# Switching State Estimators
This page shows you which state estimators are available and how you can switch between them.
TIP
EKF2 is highly recommended for all purposes (LPE is no longer supported/maintained).
# Available Estimators
The available estimators are:
- EKF2 attitude, position and wind states estimator - EKF2 is an extended kalman filter estimating attitude, 3D position / velocity and wind states.
- LPE position estimator - The LPE position estimator is an extended kalman filter for 3D position and velocity states.
- Q attitude estimator - The attitude Q estimator is a very simple, quaternion based complementary filter for attitude.
# How to Enable Different Estimators
For multirotors and VTOL use the parameter SYS_MC_EST_GROUP to choose between the following configurations (LPE is not supported for Fixed Wing).
| SYS_MC_EST_GROUP | Q Estimator | LPE | EKF2 |
|---|---|---|---|
| 1 | enabled | enabled | |
| 2 | enabled | ||
| 3 | enabled |
Note
For FMU-v2 (only) you will also need to build PX4 to specifically include required estimator (e.g. EKF2: make px4_fmu-v2, LPE: make px4_fmu-v2_lpe).
This is required because FMU-v2 is too resource constrained to include both estimators.
Other Pixhawk FMU versions include both.