Data processing: measuring – calibrating – or testing – Measurement system – Orientation or position
Patent
1996-11-22
1999-06-08
Barlow, John
Data processing: measuring, calibrating, or testing
Measurement system
Orientation or position
36447405, 36447424, 36447425, 382108, 382154, G05B 1942, A61B 5107
Patent
active
059111267
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a method and an arrangement for digitized three-dimensional sensing of the shape of bodies or body parts, particularly human body parts or limbs, for largely automated production of artificial limbs or adapted moldings in which the body or body part together with a high-contrast pattern on the surface thereof is imaged by several cameras cooperating in the manner of stereo cameras having overlapping image areas and in which the digitized data of the three-dimensional shape are obtained by automatical coordination of corresponding patterns recorded in the images by means of a computer.
A method of this kind is known from the East German Patent 78 310 for the purpose of sensing anthropometric data. In this method, by making use of a stereo measuring camera, one or more images are produced from one side of the body of a test person after assuming a specified stance and fixing this by a suitable device, the body surface being previously provided with a shaded or raster structure by an arrangement of structure walls and light sources. The stereo images are evaluated by means of stereo autographs or stereo comparators and the data obtained from the images are evaluated and further processed by automatic electronic processor means.
This method is not well suited for three-dimensionally sensing the shape of bodies or body parts for largely automated production of artificial limbs or adapted moldings. For this purpose namely the body or body part needs to be imaged from various sides in as short a time as possible, preferably simultaneously, since the patient must not move during optical sensing. Meeting this requirement is particularly opposed by the structured illumination by means of structure walls and light sources which cannot be done at the same time for the various imaging directions. Since optical sensing needs to be done also independently of skin type and possible hirsuteness, complicated and time-consuming preparatory measures are needed, such as applying a reflective make-up or even depilation by shaving.
Furthermore, hygiene problems are involved. Since parts of the imaging equipment successively come into contact with naked body parts of various patients, it is necessary to configure these parts so that they can be regularly disinfected. Permitting disinfection necessitates the use of expensive materials which just like the time needed for disinfection increases the costs involved.
It is known, on the other hand, to sense the shape of body parts or limbs three-dimensionally by means of active laser scanners. In a method known from the PCT publication WO 92/08175 a single line of light is projected by means of a laser source on the body part covered by a thin, elastic envelope, this light line tracking the profile of the body part. By triangulation with the aid of an optical sensor the three-dimensional coordinates of the individual points of this profile line are determined. This procedure is repeated for further profile lines, a rotary table carrying the laser scanner being rotated each time by a small angle until in conclusion the body part has been completely sensed. In this known system it is also provided for that critical locations of the body part are characterized by markings on the envelope which do not reflect the laser light. These systems operating with active laser scanners are, however, as compared to photogrammetric systems employing passive stero cameras, highly expensive. Furthermore, there is the problem that even in the case of fast-working systems totally sensing a body part three-dimensionally takes up roughly 10 to 15 seconds in which the body part must not be moved.
As compared to this, the object of the invention is to provide a passive photogrammetric multi-camera method which permits, at little expense, very fast three-dimensional sensing of the shape of a body or body part, eliminating the need for preparatory measures concerning the body or body part to be imaged and having no need for disinfection whilst meeting the hygiene requirements.
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REFERENCES:
patent: 4697240 (1987-09-01), Cedar et al.
patent: 4745290 (1988-05-01), Frankel et al.
patent: 4819660 (1989-04-01), Smith
patent: 4821200 (1989-04-01), Oberg
patent: 4969106 (1990-11-01), Vogel et al.
patent: 4982438 (1991-01-01), Usami et al.
patent: 5127420 (1992-07-01), Horvath
patent: 5432703 (1995-07-01), Clynch et al.
F. Carrico, "Rapid Anthropometry for CAD/CAM Design in Prosthetics and Orthotics", RESNA 12th Annual Conference, New Orleans, Louisiana, p. 157, 1989.
Jack L. Lancaster et al., "Evaluation of a Laser Scanner for Shape Sensing BKN Amputees", RESNA 12th Annual Conference, New Orleans, Louisiana, pp. 155-156, 1989.
Barlow John
Ferguson Jr. Gerald J.
Robinson Eric J.
Vo Hien
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