Increased industrial use of composite materials for manufacturing strong lightweight components stimulates endeavours for more efficient assembly methods. This study attempted to find an optimal method to provide optical aid for the placement of pre-impregnated reinforcing fabric (prepregs). A novel approach to optical assistance for the placement of prepregs was designed to be straightforward and affordable. The developed system meets industry standards for accuracy, and provides the solution at a cost many times less than existing solutions. The findings allow companies in the composite material industry to eliminate prepreg layup errors at an affordable price.

'n Toename in die gebruik van saamgestelde materiale vir vervaardiging van sterk, liggewig komponente stimuleer pogings vir meer effektiewe samestellingsmetodes. Die doel van hierdie studie was om 'n optimale metode te vind vir die optiese ondersteuning in die plasing van vooraf geïmpregneerde materiaal. 'n Nuwe benadering vir optiese ondersteuning vir die plasing van vooraf geïmpregneerde materiaal is ontwerp om bekostigbaar en eenvoudig te wees. Die ontwikkelde benadering voldoen aan die industrie se standaarde vir akkuraatheid, en bied die oplossing teen 'n prys wat aansienlik minder is as bestaande oplossings. Die bevindinge bied besighede in die saamgestelde materiaal industrie met 'n bekostigbare oplossing om vooraf impregnering plasing foute te elimineer.

PURPOSE: To design a simple, cost-effective system for gaining rapid and accurate calyceal access during percutaneous nephrolithotomy (PCNL). MATERIALS AND METHODS: The design consists of a low-cost, light-weight, portable mechanical gantry with a needle guiding device. Using C-arm fluoroscopy, two images of the contrast-filled renal collecting system are obtained: at 0-degrees (perpendicular to the kidney) and 20-degrees. These images are relayed to a laptop computer containing the software and graphic user interface for selecting the targeted calyx. The software provides numerical settings for the 3 axes of the gantry, which are used to position the needle guiding device. The needle is advanced through the guide to the depth calculated by the software, thus puncturing the targeted calyx. Testing of the system was performed on 2 target types: 1) radiolucent plastic tubes the approximate size of a renal calyx (5 or 10 mm in diameter, 30 mm in length); and 2) foam-occluded, contrast-filled porcine kidneys. RESULTS: Tests using target type 1 with 10 mm diameter (n = 14) and 5 mm diameter (n = 7) tubes resulted in a 100% targeting success rate, with a mean procedure duration of 10 minutes. Tests using target type 2 (n = 2) were both successful, with accurate puncturing of the selected renal calyx, and a mean procedure duration of 15 minutes. CONCLUSIONS: The mechanical gantry system described in this paper is low-cost, portable, light-weight, and simple to set up and operate. C-arm fluoroscopy is limited to two images, thus reducing radiation exposure significantly. Testing of the system showed an extremely high degree of accuracy in gaining precise access to a targeted renal calyx.

The current development of the rapid prototyping industry in South Africa is characterised by the strong dominance and fast growth in sales of three dimensional printers. Although it reflects the international trend, it seems that the industrial community lacks a clear appreciation of the real strength of this technology, especially with respect to the large variety of devices available today on the market. This paper surveys the current state and capabilities of three dimensional printing (3DP). Based on its technical background - the ink-jet printing known from the printer and plotter industry - a classification structure is developed and proposed. Different printing techniques and process concepts, together with their advantages and limitations, are described and analysed. Typical examples from three completely different application areas - manufacturing, medicine, and architecture - are presented and discussed. Some basic considerations for an informed selection of the right technology for a particular application are then presented.

Sterk groei in die verkope van drie dimensionele drukkers (3DP) kenmerk die onlangse groei in die snelle prototipe industrie in Suid-Afrika. Ten spyte daarvan dat hierdie 'n internasionale tendens reflekteer, blyk dit dat die werklike waarde van die tegnologie nog nie ten volle waardeer word in die industriële gemeenskap nie, veral aangesien daar so 'n groot verskeidenheid masjiene in die mark beskikbaar is. 'n Oorsig oor die huidige stand en vermoë van drie dimensionele drukkers word hier gegee. 'n Klassifikasiestruktuur - gebaseer op die inkspuitdrukkertegnologie - word ontwikkel en voorgestel. Verskillende druktegnieke en konsepprosesse word ontleed. Daar word ook gekyk na die voor- en nadele hiervan. Tipiese voorbeelde van drie verskillende toepassings (vervaardiging, medies, en argitektuur) word aangebied en bespreek. Basiese riglyne vir 'n ingeligte keuse van die regte tegnologie vir 'n spesifieke toepassing word ook gegee.