New Contributor!
Hi! This is my first post as a contributor of the NXT STEP blog.
I have had Mindstorms sets for about one and a half years now. My first was a RIS 2.0 kit. I liked Mindstorms so much that I bought another second handed RIS1.5 kit. And in January this year, I couldn’t resist buying the NXT set…
The robots I have built with these kits can be found here. Also, together with the people from the official Lego message boards, I launched a website featuring building instructions for NXT robots.
As some of you may have noticed, I am fascinated by LEGO brick sorting robots. I have built three of them so far. As you are reading this, number four is under construction…
The first and second used the RCX, the third was made of the NXT kit. The fourth will use both NXT and RCX.
This machine should sort 10 kinds of bricks. (5 colours and 2 sizes) To ‘see colour’, it uses a photocell and the LEGO lamp. This way the NXT is able to see the difference between black, gray, white, red, yellow, green and blue. This is impossible for the NXT light sensor.
When the folder is public, you can find some pictures via my Brickshelf.
I hope to provide some useful posts to this blog!
I have had Mindstorms sets for about one and a half years now. My first was a RIS 2.0 kit. I liked Mindstorms so much that I bought another second handed RIS1.5 kit. And in January this year, I couldn’t resist buying the NXT set…
The robots I have built with these kits can be found here. Also, together with the people from the official Lego message boards, I launched a website featuring building instructions for NXT robots.
As some of you may have noticed, I am fascinated by LEGO brick sorting robots. I have built three of them so far. As you are reading this, number four is under construction…
The first and second used the RCX, the third was made of the NXT kit. The fourth will use both NXT and RCX.
This machine should sort 10 kinds of bricks. (5 colours and 2 sizes) To ‘see colour’, it uses a photocell and the LEGO lamp. This way the NXT is able to see the difference between black, gray, white, red, yellow, green and blue. This is impossible for the NXT light sensor.
When the folder is public, you can find some pictures via my Brickshelf.
I hope to provide some useful posts to this blog!
Comments
We built your Brick Sorter and it works!
We made a video of it that we can send you sometime.
Rick
Welcome aboard!
Rick,
Just wondering, but who's "we"?
Richard
I have yet to build a brick-sorter. Maybe before the summer is out.
Welcome to the blog! I am a fan of your Chimney Climber NXT. Very novel.
Kirk
Looks like you've got some fans... welcome and hope to see more of your designs as well as your commentary and posts.
Jim
"We" is myself and my wife, Fay, a contributor to this blog.
I was the primary builder for Lauren's Brick Sorter. But Fay builds and designs 99.99% of the robots at our house. (She troubleshoots the other 00.01%).
Rick
-Jonathan
Laurens
P.S.
I am Dutch and my English is not perfect. I hope you don't mind if I make mistakes in my future posts.
Chris
Nice to see another European contributor to the blog finally. :-)
Matthias
I used this phototransistor because I didn't have any LDR's.
These phototransistors are also used in the LEGO light sensors by the way.
The resistance or 'raw value' varies due to the amount of light.
White or yellow bricks give a raw value below 60, while black bricks result in a value of 950. (Measured while using the LEGO lamp at 9 volts)
The difference between blue and green is about 200, this difference is a lot smaller when the NXT light sensor is used.
Another advantage of this method is the possibility to control the intensity of the lamp. The NXT can't see the difference between yellow and white when the lamp is at full power. When the lamp is at 60 % power, there is a clear difference: A white brick results in a raw value of about 170, while the yellow brick results in a value of 270.
Anyway, to make a long story short: This method allows you to see the difference between some colours, the NXT light sensor can’t see this difference.
I hope this made sense. :-)
Laurens