Mail to Robert DeHate
The sustainer will use dual deployment. For this I will
use Roctronics. I will also add some sort of redundancy.
I have concidered
a MAD for backup.
I want it to check itself for safe conditions before
lighting the sustainer.
Here is a flow chart of how I would like it to work. If you see any mods that will make it better let me know.
I could not find a reasonable source for the magnetic sensors so I may just use the accelerometer to detect motor burn out.
The Terrier has a deployment electronics bay that I installed. I have not
mounted anything in it yet. It will be used as either a backup to motor ejection
or as main deployment if I use a hybrid motor.
I was concidering using a
magnetic apogee sensor but I dont know if the metal tank from the hybrid motor
will effect it at all. Also I have the two threaded rods running down the inside
of the airframe right past the electronics mounting board. The biggest issue is
that there is very little room in there between the MMT and BT. Also I have not
decided on how to mount the ejection charge.
The Sandhawk has two electronics bays. The lower bay is just above the fins between the MMT and BT. It will holde the electronics for sustainer ignition. I will be using my "Simple Alt" modified by removing some of the connectors so that it would fit in the space between the 54mm MMT and the 4in BT.
The second electronics bay is built into two couplers that were joined by a 4in piece of BT. This gives me 12 in of room for mounting electronics. It has the typical arrangement of having the charges mounted to the bulkheads so the main and drogue are on opposite ends. I have made a harness board that will mount two roctronics controllers with thier sensor boards. These will work together to deploy the chutes. The Master will be in charge of deployment. The slave will monitor the depoyment to verify it is successfull. It will deploy the chutes if the Master fails to deploy them within 1 second of Main/Apogee events. I will also install my R/C backup circuit that will allow me to remotely deploy the main chute if all else fails.