Before revision:  We propose different update strategies for the grid points , where the approximation is valid to consider the locality of the planar approximation . We experimentally validate the approach by tracking the surface with a robotic manipulator.
After revision:  We propose different update strategies for the grid points , where the approximation is valid to consider the locality of the planar approximation in combination with a projection method. The approach is experimentally validated by tracking the surface with a robotic manipulator.