Geodesy

1.1 The ‘Free Adjustment’ also known as the ‘Inner Constraint Adjustment’, has no control station in network. All the stations in the network are allowed to move and the final coordinates are derived from Least Squares Adjustment. This method has the maximum degree of freedom and is commonly used to check the internal consistency of the network. For this to work all the adjustment data must be of the same or similar precision. Since this adjustment allows a check on the internal consistency of the network it is only necessary to perform the adjustment once. Like most least square adjustments, it can invoke one or multiple iterations.

1.2 The ‘Minimally Constrained Adjustment’ has only one control station in network. All of the stations, except the control point, in the network are allowed to move and the final coordinates are derived from a Least Squares Adjustment. It is either completely fixed to the control coordinates or is allowed to move according to the settings, depending on the settings of the standard deviations of the control station. This method is also commonly used to check the internal consistency of the network. Once again since this adjustment allows to check the internal consistency of the network, it is only necessary to perform the adjustment once. Again, like most least square adjustments, it can invoke one or multiple iterations.

1.3 The ‘Constrained Adjustment’ has at least two control stations. All the stations, except the control stations, in the network are allowed to move and the final coordinates are derived from a Least Squares Adjustment. It is either completely fixed to the control coordinates or allows a move according to the settings, depending on the settings of the standard deviations of the control stations. This method has the least number of degree of freedom. Since the ‘Constrained Adjustment’ requires at least two control stations in the network, this type of adjustment is not used to check the internal consistency of...