On Mon, 2004-05-03 at 11:28, John Carmack wrote: > The last two vehicles have been continuously variable differential > steering. The difficulty with that over solenoid operation is that > solenoids give you instant response, where you can go from full on to full > of in 10 msec at the actuator, while the ball valve driven big engines take > 800 msec to go full open to full close. Even though you have the same > amount of control authority with each engine supporting 1/4 of the vehicle, > the responsiveness is much lower.
OK. Makes sense. > The decision is a no-brainer if you have more complex engines, like our > mixed monoprops or a biprop. I'm not so sure about that. It will have a lot to do with the flow temperatures and heat flux at the vanes. Although, I suppose the expansion cooling would be enough even in a hot bi-prop. > For 90% peroxide it is less clear cut, but I > still think there are compelling advantages. If the KISS engine weren't so thirsty and the POGO frame already built (without a place to put a center engine) I'd give it a try. I am thinking of adding a gimble to the POGO engines - It won't help the cross coupling issues at all, but otherwise seems to have the advantages of vanes. You've just about got me convinced. Thanks, Dave -- David Masten <[EMAIL PROTECTED]> _______________________________________________ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list
