Relative Velocity and Acceleration with Translating and Rotating Frames  (continued)

 

 

Since  u  is a unit vector      d(u)/dt  =  ω x u     and     rAB  d(u)/dt  =  ω x rAB  u   =  ω x rAB  

 

          ω x rAB  =  vAB    is the velocity of point B with respect to point A in the fixed frame, F

 

 

The relative velocity equation becomes:

 

 

 

         vB  =    vA  + vB|1  +  vAB    =    vA + vB|1  +  ω x rAB 

 

 

 

 

Definition of terms:

 

where    vB  is the velocity of point B in the fixed frame, F

 

               vA is the velocity of point A in the fixed frame, F

 

             vB|1  is the velocity of B in the x1y1 frame (body fixed frame of reference)

 

             vAB is the velocity of B with respect to A in the fixed frame, F

 

              ω  is the angular velocity of body 1 in the fixed frame, F

 

             rAB is the position vector  from  A to B

 

 

 

Note:                vAB =  ω x rAB  and  rAB

 

 

Click here for examples.               Click here to continue with discussion on acceleration.

 

 

 



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