Friday Night Robotics – RGB LEDs

Posted by Erin, the RobotGrrl on Saturday, August 8th, 2009

A few weeks ago, I added four RGB LEDs inside of ping-pong balls to MANOI’s head. The goal of this is to let MANOI express some colour. From colour, we gain meaning. The meaning we usually tie to colour is emotions! (and food, haha)

I also plan to give MANOI ears, so when they move in a certain way, we can tie emotions to their meaning.

In any case, controlling RGB LEDs is fun. In one LED you have four leads for red, green, blue and ground. This means a whopping 16 leads in my scenario! :O

What I did to organize this was I used 5 24″ servo extension cable, and 1 12″ cable. The 12″ and one of the 24″ are for ground, and the 4 others are for the RGB leads. Eventually I’ll combine all of the grounds together.

Since the Sanguino only has 6 PWM ports, two of the RGB LEDs have to be combined together. Later on, when I get shift out PWM chips, this will be a different story

So I coded in lots of funky functions, there is just one last function that I have to make… I want to be able to fade LEDs at the same time from different starting points to different ending points. I’m sure if I take the brightness value (which is 255), and map it to 100, I can come up with a math function that will let me do that. It will probably have something to do with jumping numbers and mod. I’m going to be thinking about that tomorrow It is a pretty easy problem to solve

Mounting the gyro was fun. I actually started this around the beginning of the week, but I got delayed a few days because I ran out of velcro… so I bought more velcro, and I added it to a stable DOF attached to the torso of MANOI.

The point of the gyro is that it measures movement. It doesn’t measure where you are relative to where it was. I actually got stumbled up with that at the beginning.

Though, in order to use the gyro effectively, MANOI has to be able to WALK! I spent sooooo much time this week trying to make MANOI walk, again. I’m no closer to the goal than I was ages ago. I think it will involve lots of patience and trial & error…

I’m still trying to think of the best way to make MANOI walk. Until I figure it out, I’ll be working on the extras I want to add in some sensors for the RGB LEDs, specifically an IR and an accelerometer. If MANOI is moving with nothing in front, the LEDs will behave differently than if MANOI is not moving with/without someone in front. ^_^

Posted in: MANOI, Programming, Projects, Robot.

Shuffling Robot

Posted by Erin, the RobotGrrl on Wednesday, October 29th, 2008

Instead of having my humanoid completely lift its foot off the ground, it “shuffles”. At least one part of the foot remains in contact with the ground. (It does work when there is no ground underneath the foot, though)

I finished the right leg on Tuesday… I worked on the left one today, and will hopefully finish it off tomorrow so I can spend some time on it on Saturday (and make an insightful blog post for once)

What I’m interested in seeing is what is the maximum speed the robot can go at, without tipping over. Since I’m coding it in slow-motion, I may not account for all of the possible moving parts when the robot is going faster.

Robot motion is pretty cool stuff- it looks easy, but it really isn’t

I’ve also been working on a few other things… More on that (hopefully) tomorrow or Hallowe’en.

Posted in: MANOI, Projects, Robot.

Humanoid Walk

Posted by Erin, the RobotGrrl on Saturday, October 25th, 2008

This entire week I have been working on MANOI! (and iPhone apps)
I discarded the idea of having a separate TX line- as the SoftwareSerial stuff never worked properly. :/

Right now I’m in the process of mapping out a way for the humanoid to walk. It’s intensely difficult… So, I’m doing it with pencil and paper… then I’ll code it into the Arduino, and find a protractor to double check all the angles.

(Hey- my plan sounds FANTASTIC in theory! I guess this will mean I will end up doing everything BUT the plan =D )

I’ll probably make a back-dated blog post on Wednesday as that is when I got the robot to balanced, and it’s a pretty significant milestone ^_^

My “jello world” iPhone app is coming along nicely. I like it a lot, hopefully I’ll be putting it up in the App Store in the middle of next week =D

Posted in: MANOI, Programming, Projects, Robot.