Customizer Colorimeter/Nephelometer Case v0.1

thingiverse

This is a customizable case for a colorimeter/nephelometer that supports multiple straight signal paths (two to four). Each signal path can support one or more sources and/or sensors, increasing the number of colorimetric methods that can be performed. The case also permits source and sensor to be oriented at an angle to each other, making possible other analysis methods such as nephelometry. The cuvette holder can accomodate cuvettes up to 25.4mm in diameter and the holder is exchangable in the case - a single case can be used with different cuvettes. Several parameters, including cuvette dimensions and shape and number of signal paths, are exposed in the Customizer. Instructions Signal half path sets the distance from the sensor or source to the center of the cuvette. Signal paths defines the shape of the case; 2 paths yields a square prism, 3 a hexagonal prism, etc. Board dimensions are for the PCB/proto board that the sensors and sources will be mounted to. Standoff is the distance from the interior wall of the case to the back of the PCB/proto boards. If hemispherical bottom is set to one, the cuvette holder will have a hemispherical bottom fitting the cuvette. If set to zero, the holder bottom will be flat. Analysis depth sets the case interior height and represents the length of cuvette inside the case in the analysis volume. Relief for a ribbon cable is located at the top of one exterior wall for communication between the sources and sensors and the microcontroller. A wire chase is also provided for inter-chamber wiring. PCB boards are held in place by keepers along each wall and then kept in place by the lid. M3 fasteners hold the lid and case together; M3 nut traps are built in to the case. As a start, the electronics from http://www.thingiverse.com/thing:45443 can be employed.