<<PackageHeader(imu_filter_madgwick)>> <<TOC(4)>>

## AUTOGENERATED DON'T DELETE
## CategoryPackage

== Details ==

The [[imu_filter_madgwick]] package is used to filter and fuse raw data from IMU devices. It fuses angular velocities, accelerations, and (optionally) magnetic readings from a generic IMU device into an orientation quaternion, and publishes the fused data on the `imu/data` topic. The package has been tested using the raw data output of a Phidgets IMU (Spatial 3/3/3) device. The package is a wrapper of Sebastian Madgwick's IMU filter [1].

== Supported devices ==

The filter should be general enough to use with any IMU which publishes angular velocities and linear accelerations (and optionally magnetic field).

It has been tested with:

[[http://www.phidgets.com/products.php?product_id=1056_0 | Phidgets Spatial 3/3/3]]

== Example ==

Here's an example of the non-ROS version of the code, courtesy of Sebastian Madgwick.

<<Youtube(BXsGWoOMtmU)>>

Todo: similar video from rviz.

== ROS API ==

Two drivers are available: `imu_filter_node` and `imu_filter_nodelet`. Their parameters and topics are identical.

{{{
#!clearsilver CS/NodeAPI
sub {
   0{
    name = imu/data_raw
    type = sensor_msgs/Imu
    desc = Message containing raw IMU data, including angular velocities and linear accelerations.
    }
   1{
    name = imu/mag
    type = sensor_msgs/MagneticField
    desc = [optional] Magnetic field vector; the type is either `sensor_msgs/MagneticField` or `geometry_msgs/Vector3Stamped` (deprecated), depending on the parameter `use_magnetic_field_msg` (see below)
    }
  }
 pub {
   0{
    name = imu/data
    type = sensor_msgs/Imu
    desc = The fused Imu message, containing the orientation.
   }
  }

  # Autogenerated param section. Do not hand edit.
  param {
    group.0 {
      name=Dynamically Reconfigurable Parameters
      desc=See the [[dynamic_reconfigure]] package for details on dynamically reconfigurable parameters.
      0.name= ~gain
      0.default= 0.1
      0.type= double
      0.desc=Gain of the filter. Higher values lead to faster convergence but more noise. Lower values lead to slower convergence but smoother signal. Range: 0.0 to 1.0
      1.name= ~zeta
      1.default= 0.0
      1.type= double
      1.desc=Gyro drift gain (approx. rad/s). Range: -1.0 to 1.0
      2.name= ~mag_bias_x
      2.default= 0.0
      2.type= double
      2.desc=Magnetometer bias (hard iron correction), x component. Range: -10.0 to 10.0
      3.name= ~mag_bias_y
      3.default= 0.0
      3.type= double
      3.desc=Magnetometer bias (hard iron correction), y component. Range: -10.0 to 10.0
      4.name= ~mag_bias_z
      4.default= 0.0
      4.type= double
      4.desc=Magnetometer bias (hard iron correction), z component. Range: -10.0 to 10.0
      5.name= ~orientation_stddev
      5.default= 0.0
      5.type= double
      5.desc=Standard deviation of the orientation estimate. Range: 0.0 to 1.0
    }
    # End of autogenerated section. You may edit below.
    group.1 {
      name=Not Dynamically Reconfigurable Parameters

      0.name = ~world_frame
      0.type = string
      0.default = `"nwu"` for Indigo - Kinetic, `"enu"` for Lunar+
      0.desc = The world frame with respect to which the orientation is indicated (see [[https://github.com/paulbovbel/rep/blob/5b0c670130da8222ab28d5aba75dce5a26442ffe/rep-0145.rst | REP-145]]). For historic reasons, the old default is "nwu" (North-West-Up). New deployments should use "enu". Valid values: "nwu", "enu", "ned".
    
      1.name = ~use_mag
      1.type = bool
      1.default = `true`
      1.desc = Whether to use the magnetic field data in the data fusion.
  
      2.name = ~use_magnetic_field_msg
      2.type = bool
      2.default = `false` for Hydro and Indigo, `true` for Jade+
      2.desc = If set to `true`, subscribe to the `/imu/mag` topic as a `sensor_msgs/MagneticField`; if set to `false` (deprecated), use `geometry_msgs/Vector3Stamped`.

      3.name = ~fixed_frame
      3.type = string
      3.default = `odom`
      3.desc = The parent frame to be used in `publish_tf`.
  
      4.name = ~publish_tf
      4.type = bool
      4.default = `true`
      4.desc = Whether to publish a TF transform that represents the orientation of the IMU, using the frame specified in `fixed_frame` as the parent frame and the frame given in the input imu message as the child frame.
  
      5.name = ~reverse_tf
      5.type = bool
      5.default = `false`
      5.desc = If set to `true`, publish transforms from `imu_frame` to `fixed frame` instead of the other way around.
  
      6.name = ~constant_dt
      6.type = double
      6.default = 0.0
      6.desc = The dt to use; if 0.0 (default), compute dt dynamically from message headers.
  
      7.name = ~publish_debug_topics
      7.type = bool
      7.default = `false`
      7.desc = If set to `true`, publish a couple of debug topics.
  
      8.name = ~stateless
      8.type = bool
      8.default = `false`
      8.desc = If set to `true`, don't publish a filtered orientation. Instead, publish the stateless estimate of the orientation based on the latest accelerometer (and optionally magnetometer) readings alone. Useful for debugging.

      9.name = ~remove_gravity_vector
      9.type = bool
      9.default = `false`
      9.desc = If set to `true`, subtract the gravity vector from the `acceleration` field in the published IMU message.
    }
  }
}}}

== References ==

[1] http://www.x-io.co.uk/open-source-imu-and-ahrs-algorithms/

== Bug Reports & Feature Requests ==

We appreciate the time and effort spent submitting bug reports and feature requests.

<<GitHubIssues(CCNYRoboticsLab/imu_tools)>>

## AUTOGENERATED DON'T DELETE
## CategoryPackage