The Guiding Propeller

2009-11-04T00:00:00.001-05:00

I have continued my research for a way to compress and convert a video stream on the plane. I remembered reading about something called a Gumstix computer and I decided to research further. I have found that they have an amazing processing ability and one could easily handle controlling the entire plane. In order to keep in the spirit of the project, I will only use the Gumstix computer to handle the video. Wish me luck!

First Post in a While. A Lot has Happened.

2009-09-07T11:36:00.003-04:00

In the past month, I have finalized my main hardware and their schematics. Now that the planning is done, I can start working on designing the PCB. I will upload my "schematics" and other drawings and things I have later this week. For now I'm in Georgia visiting my grandmother.

My current interest(s) are a diy smd solderer such as a hot plate, toaster oven, or electric griddle. I already have a temperature sensor that I could use for a PID loop temperature controller [if anybody has one of the aforementioned heating objects, I would pay for shipping on a donation].

The other thing I have been looking into is a netbook. It would be much easier to use outside for data logging, video feedback, etc., compared to trying to haul out my normal laptop that is a 'family' computer; in other words, if I have this computer tied up, my mom is left hanging. If I got a netbook, it would be a computer I could dedicate to using for the Guiding Propeller and for long term computer projects. Since many netbooks are $500<, it would also be less of an expense if it was KIA.

It Has All Arrived!

2009-08-24T13:48:00.000-04:00

All my new toys have now arrived, and I'm gonna go play with them!

Parts have been ordered! and sampled.

2009-08-16T21:30:00.002-04:00

In this bad picture, you may be able to see that I have ordered my firsts parts.

I bought:

a 555 timer, not for this project, for an old kit I have
a 7.5dc power adapter for my dev board
an IR transmitter kit to play with the programming on the propeller
and the Propeller Professional Development board

All this stuff is supposed to arrive on Monday the 24. I also requested a sample of a temperature sensor, the same one that's $6 on the Parallax site, directly from the manufacturer. I saved $6. I'm not sure when it will arrive.

GPS Board Modifications

2009-08-08T23:13:00.004-04:00

I've done more work on the LEA-5H module pcb. I was looking into what parts will be need for the board, specifically for the Open Circuit Detection circuitry. Many of the parts need are extremely small (some around 1mm sq.), so I have decided to opt out of have the OCD. The benefits it would bring are not worth the effort it would take and the risk it would bring to soldering the board.

!!! I forgot to make a blog post when I finished my ADC break out board. It is now completed and you can find it here. Enjoy, and let me know if I need to change anything.

Intenational Viewers! And gps woes

2009-08-03T21:41:00.003-04:00

I just checked out the Google Analytics report and not only do I have views from America (the main source), but also from West Vancouver, Canada, and Perth, Australia! I'm going global! ;)

Aside from my global popularity, I have run into a 5 foot tall speed bump. I'm working on making my pcb for the LEA-5H gps module from U-Blox, and when reading the hardware integration manual, the difficulty of this step hit me. Everything is so specific and sensitive, making this board is going to be a pain.

I'm currently wanting to have the Open circuit detection and short circuit detection circuitry on the board, as well as a SMA port for this antenna to plug into, and a usb port, and then the I/O to the main Propeller board.

If anybody already has something like this, or wouldn't mind helping in the construction, it would be greatly appreciated if you'd let me know.

P.S: What's the point of all the "holes" on the PCB as seen here, I have seen them on a number of boards and am baffled by them.

**Edit (8/4)**I contacted Peter Miller, over at Petermillerphotos.com, and he told me that the holes are to improve the ground plane of the antenna. He also gave me a few tips on the microstrip and its resistance, he suggests that in order to get the correct 50 ohm resistance, I should use a 4 layer pcb.

?Internship? and Autopilot Parts

2009-08-02T12:30:00.004-04:00

I have decided to look into getting an internship in an MIT lab next summer, and seeing what it would take to make it happen. I have found a scientist that may be able to help me network on campus.

My first parts for the autopilot came this week. They were free samples (hooray) of the exact part I need. They're from tyco electronics and are 7 position ffc sockets. .1" pitch.

