Any product or practice can be improved. Rosscraft is responsive to scientists and health professionals. The Centurion Kit reflects a consensus of what is required for comprehensive anthropometry for individual and team deployment.
The Rosscraft line of Campbell calipers are named after the late Mr. Robert Campbell, the inventor of the double siding branch principle, an exclusive Rosscraft design feature under US patent No. 4265021. To our knowledge, it is the only caliper manufactured in the world that has long branches that do not bind under pressure at the tips.
Campbell 20 torso breadths such as acromial, transverse chest, biiliocristal, etc. are obtained with straight branches. AP Chest, and some head measurements are made using the AP Extension or Branch Pointers with olive tips. These are exactly 10 cm each (and can be calibrated using the adjustable screw and lock nut). Thus the caliper reading from AP branch tips will be 20 cm too large (easily corrected by subtracting 20 cm constant in the data entry program or spread sheet).
Campbell 10 small bone caliper, 18 cm, based on the sliding branch principle, has pressure plates 10 mm diameter that provide areas that encompasses the epicondyles.
Segmometer 4 for measuring lengths evolved from a prototype retractable carpenter or engineer’s tape for use in Nigeria by Dr. Linda Blade. We affixed cotter-pin pointers with rubber bands and 5-minute epoxy glue. We found that the rustic instrument was as good or better than the classical anthropometer for obtaining projected heights and direct segmental lengths. Another prototype was designed in Australia by the University of Western Australia and used in the Kinanthropometric Aquatic Sports Project. The Rosscraft models dispense with the housing using only a flexible tape, with precision machined base and slider indicators. Replicated measures in certification courses using the Rosscraft segmometer sets a new standard for precision.
Technical note: Care must be taken to wind the tape with the convex side in the inside of the coil, winding against the convex side may cause crimping. All new models with a flat base plate are read from the near edge of the slider for both direct and projected measures.
Head Square and Retractable Centimetre Tape. This is a portable, practical alternative to a stadiometer for measuring stature and sitting height. The headboard, consists of a horizontal plane and a triangle. A retractable metal centimetre tape is included with the Head Square. Techniques for orientation of the head, in the Frankfort plane, marking heights and measurement are fully described in Anthropometry Illustrated, Anthropometry Fundamentals and the Anthropometry Techniques DVD.
Tommy 3 small bone caliper, 15 cm, based on inverted “T” principle. It is an alternate instrument to the Campbell 10. (it replaces the popular entry level professional Tommy 2 caliper used extensively for somatotyping).
The Slim Guide skinfold caliper is an inexpensive alternative to the Harpenden caliper. It yields approximately similar results and its rugged ABS plastic construction, with high quality springs, guarantees a long life of usage. In the hands of a trained anthropometrist, skinfold calipers percent technical errors of measurement for a single replication as low as 5% depending on training and technique.
Rosscraft markets both calipers. The Rosscraft Slim Guide calipers are black with a silver scale. It is also available in white with a black scale. They have a similar dynamic action to calipers costing over fifteen times as much. Made from high impact ABS plastic, the Slim Guide can be dropped without damage. It is so indestructible we can ship in a manila envelope with no extra padding. The scale of 0 to 85 mm is especially useful in assessing skinfolds at the upper ranges, that are not accommodated by most other calipers. Accuracy may be interpolated to 0.5 mm. There are grants for quantity purchase of Slim Guides for courses and projects.
Anthropometric tape is a steel flexible tape with a filed notch and patch zero indicator to provide a better reading interface than a single zero line since the interface has no area. The notch helps orient the tape and align on the interface.
Technical note: in the preferred technique, the tape is always held in right hand by digits 4 and 5; digits 1 and 2 are the snubbers; digit 3 for pinning, leveling or and adjusting tape perpendicular to the long axis.
The scale on the obverse side is a diameter scale, the increments enlarge by 3.14... times the incremental circumference or linear scale values, e.g., 30.0 cm circumference girth is about 9.5 cm in diameter. The diameter scale has no apparent use in anthropometry as it has in the forest industry for assessing diameters of tree trunks and rolls of paper.