|
|
|
|
|
|
SYSTEM FOR NON-CONTACT MEASUREMENT
1995Download the complete report (500 KB, PDF format) |
 get adobe acrobat reader |
Bearsley A, Brown T I H, Ng K-Centre for Biomedical Engineering
Andrew Beasley- Biomedical Engineering (Monash University) undertook a study involving the programming and application of three dimensional imaging to lower limb anatomical features in particular a trans-tibial stump.
A system known as Computer Aided Non-contact Volumetric Analysisof Stumps (referred to as CANVAS) was designed to measure accurately the shape and volume of a below-knee stump. The CANVAS System was designed to be used in a clinical environment, allowing precise quantification of volumetric changes that are occurring in the residual limb.
CANVAS uses the Monash 3-D Shape Measurement System for acquiring stump surface data. The measurement system consists of a Charge Coupled Device camera and a light projector with a liquid crystal filter.
The Shape Measurement System projects a series of stripes onto the stump, then uses triangulation to calculate a set of discrete points on the stump surface. At least 5 measurements from around the stump are required to cover the full 360 degree surface. CANVAS processes the data sets, merging them into a cylindrical model representing the surface. Multiple surfaces were superimposed and presented graphically, allowing visual comparison.
The prototype CANVAS System was tested on a plaster case of a below-knee stump, simulating volumetric changes with plasticine.These localised volumetric changes could be clearly quantified.
