Let's Make Robots!

doubts regarding circuit protection fuses

So, overall I know what a circuit protection fuse is and what it's purpose. I also know that are several types of fuses, in many shapes and forms, one-time-only and resettable (self, or non-self), slow and fast acting and some of rules of thumb for when using one or the other. However, my personal experience is only limited to often trigger the circuit breakers of my mains power supply (by either drawing to much current or shorting stuff [as a kid *cough* long time ago]) and blowing a few glass fuses.

Soldering station -- bad station, bad tips, bad user... or all of them?

Well, I have a Fixpoint AP2 soldering station... it's basically a cheap soldering iron with a knob to control (or try to) temperature. I recognise that my soldering skills are nothing to write home about (I had no previous experience). Despite that the solder tip that came original with the soldering iron (despite being a bit "thick") I think would behave normally/properly so any soldering mistake I could only blame myself. Then I decided to use it to poke holes in plastic (and yes, I knew I would ruin it). Which led me to buy a set of 4 tips.

[SOLVED] toggle ON/OFF remote LEDs

I can't believe I'm just about to ask this... but it has been a nasty weekend and despite all I've managed some progress. So yeah, now a feel a little silly at throwing the towel at some LED toggling.

So, I have a prototyped remote (TX) that send X, Y info from a joystick plus four buttons. The information is transmitted as an array in the shape of:

[XXX, YYY, A, B, C, D]

feasibility of DIY wireless headphone kit

So, I was searching the market for what my wireless headphone options were and got quite disappointed.

As it seems, wireless used is either IR, RF (on the FM/UHF band) and Bluetooth (also 2.4Ghz seemingly working in the router's norm).

IR ... needs line of sight, small range...
RF... prone to interferences
Bluetooth... small range
2.4GHz... some reviews said they interfered with the home wireless routers


Smart trashbin

Well, I only took a quick peek but this bot sure looks nifty. And if my assumption that the kinect is used as a sensor for the implied autonomous part of the project and it's not some guy off-camera controlling the trashbin then it's even niftier. (I'm too lazy to do any further verification :P)

Interrupts and wheel encoding... a beef with...

EDIT (June, 25th 2012):

The headache just doesn't go away...

Despite the photo below now I have a tube of black heatshrink shielding the sensor. It increase the analog output, for both cases (black and white). Regardless, the behaviour remains the same as without the shield when I move unto digital pins. I've been trying to deal with debouncing for the past couple of days with no luck.

// Playing with encoder digital readings


const int sensorPin = 7;


int lastColor;

int currentColor;

int count;

Comming to grips with arduino, bootloaders & ISP...

UPDATE/ADD-ON: June, 6th 2012


For the sake of argument, let's pretend I'm a bit thick in the head and also that every day is a Monday for me.

Being a bit reckless in some respects, and hating the shipping wait times, I've ended up ordering a few ATmega324 chips, so the current Atmega328P-PU tally is:

- 1 blank

- 1 w/ the duemilanove bootloader (supposedly, but I believe it so)

- 2 w/ the uno bootloader (which I have some heavily suspect might be blanks or w/ the duemilanove bootloader instead)

Piezo elements and their Resonant Frequency

Ok, I was looking forward to stock up on piezos. Not particular plan in mind at the moment, but I just want to have them around when I need them. (shipping times are bothersome) So, I was looking for me most versatile ones.

Then, I've realized that I know next to nothing about piezos, but when looking around on ebay, what it seemed to vary was the size of them alonside with the resonant frequency.

So looking for resonant frequency of the piezos I've found:


[ALMOST SOLVED] HC-SR04 still giving me grief...

June, 7th 2012


- Updated schema.

- Segregated power supplies of arduino + sensor
- Added 0.047uf caps to the motor leads (one per lead) grounded by the casing.

- Motor + servo power supply changed to 4 AA rechargable batteries.

- Arduino + sensor when powered by USB everything seems to work fine, except the sensor is a bit slow to respond but that surely it's the code's fault.


- Pending issues:  

PanaVise vs Helping Hands

Is a Panavise Jr 201 worth the extra cost over a Helping Hands set?
Any personal experience with both?