A Dynamic Magnetic Technique for Sensing Block Motion.
Abstract
We report the development of a technique for dynamically sensing relative displacements; the intended application is for the measurement of block motion due to an underground explosion. The technique utilizes a permanent bar magnet and a magnetometer system located about a meter from the magnet. Relative motoin between the magnet and magnetometer system leads to a time-varying magnetometer signal. The well-known properties of a magnetic dipole allows the magnet's relative position to be derived from the observed signals. We discuss hardening of the magnetometer to withstand ground shock. We also show that the magnetometer system must measure both the magnetic field vector and (approximately) one component of the field's gradient in order to reliably infer the magnet's position from the observed signals. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 30, 1978
- Accession Number
- ADA066601
Entities
People
- P. Coleman