with cheaper 3 axis digital gyros and Accelerometers coming out like the Itg 3200 and bma180, for under $70 it would be possible to make a highly accurate digital imu. (for the prototype, around $50 for a production version, but still cheaper than almost any other imu)
so i started thinking, what format (shield, board, package) would an imu like this be most useful in? the ardupilot is a pretty common board for uavs and it already has an an imu for it, but the arduimu isn't the easiest to integrate or use.
although one of the easiest things to integrate and use is a shield, so an imu shield for the ardupilot should probably have at least 4 things:
- a 3 axis gyro
- a 3 axis Accelerometer
 (for the imu)
- a barometric pressure sensor
 (for much better altitude reading)
- i2c ports (3.3v and 5 v)
 (because i2c is really common)

with this goal in mind I started looking for parts, and after looking around for a bit i found the following main parts.

for the gyro the ITG-3200 is pretty much my only choice
for the accel the BMA180 will be more than accurate enough.
also the BMP085 should be a good pressure sensor,
and for the i2c logic level translation i will have the 296-18509-1-ND
which is the same IC Diydrones uses.

time to create a board,eagle designs should be posted in a day or two

here are the eagle files v1.brd, v1.sch
this is my first eagle schematic except for the eagle tutorial at sparkfun, so please tell me what you think.

also some thing i think is wrong on the board is the header placement for the ardupilot.
do they just look wrong or do they really need to be fixed?

any help on this project would be appreciated.

update; here is the final version of the board:
v2.brd
v2.sch

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nice work !
i am currently working with a friend to perfect the design, then i will post results
the board has been ok'ed and i am currently sourcing all parts, stay posted
ii have hit a wall in parts not being avalable for a couple weeks but i re calculated mu cost and came up with about $30
for a board (prototype)
i have switched the bma 180 to a axl345 as it is cheaper and readially avalible
Low cost DIY IMU? That sounds awesome. Thanks for publishing this. It looks really professional.

Up until now I've been avoiding such a project as it seemed intimidating, but I'd love to be part of a group buy.
thanks, I haven't had much time to work on it lately as I am going to high school but, once I get the hardware built I could use some help on programming if you are any good at that (im not). ill post the current parts list when I get around to it.

Hi Marshall

 

What size are tthe components and how would the boards come to me

 

Pete

it says in the discription with links to the parts, they are qfn chips (i think) and the board will be slightly larger than an inch square.

it has been a while sience I did much on this project beacuse I was lacking the proper tools and skills to solder this board. it hasent been sent to the pbc fab house for this reason either.

thanks

i was more thinking of the resistor and caps are they 0603.

If you are going to get the boards made get them made as a panel some thing like 5x5 or some thing like that/

 

I designed a rc switch that is .5x.75 and i have them on a panel the is 5x10 so on one board i have 50 of them.

 

pete

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