Wednesday, October 9, 2013

I Want My Robot to Carry Groceries

I've moved quite ahead with the old Jazzy Power Chair base with a simple H-Bridge driven by an even simpler picAxe 20M2 to provide the basic elements of a Robot Base with it's own built-in smarts, helping it avoid obstacles.


Check it out on CwhatIcanDo website...

Enjoy the video, read over the how-to and see a crashed robot reconstructed before your eyes.

Monday, June 3, 2013

Introduction to the Mighty Pong)))

Yeah I copped the name as a variation on arguably the most popular, definitely the most famous Ultrasonic Range Finder in the industry.

Yes, we are snapping up the Five Buck SR04's like crazy now.  Here's the problem:  Neither the HC04's or even the famous Ping((( ultrasonic rangers actually hold up very well in rugged applications.  And I'm including working outdoors especially if there is weather.

To that end, as mentioned the other day, I'm building in the lab.  Building out an ultrasonic range finder for obstacle avoidance.


So the fun begins.  You can follow the project on CwhatIcanDo.com.   In fact the URL is http://www.cwhaticando.com/view/?t=Pong)))))%20&itemParent=347 Enjoy.  Have fun!


Monday, June 4, 2012

Arduino VS picAxe

I'm warming up to Arduino.  Not a big Atmel fan.  I like PICs, but PICs require a decent programmer and you are stuck buying a compiler when there are so many available open source.  You have to dig around to get started with PICs at a low-cost.    Enter the picAxe.

If you are a newbie to robots, the picAxe may be the ultimate "learn robots" chip.  You are less concerned with the software, and because PICs are nicely designed you can even not worry so much about the hardware either.


Once you are a "learned individual" you will be ready for a big project in robotics.  If your software is fancy at that point, you probably want to go with the Arduino, since somebody made a processing library, and that means pretty pictures on a PC controlling your robot.  And the controlling will come along later.


So:  
 I created a benchmark test:  Blink Ten LED`s in sequence. Easy peasy with picAxe dev board. Not so easy to get ten grounds from an Uno. Not without either buying a pins-in breadboard for your Uno, or soldering iron and breadboard shield, but the soldering messes up the apples vs apples tests.

The Arduino Uno and a proto sketch is a pretty nice way to make robots and do fun things with controllers and moveable "stuff".   

And...  The picAxe chip, with its built-in BASIC interpreter and host of robotics-appropriate commands like SERVOPOS, and TUNE (plays music or beeps and blurps), as well as the PWMout commands and other general goodies that make LEARNING about robots easy and run.

 The real "competition" if you care to call it that, is between the chips themselves. This boils down to PIC chips against Atmel chips. PIC chips generally speaking require a more technical approach and special programming tools. The compilers are not often simply free, so the investment is larger.

 

Check out the whole project at C What I Can Do

Then get crackin' on learning about and building your own robots!

Friday, March 23, 2012

WheelChair Tours By Autonomous Wheelchair

This project is the end all, collect 'em together project.

This wheelchair operates manually by operating the joystick.
OR
This wheelchair operates by remote radio control.
OR
This wheelchair operates all by itself.

It's true, you can see in the video, me being driven by the wheelchair, along with videos of the wheelchair driving around, without a driver!


You can visit the whole project on CwhatIcanDo.com...  I thought about titling it: Phantom Wheelchair goes without a driver, but maybe not?


Thursday, March 8, 2012

Have some fun with this: Autonomy for a robot built from a power wheelchair! RF control for the same: Original Tests of the wheelchair as a robot! Simple Hello World for Robots, forward, reverse, left, right and so on...

Wednesday, September 14, 2011

5X7 Matrix Driven By picAxe 18m2

It started as a simple way to communicate with a robot.  I wanted my robots to have faces...  I could have one that showed a grumpy face when it got stuck, or when batteries got too low, or just to have a fun looking little "bot" of some kind or another.


