Let's Make Robots!

Tayda?

Hi,

Anyone have experience (good or bad) with Tayda electronics? Please share.

I just googled this one part and Tayda came up as the absolute winner on price. Who would like to teach me how to order small quantities from suppliers far far away. Any caveats, consumer traps, unusual conditions, broken promises?

Motor Control for 6WD Wild Thumper

Open call for suggestions:

I own a bare 6WD chassis "Wild Thumper" by Dagu, designed by Oddbot. And I have (2) "racing packs". Those are basically 6 NiCd cells in series, providing 7.2 Volts nominally. The motors are rated for 6 V. Stall current is listed as 5.5 A.

Even the most basic speed control will need some sort of amplifier for the PWM signal. Let's start very simple. Just speed control. Just one motor. One direction. What kind of transistor shall I buy? And what kind of circuit shall I use?

January 2010 Release of LMR

Just for the historical records....

New release of LMR January 26, 2010:

  • As always a lot of under the hood-work, regarding spammers and security.
  • New content type: "Something else". So many times people have made something great that was not quite a robot. Now it can be published, see front page, Add content.
  • New exciting components-section - try it out on top menu; Components

As always, 95% of the work was done by Del Rudolph. Thank you for your amazing work!

How do I filter audio?

I just successfully hooked up an electret microphone to my PC, without burning either. I use a very simple circuit to pre-amplify the signal, using a single general purpose transistor (2n3904). The microphone is electrically separated from the amp by a capacitor (.1 uF). The same trick (.01 uF) is used between amp and PC.

Audacity is able to record sound and display levels. I am getting decent range across the audible spectrum.

The Pulse - 2010w07

LMR on the Brain
Sensing the living LMR community since 2008w43.

Flash!

Pulses are sparse and they shoot by in the blink of an eye. Make sure you have your automatic trigger set up and armed. Or you will miss it.

Make over?

Just to explain the changed avatar:

brill_compare.jpg

This replaces my 2003 model. And is improving my sight by leaps and bounds. I really should've had my eyes checked years ago! Before LMR even!

LMR's second year in pictures

What do you know? Memory Lane can be 4000 pixels long. Take a trip and share your memories with the rest of us as they shoot through your brain's déjà vu lobe. Any juicy anecdotes? Horror stories?

Do you recognise these fragments? Can you even tell how many there are? I dare you all to search a few node numbers. Heaven knows I tried and failed (for about 5% of them).

The Pulse - 2010w04

LMR on the Brain
Sensing the living LMR community since 2008w43.

Happy Birthday

All over again

LDR Cyclops - holding, scanning, seeking, recalling

Continuation from here.

Video straight from the camera to Youtube (Sorry Oddbot).

scans.gif

 Continued here.

Slightly more advanced LDR eye

Read this history first, if you have an hour to kill.

The challenge: make your bot rove around your house. Use no active beacons. Use observations by your bot only. Now, does your bot know where it is?

One possible answer: an eye and a brain.

Room Recognition

Each room in the house has a unique lighting situation. A simple eye that looks around in eight directions would "see" a pattern of light and dark segments. Each cell is connected to one ADC on your uC.