Let's Make Robots!

What to do when you have a project idea but don't know where to start

Everyone starts at the same place in the very beginning: You have a great idea but don't know how to do it. What to do?

The first thing you do is probably (should be!) a seach with Google/Bing/whatever. Chances are you will get a bunch of links that have a lot of info that isn't much good to you in the beginning (but later on you might find they were full of gold). This means you need to break down your project into smaller bits.

BoB's and filament

I love the invasion of the BoBs! Like a herd of little boxy Android droids. Although I don't have a 3D printer I was wondering how much filament was used to make one of those guys. More that I was interested in the cost involved as to have a better idea on how much to offer someone to make a BoB for me.

Sorry if it's mentioned in a post somewhere, I didn't see it.

Experience with DFRobot's PCB service?

I've had boards made at seeedstudio and OSHpark and both have pros and cons. I was thinking about dropping my next gerber file load on DFRobot but wanted to see if anyone has used them before.

USB cable/connector preference?

I wanted to ask the population if there is a certain USB connector you prefer to see on your equipment. Maybe it's because you have a thousand cables of that type or maybe you like the form factor. Whatever it is I'd like to hear all thoughts. For those not versed in the different types of USB connectors here's a pic for you:

ST's new STM32F0 Discovery Board

I do believe I have one of these coming to me and wanted to know if any LMRtians have gotten their paws on one yet. ST appears to be trying to bring the cheap 8-bit world and fancy-pants 32-bit worlds closer together with this unit. This board is certainly cheap (~$7.99 I read) or free if you register and request a sample.

Driving an L293 with one I/O pin?

There's the circuit, here's the plan...

I remember the remote control cars from yesteryear (the ones connected to the controller with a wire!). They had a joystick that just went forwards and backwards. When pushed forward the car would drive forward in a straight line. When pushed back, the car would back up while turning. There was no real directional control. I'm trying to acheive a similar level of control with this circuit. The idea is:

How to choose a DC motor for your robot

The question "Which motors do I need?" is a constantly recurring question. I've seen simple answers like, "You need a gear motor" and "Go for a high gear ratio" but these are inadequate for calculations. Given the usual voltages, motor drivers, wheels, and speeds used you can be somewhat general about things but trial and error can be inconvenient and expensive. I thought I'd post this attached .pdf that seems to be a lesson plan from Gear Educational Systems that covers motor selection.

Maxbotix "daisy chaining" question via email

I got this email and I thought it wise to post on here for a couple reasons. One, I would like to have other eyes look over my "advice" lol and two maybe it will help someone in a future search. Anyhow...

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Inter PICAXE serial communications advice? -SOLVED-

Main code summary: The 28X2 raises a pin high, triggering the interrupt on the 08M2. The 28X2 then sends a number (1 to 5) via serial connection to the waiting 08M2. The 08M2 then I2Cs the correct bits to an I/O expander to turn on an LED pattern:

28X2: