Goal:
The goal of this project is to develop a working digital compass that is capable of the precision required for cave surveying.
Scope:
The first (alpha one) compass will only be used to evaluate whether the LSM303DLHC digital compass module is capable of the precision required for cave surveying applications. This compass will contain a compass, inclinometer, and laser pointer. Other functions such as memory recording, bluetooth transmission, or integration with a laser distance meter will not be considered in the first iteration.
Unique Considerations:
Evaluation Criterion:
Test Plan:
The goal of this project is to develop a working digital compass that is capable of the precision required for cave surveying.
Scope:
The first (alpha one) compass will only be used to evaluate whether the LSM303DLHC digital compass module is capable of the precision required for cave surveying applications. This compass will contain a compass, inclinometer, and laser pointer. Other functions such as memory recording, bluetooth transmission, or integration with a laser distance meter will not be considered in the first iteration.
Unique Considerations:
- The LSM303DLHC is a 3-d compass and will allow the compass to give directions regardless of what inclination it is pointing.
- This project will use a non-magnetic battery and a regulated power supply in order to decrease the soft-iron effects that most digital compasses suffer from. This battery was designed for use in MRI medical applications.
- The compass will be programmed using an Arduino platform in order to make the project easy to replicate, test and improve on.
- The compass will only be tested in Kentucky. Magnetic fields in other parts of the world will vary and affect the results accordingly.
Evaluation Criterion:
- Compass Accuracy
- Compass Precision
- Repeat-ability of measurements
- Affects of temperature on readings
- Affects of inclination on compass readings
- Comparison to results with Suunto compass
Test Plan:
- Determine the resolution of the compass in fractions of a degree and determine the useable resolution when hand-held with jitter
- Acquire 3-d plots of the output of the compass at room temperature
- Create a fixture that allows the compass to be repeatedly be pointed in a series of directions in all 3 axis'
- Determine the drift of the compass at room temperature over multiple days
- Determine the drift of the compass at various temperatures by doing heat soak and cold soak testing
- Determine the drift of the compass over multiple charge and discharge cycles of the battery
- Compare the digital compass to the Suunto analog compass by having multiple experienced users survey a fixed figure-8 course with both sets of equipment