I'm Back and Better Than Ever!

2009-07-22T11:43:00.002-04:00

I went on vacation this past week so I wasn't left with much time to research or post. But now that I'm back, I have nearly finished my PCB for the ADC break out board, and I've found my answer to how the IR sensor works when it is mounted at an angle. My holy grail came from here, and I was finally directed there by Chebuzz over on the Paparazzi forums. My equations are:

Pitch=(x+y)/2
Roll=(-x+y)/2

Woohoo! Now to work on the GPS and magnetometer guidance. That's gonna be interesting! Ublox here I come.

Well, I'm Back! And I've Been Asking More Questions!

2009-07-08T14:05:00.002-04:00

Alright, over the past fews days I have read 40 pages of technical data (that was loads of fun), but in the process I figured out the differences in all the versions of the MCP3208. I am going with the MCP3208 BI/SL. I chose the 'B' because it is more accurate than the 'C' and the 'I' just means it has an industrial temperature rating. 'SL' just means it has a SOIC package.

Once I figured that out, I started working on a PCB break out board for the ADC so it would be easier to work with. Once I finish that, I'll post a link to it on BatchPCB, SparkFun's cheap PCB prototyping service.

I have also started trying to figure out the functional theory behind the XY ir sensor and the way it is mounted. I get how the tempurature differences correlate to pitch and roll. What I don't get is how it works when mounted diagonally. You can follow how that goes here, or you can click the title of this post.

I got distracted.....

2009-07-03T15:41:00.002-04:00

I got distracted yesterday. I wound up spending the majority of my time in front of the TV with an ice pack on my purple-ish foot. When I wasn't doing that I was trying to set up my Google AdSense stuff and checking out Google Analytics.

I think I am going to use the MCP3208 or MCP3204 converter. They are 12bit, 8 and 4 channel ADC's. I'm leaning towards the 3208 because it already has a driver programmed in the Propeller Object Exchange (Obex). Now my only problem is figuring out the difference between all the different versions of the 3208. When I went to check their prices, I found that there are 5 different incarnations of the chip, each with a different suffix and a different price to match.

I Think I'm Gonna Have Some Extra Research Time...

2009-07-02T14:45:00.003-04:00

Last night I had the privilege of having my foot run over by a Nissan Xterra SUV. Luckily, I'm still a spry young man, therefore I still have rubbery bones. The incident left me with bruising, minor swelling, pain/tingly-numbness the entire length of the left part of my left foot, and a whole lot of extra time.

I will publish the results of my extra research time later today.

The Search Continues!

2009-07-01T23:04:00.002-04:00

Its been a light research day for me today. I only did an hour or so of searching. I'm still hunting down a good Sigma-Delta ADC. I'm still getting good help from the thread I posted. I plan to do more searching later tonight. Wish me luck, hopefully I'll be able to move on soon.

Sigma-Delta ADC's and Thermopiles

2009-06-30T13:15:00.004-04:00

I spent most of my day yesterday researching how to interface the ArduPilot XY sensor and the Paparazzi Z sensor to the Propeller. Upon registering with the Parallax forums, I started a new thread to help me along with my research. If you read the thread, you can see how things progressed and why I am trying to figure out how a Sigma-Delta Analog Digital Conversion works, or what it is for that matter, and how I am supposed to use it. Because the xy sensor has 2 analog output wires and the z sensor has only 1, for a total of 3 outputs, I decided to go with Leon's suggestion and use a multichannel ADC IC to handle the conversions, thus bypassing the need to make three of these things:

as described in a Parallax help document.
Now the search begins for an appropriate ADC IC.

First Post! And Introduction

2009-06-25T16:29:00.000-04:00

This site is where I will record and journalize my attempts at a GPS Autopilot for an R/C Vehicle, most likely a plane. The Autopilot will be based around the Parallax Propeller. This project is something I have been wanting to do since 6th grade, and now that I am a rising Sophomore, I need something to go on my application for college. My current college of choice is the Massachusetts Institute of Technology in Cambridge, Massachusetts. I have longed to go there since the age of 5 when I was living in Concord.