Figure 5. The 3DM module by MICROSTRAIN

3DM is a 3-axis orientation sensor capable of measuring: ± 180 degrees of yaw heading, ± 180 degrees of pitch, and ± 70 degrees of roll. Orthogonal arrays of magnetometers and accelerometers are used to compute the pitch, roll and yaw angles over a wide angular range. The 3DM is sold as a starter kit for the first unit purchased, after which, just the board can be purchased. The starter kit includes the standard board, enclosure (shown), software, requisite serial communications and power cable, and a manual. The Windows® software provided communicates with 3DM over a serial port. The software gives the user complete control over how data is processed, presented, and logged. The output may be programmed to provide raw magnetic field and accelerometer outputs, or processed pitch, roll, and yaw outputs. User programmed digital filters are used to process sensor data either statically or dynamically, depending on the change in 3DM movement over time. 3DM runs off of a single supply positive voltage ranging from 5.3 to 12 volts DC. 3DM's can be used alone or combined in networked arrays.


      yaw: ± 180 degrees
      pitch: ± 180 degrees
      roll: ± 70 degrees
A/D Resolution: 12 bits
Digital Filter: Infinite Impulse Response (IIR)User programmable weighted moving average Angle Resolution (no digital filtering):
      Pitch: 0.30 degrees (typical)
      Roll: 0.25 degrees (typical)
      Yaw: 0.50 degree (typical)
Angle Resolution (most aggressive digital filtering)
      Pitch: < 0.1 degrees
      Roll: < 0.1 degrees
      Yaw: < 0.1 degrees
Resolution specs. taken during static motions
Accuracy (defined as the square root of the sum of the errors squared - non repeatability, temperature coefficients & no linearity)
      Pitch: ±0.93 degree typical (yaw from 0 - 360 degrees & roll=0 degrees)
      Roll: ±0.33 degree typical (yaw from 0 - 360 degrees & pitch =0 degrees)
      Yaw: ±1.0 degrees typical (pitch & roll=0 degrees)
Angle measurement non linearity (pitch & roll): ±0.23% F.S.
Angle measurement repeatability
      Pitch: 0.07 degrees (typical)
      Roll: 0.07 degrees (typical)
      Yaw: 0.26 degrees (typical)
Update rate (angle mode) - specified with a maximum and typical value since it depends on how many points the A/D converter averages:
      45 Hz/ 3 channels (maximum)
      30 Hz/ 3 channels (typical)
Update rate (raw mode): 70 Hz/ 6 channels
Output modes
      raw: ax,ay,az accelerometer
      raw: bx,by,bz magnetic field
      units: pitch, roll, & yaw in degrees
Output format: RS-232 serial or RS-485 multi drop networkA
Transmission Rate: 9600 bits/sec
Supply voltage: 5.3 volts DC min
Supply current: 50 milliamps/node @ standard speed
Connectors: Sensor RJ11 type (power: min. coaxial jack) Operating Temperature: -25 degrees C to 70 degrees C Temperature Drift (%/ deg. C) (mean, std.dev.):
      Pitch: 0.009+/-0.008
      Roll: 0.033+/-0.025
      Yaw: 0.019+/-0.019
Module size: 1.7" wide, 2.5" long, 0.7" thick