Saturday, January 20, 2007, 10:59 AM
Since the basic valve actuation and sensor monitoring setup is working, we have started coding the automated nominal and safety sequences. The propulsion team has re-assembled the plumbing system, so this week we reverified the functionality of the valves and the ASA command computer. We also have been developing a system test control pages to simplify the plumbing and control system testing which will occur in two weeks.
Some of the computer engineering team crossed department lines this week and helped the propulsion team reassemble the plumbing hardware, speeding up the process. Both teams will be working as an integrated unit in the coming weeks, so it is good to see the students working together.
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Tuesday, December 12, 2006, 12:39 PM
Much work over the last few weeks. The computer team has been aggressive with finishing off the control logic in LabVIEW and the required wiring from the Tanks and Motor assemblies to our primary computer controller (looks like we may need more memory on the computer, will look for donations).
Since the propulsion team is finishing up the plumbing work that gives us the ability to start testing the connections to our sensors and more importantly to test our valve controls. Specific work on the control logic included:
- Countdown: This LabVIEW subVI (i.e. subroutine) executes the firing countdown logic
- Notification: This subVI allows us to send and log messages which are viewed on our monitor computers
- Data Server Writer: This subVI is responsible for writing all sensor valves to our data server which is used to transmit data to our monitoring workstations.
- Monitoring: This subVI performs all limit sensing on the sensors. If any sensor value goes out of limits a flag is set which is used in other part of the control logic
- Need to complete: Ignitor startup, main valve control, shutdown/purge logic
Hardware-wise our status includes:
Tank side: Pressure sensors all connected and tested, Thermocouples connected and tested
Motor side: Pressure sensors connected at the terminal block, Still to do: Thermocouple connections, Strain gage connection, Accelerometer connection
Commanding: Cabling 75% complete, need to hook up remaining valves
Things we learned in LabVIEW:
- Opening connection to the Data Server once, otherwise the Writing VI opens/writes/closes each instance which is very time consuming
- Issue with respect to calibration with LabVIEW solved. The min/max values needs to be the min/max after calibration and not the min/max of the raw input
Assisted the motor team with ablative test setup
- We tested a thermocouple to its limit, the outer casing of the thermocouple popped at ~2000 degrees F. However the thermocouple still works fine.
In January we will be doing cold-flow testing. This means moving our setup out to some test location. We will need a generator. We are going to have to find some funding for that.
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Saturday, November 11, 2006, 08:50 PM
The propulsion team is nearing completion of the plumbing and mounting of our sensors so we're getting closer to the time where we can do our final wiring. A lot of work has been done over the last two weeks.
- Validated/tested that the load cell works properly. We drove 3 different vehicles on top of the load cell. Readings were in the range expected. The previous weeks test did not properly isolate the load cell from the ground (i.e. the ground absorbed some of the load)
- We had to rework our displays since the configuration of our system has changed. We are not using redundant sensors in a lot of cases.
o Completed the motor display re-work
o Completed the plumbing display re-work
- Reworked the DAQ setup in LabVIEW
- Completed the ignitor/thermocouple test. Results showed instantaneous change in temperature. This ensures us that we will know the ignitor is lit and that we're go for main valve opening
- Added the 3 analog input parameters to handle monitoring of 12/24/28Vdc power sources
- Began work on the automated firing sequencer
- Identified wire colors for pin locations for both 25 pin wire bundles. Also secured both to the test stand
- Hooked up one thermocouple to a wire bundle on the tank stand.
- Began labeling wire measurement locations
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