Tutorials
The role of the tutorials is to provide a platform for a more intensive scientific exchange amongst researchers interested in a particular topic and as a meeting point for the community. Tutorials complement the depth-oriented technical sessions by providing participants with broad overviews of emerging fields. A tutorial can be scheduled for 1.5 or 3 hours.
Tutorial proposals are accepted until:
September 14, 2026
If you wish to propose a new Tutorial please kindly fill out and submit this
Expression of Interest form.
Tutorial on
Wearable IMUs in Human Movement Analysis: An Engineering Perspective on
Theory and Applications
Instructor
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Kerem Altun
Yildiz Technical University
Türkiye
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Short Bio
Dr. Kerem Altun received his B.S. and M.S. degrees in Mechanical Engineering from Middle East Technical University, and his PhD degree in Electrical and Electronics Engineering from Bilkent University, both located in Ankara, Türkiye. After postdoctoral research at the Sensory Perception and Interaction Laboratory at the University of British Columbia, and teaching experience in various universities, he is currently a faculty member at the Department of Control and Automation Engineering at Yildiz Technical University in Istanbul, Türkiye. His current research interests include wearable inertial sensing, biomechanics, human movement analysis, sensor data fusion and machine learning.
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Abstract
An inertial measurement unit (IMU) usually comprises a 3-axis accelerometer, a 3-axis gyroscope, and a 3-axis magnetometer. In the past 30 years, wearable IMUs have increasingly been used in many applications such as motion capture, activity analysis, rehabilitation, pedestrian localization, gaming, and sports. Accelerometers measure the 3D acceleration vector components of the point that they are mounted on, whereas gyroscopes measure the 3D angular velocity components of the rigid body (limb) that they are attached to. However, these vector components are measured in the sensor coordinate system, whose orientation continuously changes during motion. In many sports applications, it is usually required to determine the velocities and/or positions of body parts in a fixed coordinate system. Therefore a coordinate transformation is necessary, and the orientation of the sensor coordinate system with respect to the fixed coordinate system should be determined for this purpose. Because of inertial sensor drift, this is usually performed through the use of a Kalman filter. Some commercial IMUs have built-in Kalman filters that provide orientation data in terms of Euler angles, orthogonal matrices, or quaternions.
In the paragraph above, there are many terms that a new wearable inertial sensor researcher frequently comes across: 3D kinematics, position, velocity, acceleration, orientation, drift, coordinate transformations, Kalman filter, quaternions, etc. However, in our experience, many new researchers do not have a good command of these concepts. In this tutorial, I will provide a gentle introduction to these concepts by giving examples from wearable IMU research that exists in literature. Although the discussed concepts are related to mathematics and engineering, the tutorial will be tailored for an audience in sport science and will involve basic concepts. I will make use of visual aids such as GeoGebra in order to help students visualize 3D vectors, rotations, and motion in general. I will also use a real IMU to demonstrate the concepts introduced.
Keywords
Inertial sensors, kinematics, coordinate transformations, orientation
Aims and Learning Objectives
This tutorial aims to provide the participants with sufficient background information about 3D kinematics in order to correctly interpret data collected from inertial sensors worn on the body. After the tutorial, the attendees are expected to have basic idea about 3D position, velocity and acceleration vectors; coordinates and transformations; orientation representation with Euler angles, rotation matrices and quaternions; inertial sensor drift, its causes and solutions; use of wearable inertial sensors in different research applications.
Target Audience
The tutorial is intended for graduate students from sport science background that are interested in learning more about basic concepts related to 3D kinematics and wearable inertial sensing.
Prerequisite Knowledge of Audience
Basic physics, position, velocity and acceleration; basic geometry, mathematics and matrix algebra
Detailed Outline
1. Vectors and coordinate systems
2. Particle kinematics
2.1. Particle motion on a line: velocity and acceleration
2.2. Particle motion on a curve: tangential and normal acceleration
2.3. Measuring acceleration: accelerometers
2.4. Drift
2.5. Estimating velocity and position: the integral
2.6. Motion on a 3D curve
3. Overview of particle dynamics (may be skipped)
3.1. Force and motion: Newton's 2nd Law
3.2. Kinetic energy and potential energy
4. Rigid Body Kinematics (2D)
4.1. Fixed point rotation: angular velocity and acceleration
4.2. General motion: translation+rotation
4.2. Measuring 2D rotation: gyroscopes
4.3. Drift in 2D
4.4. Representing 2D rotation: complex numbers and matrices
4.5. Estimating velocity and position
5. Rigid body kinematics (3D)
5.1. Orientation in 3D: direction cosines
5.2. Direction cosine matrix
5.3. Rotation sequences in 3D
5.4. Representing 3D rotation: quaternions
5.5. Sensor coordinates and fixed coordinates