Biomedical Engineering Reference
In-Depth Information
Chapter 8
Contact Modeling and Collision Detection
in Human Joints
Ehsan Arbabi and Daniel Thalmann
8.1 Introduction
Using computer aided simulations for investigating the joints behavior in normal and
pathological cases [
1
] could be proven to assist physicians to diagnose the illness
faster and more accurately, and also to achieve a more precise surgical plan, [
2
-
9
].
Human joint simulations usually starts by reconstructing three dimensional meshes
of the joint tissues (bones, cartilages, etc) fromCT or MR Images [
10
] and estimating
the center of rotation such as for the hip [
7
,
11
]. Once the three-dimensional model
is constructed, the critical task to handle can be the precise detection of collisions
between virtual tissues so that the stresses in the colliding areas are faithfully evalu-
ated [
4
,
8
,
9
,
12
] or the range of motion in a specific orientation is correctly estimated
[
3
,
6
,
7
].
Most of the methods for collision detection are for general/semi-general purposes
and therefore they may not be considered as an optimum method in specific appli-
cations. This generality can be problematic in case we need higher speed and still
accurate results, especially when the other time consuming computations may be
done in parallel to the collision detection.
In Sect.
8.2
, two recent accurate and fast collision detection methods for rotating
or sliding objects will be explained. In addition to detecting the collisions faster than
general methods, they also return penetration depths in either radial or cylindrical
direction. In general, themethods are capable of detecting the collisions and returning
the penetration depths in the applications that the movement is modeled as either
rotation or sliding [
13
,
14
].
