Feb 21, 2012

Mini RC Car - Part 4

Back on track with 5v...continuing the Mini RC Car build.

So I couldn't wait on my 3.3v voltage regulator.  I decided to switch the car to 5v and use a good old 9v battery.  This is what it looked like when I tested the new power system:

This has to be the ugliest RC car ever made.

After getting over the look of the beast, I now have to do the following:

  • Test the servo
  • Clean up the electronics (there is still some quick prototyping part or assembly)
  • Make a more permanent stack assembly for the battery, power regulator and circuit board.
  • Programme the Arduino and the Android phone (remote)

This shouldn't be too long.  Here's the car running a test with the new power system:

To view the whole project, go here

Feb 15, 2012

NASA != Marketing (rant)

In case you didn't know NASA is still there.  Thanks to our Russian partners we can still go to the Space Station where there was, today, an amazing display of supper high-tech showmanship from NASA.  A man shook a robot hand.

Yes you read it right.  A man (take the time to let it sink in) shook the hand (I know you think I'm going to say man but wait) of a robot.  Wow.

I'm personally a big fan of space exploration and robotic and I think that Robonaut2 will do great things.  It will at least pave the way for this kind of technology. But seriously NASA, can you make anything look cool for the average Joe?  If you can't picture the moment, here the scenario: Without the camera even moving, two guys (astronaut) float behind the Robot (which is not moving) and, after what seams to be a endless speech,  proceed to shake the hand of the robot who, for that special 3 seconds, moved 8 inches (toward the astronaut knee instead of the hand). There's a thing about good presentation: it's called practice.  Or you can you can do it live if what you're doing is so incredibly amazing that fumbling doesn't matter.

How about rock paper scissors? Even better, how about rock paper scissors lizard Spock?  If an Apollo astronaut would have been  at the control of the robot, I bet he would have done something cool.

Oh Internet, help me compile a list of  'The thing that NASA should have done as the first Robot-Human interaction'. Not a joke list but something that's worth showing the kids, something memorable.  And um... let's  try to stay politically correct please. (Comment here or use the hash tag #rb2firstmove on twitter)

I'll compile the list here:
  •  Rock paper scissors lizard Spock
  •  Thumb War
  •  Brake-dancing robot moves and arms wave
  • (your idea goes here)

Feb 14, 2012

Mini RC Car - Part 3

A few bumps in the road...continuing the Mini RC Car build.

First I decided to get rid of the variable voltage regulator.  It was causing all kinds of problems mostly because I'm using a 3.7v power source.  Anyway the Arduino runs fine for now and I have some 3.3v regulators coming through mail pretty soon.

A glitch never comes alone but I'm lucky since the next problem was simple. The DC motor is creating noise feedbacks that are confusing the servo.  That one is an easy fix by adding a 0.1uf capacitor on the motor.

The third one is a show stopper. Or maybe I should say 'a show slower'.  The cellphone battery I'm using is not strong enough for this whole operation.  It's a 3.7v 850ma LiPo cell.  I have to power the Arduino, the BlueSmirf Bluetooth board, the servo and the DC motor which is done using a transistor.  I guess I should have done some calculations first.

Soooo, I'll get to that and I'll order the right battery.  Until then, PAUSE on this project.   Mmmmm, that gives me an opportunity to start another thing.  Muha ha ha ha ha

To view the whole project, go here

Feb 11, 2012

Mini RC Car - Part 2

...continuing the Mini RC Car build.

To attach the steering servo, I drilled holes in the frame and bolted the two together.

I then hot-glued the front frame to the rear half, making sure I had enough ground clearance and all 4 tires on the ground.

The next step was creating a board that would support the Arduino chip, a socket for the bluetooth breakout board, the 3.3v voltage regulator and a socket for the servo connector.  Here's the prototype:

After a bit of soldering, here what I have so far:

Now that I have all the main components, I'll do the final assembly and start programming the on-board Arduino code and the Android controller app.

To view the whole project, go here

Feb 9, 2012

Mini RC Car - Part 1

While cleaning up the basement, we came up on that old electric racetrack and finally decided to get rid of that thing.  Of course I kept all the electrical circuitry and the kids kept the cars to play with.

Since I needed another project to start to justify not working on all the important stuff, I decide to re-purpose one of those car into a mini RC car that I would control using my Android phone. Communication will be done through bluethooth which I tested earlier.

My first test was to control the motor using an ATtiny13 Micro-controller.  This chip uses the same code as Arduino but has only 8 pins.  I powered the assembly using a LiPo battery from a dead cellphone.

I started by cutting the frame in two and hot glued a micro servo on the front part.

I then used a PC card slot-cover and bended it into a frame that would join the two half.

To view the whole project, go here