TVL₁ Planarity Regularization for 3D Shape Approximation

The modern emergence of automation in many industries has given impetus to extensive research into mobile robotics. Novel perception technologies now enable cars to drive autonomously, tractors to till a field automatically and underwater robots to construct pipelines. An essential requirement to facilitate both perception and autonomous navigation is the analysis of the 3D environment using sensors like laser scanners or stereo cameras. 3D sensors generate a very large number of 3D data points when sampling object shapes within an environment, but crucially do not provide any intrinsic information about the environment which the robots operate within. This work focuses on the fundamental task of 3D shape reconstruction and modelling from 3D point clouds. The novelty lies in the representation of surfaces by algebraic functions having limited support, which enables the extraction of smooth consistent implicit shapes from noisy samples with a heterogeneous density. The minimization of total variation of second differential degree makes it possible to enforce planar surfaces which often occur in man-made environments. Applying the new technique means that less accurate, low-cost 3D sensors can be employed without sacrificing the 3D shape reconstruction accuracy

Improving Geoidal Height Estimates from Global Geopotential Model Using Regression Model and GPS Data

Conventionally, for most application, position of a point is often referred to the geoid as the reference surface. Thus there is an important need for the knowledge of the geoid undulation in the area where positioning tasks is performed, This requirement is made more apparent with the advent of high precision using GPS where the resulting ellipsoid height must be converted to orthometric height. An ideal solution is to use a precise gravimetric solution where the geoidal height at each GPS point is computed and applied. Unfortunately, at the moment there is no such solution available in Malaysia. However. efforts are currently being made to develop a precise gravimetric geoid, For the time being, an alternative method would have to be use and the global geopotential model is one of them. [n order to increase the accuracy of computed geoid height from the geopotential model. a regression model is used in conjunction with the GPS data. The resulting accuracy estimates of the geoid height determination increases from around 60 cm 'to about 10 cm leve1