Let's Make Robots!

Sharp

Hopefully moves around and scares the cats.....
Using a
My fourth robot and my first quadruped, influenced by Chopsticks Junior and Jeffrey The Quadruped. Built using: Read more

Saying HI again. Still here building bots...

Hello again!

It has been ages since I have been on LMR and I missed you guys something fierce! :-)

I have just built another "generic" Arduino based bot (it WAS NOT fun getting the driver to install in Windows 8!!!)

(I will try and get a picture and more details up when I can, but basically it uses a Arduino Uno, a servo/Sharp rangefinder combo and a L293D bridge chip to control 2 very low power motors driving the wheels in differential form. Like I said, pretty generic.)

Navigate via GPS, Compass, and avoids obstacles using 5 IR sensors
Using a
Hi all, I'm Matt and currently a junior in high school. I built first robot called the "A.S.R.B." over the summer for the Authentic Science Reseach Program and I … Read more
Navigate around via infrared
Using a
MiniBot is a robot I created to test my new nanoDuino boards. It is based in an old Mini Cooper toy car I had. It is a very small car, almost the size of a arduino … Read more
Hellow there LMR i geus i haven't made any robot if i hadn't found this webpage ;) so here i am with my first robot. its a pretty basic idea, but for me ofcource … Read more
    Pictures in High res. now available on: https://picasaweb.google.com/117478617231202648212/Primo?authkey=Gv1sRgCLy4gIfUuZSIrwE The Code is on English now … Read more
Navigate around with IR sensor
Using a
R.A.V. ( Red Avoiding Vehicle) LOG: // 10/2/11 : LMR RAV and servocentercode files added Read more

Lots of strange Sharp IR Noise…?

Hey everyone. So, I just finished my first robot in a few years, my first being 2 1/2 years ago. This one is a lot more complicated in terms of hardware since I made my own boards and all, and have 5 ICs in one circuit. I'm done with programming and everything runs well but there's one ongoing problem with my Sharp IR GP2D120 sensor.

Sharp programing on picaxe

Ok so I want a basic obstacle avoiding program with my sharp sensor. It is made on the start here robot. The programming language is picaxe basic. After hours of trying I still cant get it going correctly. So i hope u can help me. Thanks

The idea- It is supposed to read the distance and then decide whether it is far enough away to proceed forward or to go to sub program ahead (go backword, I know confusing haha sorry). So if you have any ideas please tell me. Better yet revise my program or make a new one and show me it. Thanks! First time with sharp.

main: 

This is the fully functional test chassis for my Arduino based sumo robot. It will be competing in March, 2011. For the prototype I am using a piece of plywood to … Read more
Navigate around via sharp IR
Using a
I got the parts yesterday and i done building it already :) Read more

Filtering Sharp IR sensor's noise on power rail

I have some problems with Sharp GP2D120 IR distance sensor on my next robot, Hammer. Sharp seems to cause noise on the power rail and the noise gets to LM386N-1 audio amplifier making really annoying "ringing" from speaker. Or at least this is what I suspect. Check the embedded video for a sample of that noise (or go here: http://www.youtube.com/watch?v=WIQ0qY6gFpQ). The video starts with Sharp disconnected and then I connect and disconnect it couple of times.

Sharp IR sensor Broken?

For some time now ive been trying to get m sharp ir sensor to work with my arduino.
its all plugged in and fine but no matter what is infront of it the data will keep bouncing around 1000.

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navigare around via sharp ir sensor
Using a
this is a silly thing, had to make my own version of a clasic robot...... using meccano (erector) pieces, Arduino S3V3 single sided board, a pair of servos and a … Read more
navigate around via ir........
Using a
Very simple robot with sharp ir and microswitches.............. 3 servos and arduino brain.......     Read more

What parts to use for the next LMR Start Here robot

As you may have seen in the LMR Live Show, we need a replacement for the Sharp sensor used in the Start HEre kit, as the sensor used till now is no longer being produced.

On http://letsmakerobots.com/node/22657 a lot of really new and interesting sensors came to my attention.

Now, since I am going to do a whole ned version anyway (we cant have instructions with images that doesnt match), I was wondering if there would be other parts that should also come in to the modern times?

Mini Sumo Bot Parts!

Intro

I decided to make a mini sumo robot a few weeks ago instead of doing an obstacle avoider. Turns out that once you think about it, mini sumo bots and obstacle avoiders are pretty much the same! The only changes I would need to make would be to the code. Great! Sumos can also double as line followers. So in short, they're pretty versatile. Here is an image of most of the parts that will go into this sucker. 

Picture

Environment mapping

I'm currently working on an application for mapping the environment with a range sensor. Right now it's only a sharp sensor (GP2D12) mounted on a servo that is turning slowly, while the readings and corresponding servo angles are being sent constantly to my PC via serial. The program then converts the angle and distance to x/y coordinates and draws a map.

What distance sensors are better and best?

I am working on a much faster & stronger version of Robot Wall Racers, using quite fast RC-cars

I want to use lasers as distance sensors, but I think they will be a little over budget, altough this is a paid for job :)

Yes, SRF05's clai, they can detect a broomstick on 3 meters.. but in reality they are not stable before say 1.5 meters.

1.5 meters when you are traveling at 25km/h is NOT a lot, when you even are set up with drifting tyres.

Programming help, sharp IR mounted on servo

Hello

I am trying to control my bot using a sharp IR sensor mounted on hitec servo with arduino mega. The pseudocode i have so far is as follows:

1. Set servo at 90deg and read IR sensor value
2. If val > 200, then stop the bot for a second
  a. Turn servo 0 deg completely and read ir val
  b. if val < 200 then turn bot left
  c. else turn servo 180 deg and read ir val
  d. if val < 200 then turn bot right
  e. else if cant turn right or left, reverse a bit and then turn the bot 180 degree and go straight.

Sharp again - part numbers confuse me

I am shopping for Sharp distance sensors like the one used in "Start Here". My local mail order supplier charges €26 and I am boycotting them for that reason alone.

So I am searching for other suppliers and I find confusing part numbers. I understand the difference between Analogue and Digital sensors. I want the Analogue kind. And I want to measure distances up to 11.8" (30cm).

Are these parts all that different? 

GP2D120
GP2D12
GP2D120XJ00F

sensible discussion on "open collector circuit" for sensor

Just found this on hackaday:

" ... Why open collector?
An open collector output doesn’t toggle between high and ground, it toggles between ground and unconnected. The unconnected state, also called high impedance, exerts nothing on the output and allows the signal line to float.
...
Open collector outputs are useful when several sensors need to share the same microcontroller pin. ..." (my emphasis)

Navigate around via Infrared Rangers
Using a
1-1-09 Roger has been working like this for a while, but I never went around to make a video of it. Here it is. I added some white LED's as head lamps and that is … Read more
8.Dez Hello,   Thats Me: Yes, now i am here. I am from Switzerland (I speak German) and I'm 15 years old. I like all things with Robots, Electronic and … Read more