Final Design:

The final design consists of 5 separate sub systems. Imaging, communications, thermal, motion control and other mechanics. The imaging system uses a Texas instruments TI6416 DSP and D3 engineering's camera kit. This system makes up the brains as the TI6416 is the master processor in the system. The camera measures the reflection density of the samples and is also used for wetness detection and slide detection. The communications are done with an Motorola 8051 based controller as a hub. This controller takes I2C messages from the TI6416 and commands the twp 243 motion control boards. The motion control is done with 4 stepper motors. Two have drive belts to control the Y movement of the metering tower and the camera. One is linear actuated to control the Z-movement of the metering tower and the last is used to aspirate and dispense fluid using the fluid pump. Thermal control is achieved using 12 heating elements and 12 thermistors for feedback. Everything is combined using high precision steel rails that allow fluid movement of all axes. The tower is manufactured of high grade nylon for construction and sterilization reasons. The chamber is made of aluminum for its heat transfer properties. The proof of design test is done by completing 12 test of the same sample and comparing the standard deviation.