The last project of my undergraduate life was an industrial embedded system. Wabco, a major hydraulic system manufacturer, wanted a system that would continuously monitor a testing rig. Testing rigs are those machines that they use to test the hydraulics and this involves pressure and temperature parameters. The system should be able to monitor these parameters for sustained periods of time (24X7). The operator is required to give lower and higher threshold values for each parameter at the start of a testing cycle and then the system measures the parameters to see if they are within the 2 thresholds. If not, then there is an abnormality and in the event of any abnormality, the system should report it to the operator through a SMS and stop the rig. For completeness, the board has a display that sequentially displays the parameter values. The embedded system is designed to handle 6 pressure values from 6 pressure transducers and 2 temperatures from K-type thermocouples.
A major feature of the board is an indigenous solution to a local problem we have in Tamil Nadu – power cuts. The board is designed to detect these power cuts and intimate the operator and when the power resumes, the rig is automatically restarted without manual intervention – automation.
The major components of my design were an MSP430G2553 microcontroller (for central processing), an ATMega16 microcontroller (to provide display data for the 7 segment displays through IC7447 decoders), a GSM module interface (to send the SMS), a MAX4617 multiplexer (to channel the 8 sensor values), a relay (works in tandem with the rig’s control switch to stop or start it) and on-board power regulators for the power supply. After the schematic development, PCB layout & manufacture and assembly of components – the result is:
The embedded system’s top side (above) and the bottom side (below)
For ‘industrial reasons’, I wasn’t allowed to take my phone to record the video of the board working with the rig, but here is the next best video I have – the testing of the board with 1 pressure and 1 temperature monitoring.
The curious thing about doing an industrial project is preparing and analyzing FMEA – Failure Mode and Effect Analysis to evaluate the performance of the system. This is my FMEA for the Unmanned Rig