A device to accurately measure inclination and/or heading in a static or dynamic environment would be useful as a feedback element for vibration and position control in adaptive structures. Our goal was to develop a miniature, sourceless angle measurement system, which utilizes triads of accelerometers and magnetometers as well as an onboard microprocessor (3DM). The microprocessor calculates pitch, roll, and yaw based on Earth's magnetic and gravitational field vectors. The microprocessor also incorporates a digital user programmable infinite impulse response (IIR) filter. This paper describes the ability of 3DM to accurately measure angle in static and dynamic environments. Static as well as four dynamic test configurations were performed: 100, 500, 1000 Hz and Gaussian white noise. The IIR cutoff frequency was set at 0.5, 5, and 30 Hz for each test. Results indicate that implementing an IIR filter can improve measurement accuracy. When the 3DM was oscillated at 100 Hz, error on the pitch axis changed from 1 degree to 0.15 degrees peak to peak using IIR filter cutoff frequencies of 30 and 0.5 Hz respectively. The roll axis responded similarly. Its error was reduced from 2 degrees to 0.1 degrees peak to peak when the IIR cutoff frequency was reduced from 30 Hz to 0.5 Hz.