Of course, all this tinkering around with lights led me to a LED Matrix display I had lying around the junk box.  I got a couple of them for a dollar a few months(/years) ago, just cause I thought they would make good indicators for experimenting with robots.

There I sat staring at the new picAxe 18M2's that I got when I blew my 18X and wanted to keep experimenting.   The M2 versions of picAxe are "real" chips.  That means, they have enough memory to do some more interesting things with.  And there is the whole faster bus thing, and extra timers, and all that.  The chip is designed to run four (4) processes simultaneously.  Sort of a stubby propellor (8 processors) of course, you have to use different and interesting design processes.   The point is, when you run it in "normal" mode, not multi processing, you can really crank up the processor's operating frequency.

So now I am eyeballing the 5X7 dot matrix display with an idea in mind to using the 18M2 at 32mHz (instead of 4) so I can actually handle the timing of Rows and Columns in the 2057 LED arrays.  Oh boy, this looked like fun.  I could build a 5X7 unit for just over the price of the 18M2 because of the surplus 2057's.   I would let the drivers in the chip supply plus voltage so I could use the same chip to sink (20ma per pin on the chip - plenty for the 2057.

Now I know, I could have gotten the 20M2 (20 pins) and had enough pins to drive the 5X7 display with extra pins to drive more than one 2057 displays.  Like having only one display with a 20M2 on it while having more displays simple wired to the chip.

Things I learned:
  • Average current drain is low when you are switching the power by sequentially enabling the Column lines.  The whole 5X7 array averages well below 20ma probably over time roughly 15ma, even though you are driving 35 LEDs in various configurations of on's and off's.
  • Flickering becomes an issue at low speeds, some the videos are using 4mHz speeds, so you can see the flicker.  Since I switched to running at 32mHz, each pattern looks nearly flicker free.   That could be improved too.
  • PicAxe's just got better for home hacker/experimenters.
  • 20M2's can be had for less than four bucks!  More pins!  I'm switching! (I know, the socket costs more and all that, but it's pennies for the total parts costs.
How to build your own:
  • Of course, the whole build it yourself project with the schematics and some "get started" software are online at CwhatIcanDo.com
  • Go follow the guidelines and build one of these to put into something practical...


Wednesday, April 27, 2011

Weekend Project: Get Started With Robots

Well, it was time for a lot of cleanup. Google videos transferred to You Tube. I discovered early development videos as I attempted to get the dogbot to find the opening to a door, to running the bottom of a little $4 junkbot I picked up used.

It makes for a mighty interesting thing, the flat robot running around the room, seemingly headless.


This in turn reminded me of the handiest tool in my robot workbench. It's a motor driver board with an IR detector attached. Sometimes, I just hand wire it to an old robot or RC car chassis, adjust some software, and I can test about any platform available.

Simple yet handy tool. If you have a servo tester, then you are playing at the level that could use this subassembly.

Why the picAxe? Cheapest and quickest way to get going. That's about all.

Later, I'll do something with some of the other chips. It's not that I don't like programming in C...

Tuesday, December 14, 2010

picAxe 18m2 Robots Look Out!

Bot builders look out!

Yes, it's controlled by simple BASIC programs, but holy moly! Someone took all the complaints I had about trying to use picAxes for anything but single solutions and "fixed" the picAxe 18m2 chip! I bought one from SparkFun for Five Bucks.

It goes beyond the otherwise fun 18x. It all started when I tried to get my little black box robot to do a little more than just run around avoiding objects. Yes, the bot is cool, and the 14m is a great little chip to run it around, but that's about it. I really wanted to be able to read the adc coming from the IR Distance measuring device, but about all I could do was make the bot run around and do some intelligent avoidance. I needed more program space!

So I decided to go back to the old 18x chip I had used in the original 1st robot, the dogBot. It had enough program space to have interesting behaviors, but had problems because the timers couldn't run at the same time. So drive the wheels with a pwm signal, but you'd have to turn off PWM, to get the servos to operate. It was cool, but even with the program space, I could only get bursty operation: See this video, you'll get the picture:



So the dog would pull itself forward, shut off the pwm, then pull forward again.

