Diagnostics Program

This is a small program that runs on the NXT. Its very simple, but is meant to be helpful. You will probably need LV 7.1  and the toolkit and th drivers in the least to put this onto the NXT.

Will upload diagnostics.rxe version for easy download, but you will need good job.rso on-board.

http://www.mediafire.com/?do4di7i6a2t62 Link to file folder.

Hope this helps for those who need it, or just for a fun mini-project. Tell me what you think. Post comments with ideas…, links to new files too…


Problems and inspiration.

Today I went to a FRC. It was fun, and I joined a team only 3 weeks earlier, and hopefully things will turn out good. So far they want me to be their lead programmer, and it sounds like fun. Today’s match was a ton of fun and it is a great place to meet people that love robotics. I think these robots are more fun than your typical robotics, and it beats the FLL by 100 times better. These robots make your Lego NXT sets look like toys [well, lego’s are toys aren’t they?]

They seem to have a lot of fun and it included having the best food I’ve had at a robotics event – a group was fundraising for their robotics team and was selling these great burgers that were amazing [partially because they were cooked on a propane stove] and it was just a fun experience.


On the bad side, I found out that port A on my newer NXT no longer works – the motor output is fried. The rotation sensor seems to work OK though… Probaly something I should report to Lego.

I could probably take it apart and find the problem, but there’s no point. I’m probably better off making it into a full rotation port and build a rotation sensor so that I can do it without a huge motor. I looked up the specs, and it’s a simple trigger system

1 degree equals this en-emulated into the two signal wires:

0 0

0 1

1 1

1 0

And opposite order for the other direction.

I tried making one with light resistors, but I can’t get it to work. Probably better off using them as light sensors. I feel that light sensors reflecting off an object is more accurate at telling distance than the Ultrasonic, which works best in port 4 than any other [partially by the raised transfer speed/communication]

I’m thinking I’ll work some more on the printer.. make a skid steer out of the other robot for now, at least it only takes 2 motors, and I could use the prototype board to make a third motor port…


There were a lot of cool ideas at the FRC and am considering what to build out of the ideas I saw there,n I could really improve my robot with their ideas.

Printer update! Surprise Enclosed!

OK. So a friend of mine and I got together last weekend and we totally rebuilt the printer. It’s design is very similar, and I’m sure we used many the same parts, but now we have a more functional robot. While it is practically impossible to get it to feed paper into it correctly, we finally got it to work. We gave up dots and complex programs and it paid off. We can draw lines on the paper now instead of lousy dots that the stupid ink-jets that take three hours to print. We can only draw one line at a time, but it works much nicer. Found the camera so pics to follow.

Other project:

Centrifugal Force Air Compressor:

This is a cool project. I was actually trying to make my own GluideWheel or whatever it’s called to connect PF motors as if they were NXT servos with all the rotation sensor stuff. A great idea, but I wanted to build one first, since I have the equip.

Really its not that hard to make a lego NXT motor port rotation sensor. All it is is a group of LED’s and light reactive switches [whatever you call those useful things] and a correct hookup. I hooked up the PF to a NXT port and found that the 2 amps out of the NXT was much better than the 200mA of the battery box, and decided that this motor is practically unstoppable, which when connected to a NXT port, it’s practically that. So I decided to gain centrifugal force and use it to run an air pump geared up from the normal motor, and it worked fine, in fact it went all the way to 47 PSI before it couldn’t kep up with the leaks, and just stayed even. But under the regular battery box hooked up the way it is it would stop at about 10 PSI, hardly enough to move a small piston.

This was a great idea that works amazingly. More tomorrow.

I cannot seem to find my camera, but i have built a walking robot [well, it has front  legs and back wheels, but the legs are what make it go forward, or backwards. It works OK, but i’m sure with a better leg design it would walk more efficiently.

This robot is kinda inefficient, as it takes 2 steps forward and one step back. But it still travels, works better on solid smooth surfaces than, say a rug. It works really well on my mouse pad, which is soft foam with a layer of cloth on top, all a solid piece.  The robot is actually very simple and most of it can be made just by looking at a side view since all the mechanics are on the outside for looks.

It does walk very slowly though, maybe an inch every 3-5 seconds, depending upon the surface.

Pictures to follow if I can find my camera. I took apart the solar panel idea. It worked, but I found that the solar panel charged the battery the first day, and it didn’t really need charging for the next week with the LED output of only 4 led’s…

Program for the solar panel hookup to the NXT and a full schematic will be around soon…