Surveying adjustment datum and relative deformation accuracy analysis

First Experiences with the Deformation Analysis of a Large Dam Combining Laserscanning and High-accuracy Surveying

Monitoring the static and dynamic behaviour of large dams has always been a topic of great importance, due to the impact these structures have on the whole landscape where they are built. Many instruments and surveying methods have been applied so far in order to continuously access to the safety of this kind of huge structures. However, the common approach in a lot of developments has been foc...

Structural Deformation Surveying

Relative Bundle Adjustment

This report derives a relative objective function for bundle adjustment – driven by the desire for a truly large scale simultaneous localization and mapping algorithm that can operate incrementally in constant time. It is precisely the choice of a single privileged coordinate frame that makes bundle adjustment expensive to solve. This is especially true during loop closures, when the single fra...

Adaptive relative bundle adjustment

It is well known that bundle adjustment is the optimal non-linear least-squares formulation of the simultaneous localization and mapping problem, in that its maximum likelihood form matches the definition of the Cramer Rao Lower Bound. Unfortunately, computing the ML solution is often prohibitively expensive – this is especially true during loop closures, which often necessitate adjusting all p...

Network Adjustment Issues Using Mixed GPS Surveying Techniques

Modern GPS carrier phase-based survey techniques such as "rapid static" and "stop & go" are fast becoming the standard operational modes for building local geodetic control networks or for the densification of an existing network. However, such techniques do have some challenges when used together within a single survey project. For example, these mixed-mode GPS surveys do result in incompatibl...