About founctions of kinematic

[Dane Lee]

In the first model, use setloc(),Visualtool go down 1m, then it can back to original position; but use addkinematic(),Visualtool9 can't back to original position in the second model.
In the second model,the code in OnEntry:
double endtime=addkinematic(label(stamp,"kinematics"),0,0 ,-1,1,0,0,0,0,time(),KINEMATIC_TRAVEL);
addkinematic(label(stamp,"kinematics"),0,0,1,1,0,0 ,0,0,time()+endtime,KINEMATIC_TRAVEL);
I think that the distance of it travel down double it travel up.
Please,Tell me how the result of second model can be the same as first model,using addkinematic();
Help your reply,thanks!