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version 0.7.5

Python utilites for movements in 3d space

People: Thomas Haslwanter



*scikit-kinematics* primarily contains functions for working with 3D
kinematics, e.g quaternions and rotation matrices.
This includes utilities to read in data from the following IMU-sensors:
- XSens
- xio

Compatible with Python >= 3.5

numpy, scipy, matplotlib, pandas, sympy, easygui


Author: Thomas Haslwanter
Date: 19-02-2018
Ver: 0.7.5
Licence: BSD 2-Clause License (
Copyright (c) 2018, Thomas Haslwanter
All rights reserved.

You can install scikit-kinematics with

pip install scikit-kinematics

and upgrade to a new version with

pip install scikit-kinematics -U


Analysis of signals from IMUs (intertial-measurement-units).
Read in data, calculate orientation (with one of the algorithms below)

- get_data ... This method must be taken from one of the existing sensors,
or from your own sensor. Currenlty the following sensors types are available:
* XSens
* xio (original, and NGIMU)
* yei
* polulu
- calc_position

MARG Systems
- imus.analytical ... Calculate orientation and position, from angular velocity and linear acceleration
- imus.kalman ... Calculate orientation from IMU-data using an Extended Kalman Filter.

- imus.IMU ... Class for working with data from IMUs
- imus.IMU.calc_position ... calculate position
- imus.IMU.setData ... set the properties of an IMU-object
- imus.Madgwick ... Class for calculating the 3D orientation with the Madgwick-algorithm
- imus.Mahony ... Class for calculating the 3D orientation with the Mahony-algorithm


Analysis of signals from video-based marker-recordings of 3D movements

- markers.analyze_3Dmarkers ... Kinematic analysis of video-basedrecordings of 3D markers
- markers.find_trajectory ... Calculation of joint-movements from 3D marker positions


Note that all these functions work with single quaternions and quaternion vectors,
as well as with arrays containing these.

Quaternion class

- quat.Quaternion ... class, including overloading for multiplication and
division (e.g. \"quatCombined = quat1 * quat2\"), import and export

Functions for working with quaternions

- quat.q_conj ... Conjugate quaternion
- quat.q_inv ... Quaternion inversion
- quat.q_mult ... Quaternion multiplication
- quat.q_scalar ... Extract the scalar part from a quaternion
- quat.q_vector ... Extract the vector part from a quaternion
- quat.unit_q ... Extend a quaternion vector to a unit quaternion.

Conversion routines - quaternions

- quat.calc_angvel ... Calculates the velocity in space from quaternions
- quat.calc_quat ... Calculate orientation from a starting orientation and angular velocity.
- quat.convert ... Convert quaternion to corresponding rotation matrix or Gibbs vector
- quat.deg2quat ... Convert number or axis angles to quaternion vectors
- quat.quat2seq ... Convert quaternions to sequention rotations (\"nautical\" angles, etc)
- quat.scale2deg ... Convert quaternion to corresponding axis angle

Rotation Matrices

Definition of rotation matrices

- rotmat.R ... 3D rotation matrix for rotation about a coordinate axis

Conversion Routines - rotation matrices
- rotmat.convert ... Convert a rotation matrix to the corresponding quaternion
- rotmat.seq2quat ... Convert nautical angles etc. to quaternions
- rotmat.sequence ... Calculation of Euler, Fick, Helmholtz, ... angles

Symbolic matrices

- rotmat.R_s() ... symbolix matrix for rotation about a coordinate axis

For example, you can e.g. generate a Fick-matrix, with

>>> R_Fick = R_s(2, \'theta\') * R_s(1, \'phi\') * R_s(0, \'psi\')

Spatial Transformation Matrices

- rotmat.stm ... spatial transformation matrix, for combined rotations/translations
- rotmat.stm_s() ... symbolix spatial transformation matrix

Denavit-Hartenberg Transformations

- rotmat.dh ... Denavit-Hartenberg transformation matrix
- rotmat.dh_s ... symbolic Denavit-Hartenberg transformation matrix


Routines for working with vectors
These routines can be used with vectors, as well as with matrices containing a vector in each row.

- vector.normalize ... Vector normalization
- vector.project ... Projection of one vector onto another one
- vector.GramSchmidt ... Gram-Schmidt orthogonalization of three points
- vector.q_shortest_rotation ... Quaternion indicating the shortest rotation from one vector into another.
- vector.rotate_vector ... Rotation of a vector
- vector.target2orient ... Convert target location into orientation angles

Interactive Data Analysis

- viewer.ts ... interactive viewer for time series data



You can download the latest distribution from PyPI here:

Using pip

You can install scikit-kinematics for yourself from the terminal by running:

pip install --user scikit-kinematics

If you want to install it for all users on your machine, do:

pip install scikit-kinematics
On Linux, do sudo pip install scikit-kinematics.

If you don't yet have the pip tool, you can get it following these instructions.

This package was discovered in PyPI.