rechargeable batteries as well, it seems that most of mine are dead and I do mean dead as in won't take a charge dead.

I'll try to upload the video of Leo's first run tomorrow. The lighting is bad and there is no sound, but it's a cool video still.

Leo has front bumpers now

Well, couldn't find the small hinges I needed for the bumpers, so I had to improvise. Seems that soda cans are useful for makeshift parts. I'd joked about using one for the hinges, but didn't think I was going to have to resort to such. Working on the rear bumper now and hopefully will get it done tonight so that I can do some more coding. Hopefully, tomorrow can work on the range finders. I need one more for the rear, but all is good.

Yay!

Leo now has front bumper switches! Now just need to attach the bumpers and work on the rear bumper. I've even got the bumpers coded. I did check mouser.com for the bipolar hall effect sensors, and they don't keep them in stock. So, I'll have to scrounge ebay for them, yippee. After I get the bumpers completed, I will start on the IR rangers. That should keep me busy till the hall effect sensors come in.

Working on bumpers and redoing the design

Well got the rocker switches for the bumpers. Just need to put a few pull down resistors, screw them in and attach the bumpers. I did find a Mesmic 2125 accelerometer at Radio Shack for $32.99 plus tax, but found a 3 axis one at adafruit.com for $20 plus S&H. The latter is out of stock though and has been for a couple of weeks now.

I did order the magnets for the tachometer part of Leo today as well. Using 1/4" rare earth magnets on the front wheels coupled with analog hall effect sensors. Will probably order them this week or find them on ebay.

Just need to mount the switches and redo the bumpers on Leo. I was thinking about putting the IR ranging sensors in the drive part of the body, but starting to run out of room in there with batteries, switches, the drive board and still need to put another or change out the battery packs altogether. A few different options, especially if I make Leo an autonomous being and therefore able to charge himself when he needs to. That is sometime down the road.

The drive unit will be using up 7 out of 11(I don't count the tx and rx pins) digital I/O pins and 5 analog pins. I have 3 clones that I bought from Dale and need to build them up, but need to get a lot more familiar with the arduino I already have.

Well off to do something, even if it's wrong!