Robert,
I can only assume you're trying to tell me that you're an aerospace
professor somewhere, who has unspecified experience designing rockets in
industry. Given your frequent insistence that the best way to attain low
launch costs is to use unpaid student labor, this only concerns me more.
DH, That's the best description I've heard of the BPS system. I wonder if
it's still accurate to model the controls as a torque from the gimbal
instead of as aerodynamic forces from an "effective" AoA
On Sat, Mar 3, 2018 at 9:22 PM William Claybaugh <wclaybaugh2@xxxxxxxxx>
wrote:
Clever....
Bill
On Sat, Mar 3, 2018 at 7:16 PM DH Barr <dhbarr@xxxxxxxxx> wrote:
For commercial high end hobby solids it's probably more useful to think
about it as wiggling the nose rather than gimballing the motor. I'm not
aware of any write-ups in this regard.
On Mar 3, 2018 8:43 PM, "Charlie Garcia" <dragonrider.hhcc@xxxxxxxxx>
wrote:
Robert,
Joe is building low power rockets for a reason. The design doesn't scale
and Joe will tell you the same. It actually has nothing to do with speed
though. You won't hit Mach 3 if you have a motor less than 1/3 of your
airframe diameter.
Any University using solids in a rocket like you propose would have a
wide set of engineering solutions to choose for control. A BPS style gimbal
would not be one of them. Since you're so inclined to call University
groups and hobbyists green, perhaps you'd regale us with tales of your
launches.
Charlie Garcia
On Sat, Mar 3, 2018, 8:35 PM Robert Clark <rgregoryclark@xxxxxxxxx>
wrote:
What I was wondering is if the methods used by BPS.Space would still
work when the rocket is traveling at supersonic speeds. They are rather
green:
https://www.youtube.com/watch?v=u-86tsFJ7lE
<https://m.youtube.com/watch?v=u-86tsFJ7lE>
About the gimbled nozzles, university teams trying to produce one
would have the advantage of knowing what was already done and trying to
reproduce what has already worked.
Bob Clark
On Saturday, March 3, 2018, Henry Spencer <hspencer@xxxxxxxxxxxxx>
wrote:
On Sat, 3 Mar 2018, Robert Clark wrote:
The method likely could be modified to gimbal a movable nozzle only
as is
done with large solids.
Not easily or cheaply. The hot-gas seals used in the nozzle gimbals
for the big solids were a considerable technological achievement, and took
quite a while to develop, which is why a bunch of other vectoring methods
were used in the early days of big solids.
A big question though is whether the method would
work for rockets at supersonic speeds.
Since it's been used for ICBMs and orbital launchers for many years,
there is little doubt of that.
Henry
