In this paper, mm-Pose, a novel approach to detect and track human skeletons
in real-time using an mmWave radar, is proposed. To the best of the authors'
knowledge, this is the first method to detect >15 distinct skeletal joints
using mmWave radar reflection signals. The proposed method would find several
applications in traffic monitoring systems, autonomous vehicles, patient
monitoring systems and defense forces to detect and track human skeleton for
effective and preventive decision making in real-time. The use of radar makes
the system operationally robust to scene lighting and adverse weather
conditions. The reflected radar point cloud in range, azimuth and elevation are
first resolved and projected in Range-Azimuth and Range-Elevation planes. A
novel low-size high-resolution radar-to-image representation is also presented,
that overcomes the sparsity in traditional point cloud data and offers
significant reduction in the subsequent machine learning architecture. The RGB
channels were assigned with the normalized values of range, elevation/azimuth
and the power level of the reflection signals for each of the points. A forked
CNN architecture was used to predict the real-world position of the skeletal
joints in 3-D space, using the radar-to-image representation. The proposed
method was tested for a single human scenario for four primary motions, (i)
Walking, (ii) Swinging left arm, (iii) Swinging right arm, and (iv) Swinging
both arms to validate accurate predictions for motion in range, azimuth and
elevation. The detailed methodology, implementation, challenges, and validation
results are presented.