how everything is connected (for now)

There are currently three different parts:

A "requester" client that will request for a door opening.
A single "target" client (the Raspberry Pi) that will receive requests
A central server that will relay the messages between the "requester" clients and "target" client

The messaging is done using WebSocket--really great stuff.

"Requester" Client
Currently just a simple PHP/JavaScript page that can send a textual message to the central server.

"Target" Client
A Python script that keeps an active WebSocket connection to the central server. As said above, this is executed in the Raspberry Pi.

Central Server
A Python script that listens for WebSocket messages. This uses the Tornado library for Python for creating the WebSocket server. This is executed in the Ubuntu web server.

I'll try to put more details as I go, but for now, I think this 10000-feet view is the better for catching up with the status logging.

Comments

nodejs migration

Having been playing around with NodeJS recently, I (naturally?) started re-writing some of the OpenSesame code using Node last night. I think I've only worked on it around 2 hours so far, but I've already set up a basic client interface (a socket.io chat tutorial rip) with a server that the Raspberry Pi can connect to and receive requests to open the door. This is probably due to socket.io's socket management (socket.io is the WebSocket module for Node); for my first implementation, I had to manually write up a structure that managed sockets, but that is pretty much handled by socket.io. Also, the servo control logic is pretty much recycled (and the Raspberry Pi code is still Python), and I do remember spending some good time figuring that out. Cool neverthelss. I'll probably keep both versions around.

quick recollection on setting things up

If I can swear that the password is correct, then it's possible that I'm getting the ID wrong. Hadn't logged into the web server in a couple of months and was unable to SSH into it. After an hour or so, I ended up deleting the instance and recreating a clean instance (read: erasing everything). I then realized I'd been putting the wrong ID. apt-get install sudo apt-get install Anyways, some links I visited when setting things up (pretty much a dump of whatever I copy-pasted to notes) : Raspberry Pi http://www.makeuseof.com/tag/optimize-the-power-of-your-raspberry-pi-with-raspbian/ Logging http://docs.python.org/2/howto/logging-cookbook.html Tornado - Python webserver that supports Websocket http://stackoverflow.com/questions/2924991/what-popular-webservers-have-support-for-html5-websocket http://lowpowerlab.com/blog/2013/01/17/raspberrypi-websockets-with-python-tornado/ http://stackoverflow.com/questions/11695375/tornado-identify-tra...

how the fingers work

the fingers are moved using wires and tension. each finger is looped through with a wire/string/line in a top-bottom fashion. when the top wire is loosened/bottom wire is tightened, the finger curls in its joints, resulting in a "bent finger". you don't have precise control of each joint movement, but it is simple enough to be controlled by a single actuator (in this case a servo). here is me just using my own hands as an actuator: here it is hooked up to as servo and controlled by a potentiometer: the movement is not smooth because 1) it's controlled by a potentiometer that I am controlling, as seen in the background, and I was unable to move it all the way with one smooth finer motion. 2) the tension in the line was not entirely tight. I need to learn how to tie these well. now I have a get a bunch of servos. much credit and thanks to Inmoov once again.

the quest for robots

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