Wow, What A Weekend!

I only hope that you had a spectacular weekend like I just did. I had the opportunity to spend many hours building over this long three day weekend. I worked on four different projects with great success. And since I took MARVIN apart, I had tons of parts to work with.  Man, it's good to be building again.

The first project I worked on was an updated Stewart Platform. Not much different from the last one I built, but this is far more stable in all positions. I changed one of the joints and moved some of the Linear Actuators in toward the center. I didn’t take any video of it because it operates pretty much the same as the last version. But take my word for it, it is better.

The second project I worked on is an updated Lego Flexpicker. I have some ideas that I might want to try. This version uses about half the parts, is lighter and more compact but not smaller (if that makes sense), and much easier to mount. I have been throwing around the idea of building more than one to see if I could create a large pick and place system. More info to come.

The third project was more of learning experience for me. I wondered if I could make the motor speeds follow a complex function, such as a trigonometric function like sine or cosine. I was able to do this without much hassle. What this means to the non-Math nerds such as myself is that the motor speeds up and slows down, reverses and does the same. It would remind you of a pendulum.

And I have video for the fourth project. A few months ago here on Tinkernology I blogged about the Lego Education Mobile R/C Robot called Rooster. I spend about a day building myself one and I named it The Hen.

It is easy to control. In fact my five year old likes to drive it around, but she doesn’t quite have the arm movements down just yet. This project has a high “playability” aspect, almost as much as the Lego Bulldozer does. I would recommend this project to anybody who likes to play as much as build.

My favorite part about this build is the gripper. I have probably built forty versions of grippers over twenty years or so; I am just fascinated by grippers for some reason. But this one is special. I have built this version as shown a half dozen times because it works so well. I use a M PF motor running a clutch gear to control it. When the gripper is fully closed or open, the clutch slips so there is no stress put on the motor.

Now I can’t wait for the next three day weekend.

Lego NXT GrabBot

A few days ago I posted about a Lego Education R/C robot called Rooster.  Over on YouTube.com, watchfuleye1000 has created a pretty similar robot called "Lego NXT GrabBot" and did a pretty good job of it too.  Although I am not exactly sure what all the linkages do, but it works great.

Rooster

I was checking over my fresh copy of the Lego Education catalog I got in the mail yesterday and I noticed a couple of pretty cool robotic arms. Normally, I just glance over them mainly because they are super expensive and why buy one when I could build one. The big one called Brutus is $3500 and pretty detailed and would be fun to play with, but more fun to build.

Then I noticed the smaller one called Rooster. Rooster isn’t really a robotic arm, but an R/C arm. I took a glance at it and it looks like it can be fairly easily made using five PF motors; two driving motors, one arm lifting motor, one gripper tilting motor and one gripper motor. You could really get lots of bang for the buck. And of course, you could throw a NXT and some servos and some sensors in it to make it programmable.

I think that a PF project like this has some serious “playability.” Imagine chasing the kids and the cat around the house with something like that? I might even let my four year old play with it. This guy is certainly going into my “Will Build” project list.