Skip to content
ENExplore Calculators

IMU Drift Estimate Calculator

Work out imu drift estimate instantly with clear inputs, formula shown and shareable results.

About IMU Drift Estimate Calculator

Gyro bias integrates linearly with time while angle random walk grows with the square root of time, so bias dominates over long intervals. Accelerometer bias is worse still for position: it integrates twice, so error grows with the square of time — 0.02 m/s² gives 144 m after two minutes.

Formula

IMU drift

bias drift = bias x t; random walk = ARW x sqrt(t); position drift = 0.5 x accel bias x t^2

Worked example

With the default values below, IMU Drift Estimate Calculator returns Heading drift of 0.2681. Change any input above and every figure here is recalculated in your browser.

Inputs used

Gyro bias stability
8 °/h
Angle random walk
0.15 °/√h
Integration time
120 s
Accelerometer bias
0.02 m/s²

Results

Heading drift
0.2681 °
Drift from bias
0.2667 °
Drift from random walk
0.0274 °
Position drift from accelerometer bias
144.00 m

Step by step

  1. 1Values used
  2. 2IMU drift
  3. 3Heading drift= 0.2681 °
  4. 4Drift from bias= 0.2667 °
  5. 5Drift from random walk= 0.0274 °
  6. 6Position drift from accelerometer bias= 144.00 m

Assumptions and limits

  • The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
  • In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
  • Figures are rounded for display to 4 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

Why is dead reckoning from an IMU alone hopeless?

Because position error grows with time squared. Even a very good MEMS unit accumulates hundreds of metres within minutes without an external reference.

What corrects IMU drift?

Fusion with absolute references: GNSS, wheel odometry, magnetometer heading or visual/lidar odometry, usually in a Kalman filter.

Related Calculators

IMU Drift Estimate Calculator | Calcrivo