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Old 04-24-19, 03:06 AM   #12
ljqcn101
Sailor man
 
Join Date: Jan 2013
Location: Hong Kong
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Quote:
Originally Posted by geosub1978 View Post
I am currently working on a method based on radial speed rule
(Bearing Rate=(Target Speed*sinAOB-Ownspeed*sin(LeadingAngle))/Range)

By taking into consideration that the new AOB=PREVIOUSAOB+BEARINGCHANGE

Then if you apply the Rule of Sins for three individual bearing shootings and counting manualy the bearing rate, you can have a final equation with an unkown target speed or sinAOB. The maths are too long for the moment and require patience!
Great. But be careful when computing with Ownspeed, since you need a course change in order to get a single solution, if you keep a constant ownspeed.

For computational convenience the boat is always assumed to be able to instantaneously change speed or course at each observation point, but in reality it cannot. And any departure from these idealisations introduce errors. That's why I use distance and direction between two observation points for computation.
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