Originally, I was trying to run the thing off a 14m, but the issue was the timers, not the chip itself. Eventually, it could find the door and do simple things. But it wasn't the greatest.




Now I'm looking forward to using the 18m2 to make dogBot come back to life, though I may change it's form (like giving it two-wheel drive and steering?) It will do things different.

By experimenting with a small platform, I was able to run four programs at the same time. Now I don't have to jerk and hack the PWM and Servos, but can run all at once and give a smoother operation. Basically, I've told the platform to constantly read the distance from the object it is to avoid.

This is not much of a video, but it shows the platform slow down and stop, then back up and turn, then it just shuts off and waits till I press what used to be the reset switch and it starts out fast, slows when an object gets close and stops reverses and makes a siren sound. Once it backs out of the way of the object, it constantly beeps (showing me it is in slow down mode). Right now it can't just drive away, but it's only a test platform, not ready for prime-time.




But here's what happens so far... It's pretty nice, a lot better than run and look and run and look some more. I think the picAxe 16m2 is gonna make my life a lot more easy and things are gonna be more fun than work with the multi-processing in the m2 chip. I here it still has EEPROM bugs, but I haven't needed the extra program memory in any of my simple bots. Maybe I'll like the chip so much... Well, who knows?

Monday, March 15, 2010

Yet another Cheap Robot

Lately I've been reading about Arduino's controlling the ever faithful Rumble Bots. They don't fight any more, they just run around under autonomous control.

Bot Bodies - Rumble Bot


In the early days (last year?) I was playing around with wheels and gears and all sorts of things when I stumbled upon an old Rumble Bot. I had to look 'em up because they weren't selling new ones... They have a card reader built in and all kinds of things that would make them a fun Robot.

I was just concentrating on using the body for batteries motors and gears when I saw Deans article via Make magazine. Dean used Arduino, I had used picAxe. When I added up the costs, I discovered Deans Arduino powered unit cost more than mine, so I thought I'd dig out the old videos and put this thing up as a proper project. So here it is on the CwhatIcanDo website complete with videos and step by step overview so you can build one too...

Dean's arduino cost $30
His Ping unit costs $30

Doing the same thing but replacing even the Motherboard means:
08m (if you want to be fancy) $4
08 motor controller board $15
Sharp IR detector unit $15

You can use the upper part of the body like Dean. One cool thing, Dean put touch feelers in the arms of his last conversion, it's a great idea. Use the rear switch already mounted on most models for detecting objects when backing up too!

CwhatIcanDo Projects

Wednesday, December 2, 2009

Motorola Droid - They Call it a Robot

Got my hands on a new Droid from Motorola. This is the finest piece of gear from moto in a long time. (Since they layed off many software developers.) I'm pretty sure it was google's guys who put the kitchen sink in Android, the Moto and Verizon took the Android, slapped in into a very decent piece of hardware and Voila!!!

Details can be found on C What I Can Do website. Follow this link to Motorola Droid: Article >>

You've got yourself quite a little handheld computer in the Droid. And I did a writeup on CwhatIcanDo Projects. I did a little javascript based script that runs in a browser on the iphone or the droid, doesn't matter. I didn't ask the droid to ignore the screen commands, so it actually jumps around a little, but hey, it works! At least enough to tell me it is possible to control things through a web server on the phone's browser. It works.


So what am I thinking here? Is Droid possibly a brain for robot control? I don't know yet, it may not be fast enough, but the I/O port should be able to talk to a robot motor controller via serial bus.
From Motorola Droid


The big question is can you use the GPS, and all the goodies in there to actually put the Droid into the Robot and allow Bot Control via DROID. Sounds like it would make a good commercial, a little droid with some wheels to get it around...
From Motorola Droid