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 Kinematics and Dynamics Kinematics and Dynamics Physics Help Forum Jan 26th 2011, 01:11 PM #1 Junior Member   Join Date: Jan 2011 Posts: 4 Position/Motion Vector Getting a future position Hi, I am currently reading a paper where its necessary to know the position of a node at a future time. A node will know its current (x,y) position, its previous (x,y) position one second ago and will know its current speed. Code: The paper says the following: v(I,T): motion vector of a node I at time T p(I,T): position vector of node I at time T It gives the following relationship: p(I,Tc)=p(I,Tr) + v(I,Tr).(Tc-Tr) where Tr is a past time, Tc is the current time  (This is basically the distance=speed*time formula from what I can see with the distance added to the (x,y) coordinates). Part of the algorithm says that a node should predict the position of another node at time Tc + Δt, where Δt is a small time like 1s, if it knows the nodes current position and motion vector. It says it relies on the accuracy of the motion vector and then says the following: Code: Let m denote the motion vector directly accessed from GPS. Mold and Mnew are the reported motion vectors at the last time and this time respectively. Mnew = alpha*Mold + (1  alpha)*m, 0<=alpha<=1 Alpha=0.3 if the node is in the area of a junction, 0.7 otherwise  I am a programmer and dont understand fully what information I should actually store in the motion vector and still dont understand how given a nodes (x,y) position and speed at time Tc, I can work out its position at time Tc + 1 given that it could have moved in any direction? Can somebody please outline as simply as possible how I can get this future value? I am quite stuck so any help appreciated. Many thanks in advance.  Tags future, position, position or motion, vector Thread Tools Show Printable Version Email this Page Display Modes Linear Mode Switch to Hybrid Mode Switch to Threaded Mode Similar Physics Forum Discussions Thread Thread Starter Forum Replies Last Post ling233 Waves and Sound 0 Aug 11th 2014 08:39 AM yungman Advanced Electricity and Magnetism 4 May 5th 2011 10:33 AM quantum_enhanced General Physics 1 Sep 26th 2010 04:46 AM ohm Kinematics and Dynamics 4 Aug 18th 2010 06:31 AM christina Kinematics and Dynamics 4 Dec 8th 2009 08:59 AM 