By Feature

2-axis Measurement

A 2-axis compass module consists of two magnetic sensors placed at right angles to each other. Although they are accurate only when held to a level orientation, 2-axis compasses are a cost-effective alternative to 3-axis or 3D orientation modules when 3 axes of measurement aren't required.

3-axis Measurement

3-axis sensor modules incorporate three magnetometers to measure magnetic field on the X, Y, and Z axes. Most PNI 3-axis modules are also 3D orientation (or tilt-compensated) modules, including an onboard accelerometer to enable space mapping in three dimensions.

3D Orientation

Unlike modules that are accurate only at a perfectly level orientation, 3D orientation (also called tilt-compensated) modules map space accurately in three dimensions. PNI's 3D orientation modules include an integrated accelerometer that senses the Earth's gravity vector, enabling them to provide accurate heading, pitch, and roll (azimuth) regardless of the tilt applied —up to 360 degrees, depending on the specific module.

Acceleration and Tilt Measurement

PNI tilt-compensated modules are engineered with high-resolution accelerometers that provide the accurate tilt and acceleration information critical to calculating sub-1° heading accuracy at all orientations. Tilt-compensated modules output 3-axis accelerometer, pitch and roll measurements — and unlike 2-axis compasses, they do not have to remain physically level.

Compass Heading and Azimuth

Digital compass functions can be configured for either 2- or 3-axis measurement, depending on the number of integrated magnetometers. A 2-axis compass is ideal for applications where the compass is gimballed or fixed in a level orientation. For accurate compass heading in any orientation, a 3-axis tilt-compensated module is required.

Hard- and Soft-Iron Correction

In addition to hard-iron distortions caused by permanent magnets or magnetized steel and iron, magnetic sensor readings are subject to distortions caused by interactions between the Earth's magnetic field and magnetically "soft" materials and fields. Several PNI modules include built-in algorithms that correct for the effects of both hard- and soft-iron interference, calibrating out magnetic anomalies and distortion for reliable, repeatable high-accuracy measurement in any environment.

Hard-Iron Correction

Hard-iron distortions are caused by proximity to permanent magnets or magnetized steel or iron objects, which can corrupt magnetic sensor readings. PNI ready-to-integrate modules include built-in algorithms that compensate for the effects of hard-iron interference using a simple subtraction method.

High-Resolution/Accuracy

All PNI magneto-inductive sensors and modules provide higher resolution and accuracy than competing sensor technologies. Throughout our site, the designation “high resolution/accuracy” applies to the best of the best — sensors and modules that offer higher resolution even compared to other PNI sensors.

Low Power

PNI's patented magneto-inductive sensors draw as little as 1/12 the power of ordinary magneto-resistive sensors, which not only draw more power when idle but also require constant current pulses (one per second) to reset the sensor between readings. Throughout our site, the designation “low power” applies to our most energy-efficient sensors and modules, with power demands that are low even compared to other PNI sensors.