Apologies if this is a bit off-topic as this is neither un-manned nor aerial, but I've seen a few posts about underwater navigation. My goal is to know where a diver has been while underwater - ideally to within 10-15m over a 45-60minute dive - I'm wondering if there is any scope for using a cheap IMU. The start position can come from a GPS but the signal will be lost as soon as the diver submerges. Depth is relatively straightforward to measure but x and y position will have to rely on dead-reckoning - is this feasible? How much is the position fixing likely to drift over the course of the dive and how much of this can be corrected by knowing the re-surfacing postion - when the GPS re-connects?
Thanks in advance
Peter
Replies
Peter,
head over to http://openrov.com/forum the problem is IMU drift rate over time without GPS to reset the IMU gyros there is talk of short base line chirp beacon array scaled to "hobby size and $ " but both short and long baseline has been in use for decades .