For the work period between March 9 - March 23, the team’s goal was to complete Milestone 5, which is the fabrication milestone of the project. The team had previously begun the task of ordering and acquiring parts for the chamber. As of now, the team has acquired all parts for the chamber except for the gas storage bags, due to the price of the bags. Currently, the team is having discussions with Dr. Song about reimbursement in the event the team has to purchase the gas bags out of pocket. More specifically, Dr. Song has been processing reimbursements for previous purchases, but the team has yet to receive any financial compensation so far. The team wants to continue mitigating out of pocket purchases by seeing if the promised NOV funding can be used. Unfortunately, Dr. Song has notified the team that a check from NOV has not been received yet. If needed, the team is prepared to split up the rest of the purchases, totaling around $150, and waiting for the reimbursement. 

     Another major task that was completed during this work period was the completion of chamber fabrication and the chamber prototype was delivered to the team on March 18th. Figures 1 through 3 show the testing chamber from different views. Since picking up the chamber from the machinist, the team has started placing the measurement devices inside the chamber in their predetermined locations. Furthermore, the chamber has been examined to make sure all components fit such as the thermocouples, gas sensor, and the electromagnetic lock. The thermocouples do fit through the four 0.3” holes placed in the back of the chamber and allow adequate room for more wires to be passed through. Moreover, the electromagnetic lock was tested and does work as intended. When the lock is turned off, the door can be easily opened and when it is on, the door does not move at all. This is a good sign and shows that the validation test for the lock will provide the expected results. Figure 4 shows where the magnet for the lock is placed in the chamber and where the locking plate is placed on the inside of the door. Figure 5 shows the relay switch and how it is connected to the lock and the microcontroller. This allows for the magnet to activate when the temperature surpasses 100 ℃ and deactivate when temperatures decrease. Only one problem occurred with the lock, when the lock turns on, the door must be compressed slightly for the magnet to catch on the locking plate. One solution for this will be to create a simple latching mechanism that keeps the door in tension even when it is unlocked.

     Unfortunately, the gas sensor will need extra hardware if the team wants to place it inside the chamber. The 4 pin grove cable that is used to connect the gas sensor to the digital display it too big to fit in the holes placed at the back of the chamber. This is because the female to female connection ends are too large to be placed through the holes. To mitigate this issue, another 4 pin grove cable will need to be purchased to allow for smaller jumper cables to be used to pass through the chamber holes. A cheaper alternative will be to alter the plastic housing around the connection points to make them slimmer to pass through.

     Technically, the team has not finished Milestone 5, but seeing as the only remaining task for that milestone is to order and acquire the gas storage bags, team 20 has begun to shift its focus toward Milestone 6, validation testing. Overall, the finalization of milestone 5 will come down to dedicating enough time to make additions to the testing chamber such as the insulation for example. This will also allow the team to find out any problems along the way and troubleshoot them as needed.