I've seen some reports out there on modifying a laser disto to show digital compass and inclination readings, but most of the documents I can find are several years old and use outdated technology or obsolete distos. I was wondering if anyone out there has recent experience. I'm looking at building my own that will work in a newer model ditance meter. Possibly making some changes so that it will be possible to calibrate for multiple devices.
I'm thinking about using an LSM303DLHC digital compass and accellerometer to make a tilt-compensated compass and then connect that to a laser disto using one of the methods I've seen in previous reports. This compass has a resolution of 2mGauss which should equate to easily .5 degree resolution. Haven't had time to work the numbers to figure out the accuracy yet.
Thoughts are this:
Remove the battery pack and connect an external battery pack with regulators both in the battery pack and in the disto (to decrease soft-iron effects).
In place of the battery pack put a circuit with the tilt compensated compass.
Have the microcontroller for the compass module read normal outputs to the LCD and overwrite with compass data to the LCD screen.
Have access to calibration buttons through the battery case door for calibration of the digital compass.
The digital compass should be calibrated to magnetic north as accurately as possible. Whenever soft-iron effects could change the compass will need to be re-calibrated.
Anyone have any experience with this chip? Any advice or time-savers?