Multi-Axis Scan

A field survey measured along more than one axis: four horizontal arms out from the center of the accessory, and then that whole pattern again at each height above it. The horizontal arms are named x-, x+, y- and y+, and each is swept at the same height, so readings taken at equal distances on different arms compare directly. Measuring all four is what makes directional bias visible. A coil that reads strong on one arm and weak on the opposite arm points to uneven winding, a shifted core, or a probe that drifted off center, and a single-axis scan averages that away. Repeating the sweep at increasing heights adds the z-axis, which is what turns a surface map into a picture of how far the field reaches. The two halves feed different results: Field Symmetry reads only the four horizontal arms and cannot be reported unless all four carry readings, while Penetration Depth reads the stack of heights and needs at least one plane above the surface. The center reading sits where the arms cross and is shared by all of them, so it is recorded once and left out of the symmetry comparison. See Scan Grid, X-Axis / Y-Axis, Z-Axis and Field Symmetry.