How about doing periodic GPS nav, and using inertial navigation in the interim. If you can tolerate the accumlated errors between GPS fixes, might be a way to go. Accelerometers are getting small and cheap. > tiresome though ;-) I'm afraid he's going to have to let this one go > > -- > http://www.piclist.com hint: To leave the PICList > mailto:piclist-unsubscribe-request@mitvma.mit.edu > > -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads