It has been almost six weeks since I started flying quadcopters (see early results here: ). There’s a lot I learned so far:
* it’s physics baby! bringing the controller stick back does not slow down/stop the machine – it changes the force generated by propellers, so the quadcoper will keep moving for a while and ultimately it will accelerate.
* using cheaper and smaller quadcoper helps. Risking crashing $500 isn’t a nice feeling. Nor it the feeling that you can hurt someone.
* flying quadcopters is harder than driving cars.
* it’s worth joining a club – for guidance and insurance
* buying a lot of spare parts make the flying more interesting. Having 4 batteries gives you enough time to have some fun and having spare propellers mitigate the fear of crashing
* it’s addictive, it’s fun
* you will crash
I highly recommend a Hubsan X4. It’s relatively easy to fly and very durable. Mine has survived tens of crashes and other abuse. The set of propellers costs 1.5 GBP and you can get spare batteries for around 3GBP. And it looks really nice ;)
I’m using Raspberry Pi as a media center using raspmbc, which is amazing for streaming (bbc iplayer, 4od) and playing files from NAS and USB. For DVDs I still needed to connect my laptop to TV, which is just an unnecessary effort. Being geek I knew I have to enable RPi to play my DVDs.
First thing I discovered about RPi as DVD is that it let’s you skip all anti-piracy warnings!:
People say it will also ignore region protection (quite useful for my collection of dvds I bought in US)!
So what did I need?
* External DVD (I have actually bought a blu-ray external drive from ebay for 15.89GBP + 2.99P&P, which will work with my macbook air as well).
* Powered USB hub. Raspberry Pi won’t provide the drive with enough power. I’m actually connecting the DVD directly to RPi and using the hub to supply power only. It seems RPi can be powered from the same hub via normal USB connection, which eliminates a need for second power supply.
* A bit of the software:
** MPEG2 Licence – 2.4GBP from rasberrypi.org
** DVD plugin for XMBC (OOTB support doesn’t work good enough yet): http://forum.xbmc.org/showthread.php?tid=158896
ps. when you buy stuff from ebay please check if the seller is paying taxes in your country (eg. is company registered in your country). If not, find another one even if you cost you a pound more. Thanks!
I was thinking about how normal people grow up of student-like stench at their homes and start to live in sterile places. I started to feel slightly ashamed of my place and then I thought – no! This is how I like it, this is how I’m effective, this is what I want! This is me!
This weekend I decided to work on my soldering skills and finally assemble the PWM driver PCA9685 I bought from Adafruit couple weeks back. Not all solder points looks perfect, but I’ve manage not to burn the PCB which I consider a major success. I thank all the
guys how put soldering tutorials on the youtube!
Then I played with software.
* I2C: I used python to steer servo controller via I2C interface. For some reason the Raspbian image has I2C kernel module disabled, so I had to comment blacklist i2c-bcm2708 in /etc/modprobe.d/raspi-blacklist.conf and the add i2c-dev and i2c-bcm2708 to /etc/modprobe to enable them to start.
* GPIO: Raspbian has all libraries loaded by default for GPIO development in python. I had encountered hardware problem instead – there’re many sources on the web describing pin layout of GPIO port, but non of them says which pin is the physical pin 1! I have some gaps in basic knowledge, so I have missed a small rectangle marking P1 – it’s the one nearest to the side of the board in bottom row. See a picture with pins P3, P5, P9, P10 and P11 connected:
Since google is charging for their translate service and bing translator is crap, I decided to switch to Wiktionary. I downloaded main dump marked “en” only to discover, that it contains a bit more than just English. Below is the list of languages with their corresponding word count. Are all of those languages real?