05 April 2009
Another successful deployment flight!
06 Apr 09 20:22
As the weeks are running out, team MADS is still in high gear! After our last deployment test on March 18th, the team ran into a fair amount of stumbling blocks--IE not all the planes would deploy. After hours of talking to the manufacturer and testing and disassembling the actuators is came down to our mounting design. We compressed the actuators, squishing pins and nylon gears within them. This resulted in the actuators pulling about 25% of their spec force. After realizing what had been done, we took apart all the actuators and fixed them. Now they pull exactly what they should!
Because out mounting design was flawed, we re-designed and fabricated mounts over last week with hints from the manufacturer. The actuators were re-tested with these new mounts and still pulled their quoted amount. (Hurrah!)
The time came to do a vibration test and during the fixing process on the actuators, CA glue accidently glued the ribbon cable down to the plastic internally to the actuator--meaning if this shakes around, there is no room for the cable to wiggle, therefore the cable can break. And this happened. We broke one of the cables, but Michael fixed it up and everything was good to go!
The next deployment test came up this last weekend. There was an issue with the transmitter on the CUPIC-powered sub-vehicle not having the right exponential settings which resulted in the plane crashing and the GPS antenna coax cable tore--deployments would have to happen without an autonomous sub-vehicle (sad, but we can still deploy!).
The goal was to get 4 deployments during a single flight. The first flight, 3 SVs deploy successfully, but the 4th failed. On the second flight, the same thing happened. This is not a failure, but a success because we have proven that deployment is a difficult task to make reliable. We showed our re-design was more reliable than our original design and we are in the process of debugging the failed deployments. It is also a success that our deployment-mechanism design works great in failed deployment conditions. With the pins partially pulled, the SV stays constrained in the mechanism!
This week we will be debugging the failed deployments and if we can fix anything that may have gone wrong, the autonomous deployment sequence will be tested, spring final review will be compiled, and we will present to Mike Griffin on Thursday!
Because out mounting design was flawed, we re-designed and fabricated mounts over last week with hints from the manufacturer. The actuators were re-tested with these new mounts and still pulled their quoted amount. (Hurrah!)
The time came to do a vibration test and during the fixing process on the actuators, CA glue accidently glued the ribbon cable down to the plastic internally to the actuator--meaning if this shakes around, there is no room for the cable to wiggle, therefore the cable can break. And this happened. We broke one of the cables, but Michael fixed it up and everything was good to go!
The next deployment test came up this last weekend. There was an issue with the transmitter on the CUPIC-powered sub-vehicle not having the right exponential settings which resulted in the plane crashing and the GPS antenna coax cable tore--deployments would have to happen without an autonomous sub-vehicle (sad, but we can still deploy!).
The goal was to get 4 deployments during a single flight. The first flight, 3 SVs deploy successfully, but the 4th failed. On the second flight, the same thing happened. This is not a failure, but a success because we have proven that deployment is a difficult task to make reliable. We showed our re-design was more reliable than our original design and we are in the process of debugging the failed deployments. It is also a success that our deployment-mechanism design works great in failed deployment conditions. With the pins partially pulled, the SV stays constrained in the mechanism!
This week we will be debugging the failed deployments and if we can fix anything that may have gone wrong, the autonomous deployment sequence will be tested, spring final review will be compiled, and we will present to Mike Griffin on Thursday!