You can use arbitrary objects such as cylinders or boxes as bones, controlling their animation as if they were bones in a bones system. You can apply an IK solver to the boned objects.
To use objects as bones, select them and then turn on the Bone On toggle on the Object Properties rollout of the Bone Tools dialog.
Once you've set objects to function as bones, applying an IK solution behaves as it does for standard bone objects. The geometry of the boned objects can stretch or squash during animation.
 Link the objects you want to display as bones.
 Link the objects you want to display as bones.
                Select all of these objects.
 Select all of these objects.
                  
                Bone Tools.
 Bone Tools.
                  
                Select the object to use as the start of the IK chain.
 Select the object to use as the start of the IK chain.
                IK Solvers
 IK Solvers  HI Solver.
 HI Solver.
                  You can choose a different IK solver, but the HI Solver is the preferred choice.
Now when you transform the boned objects, their movement is governed by the IK solver.