Despite all modern techniques in registering terrestrial laser scanner point clouds, registration of
multiple scan positions is still a crucial issue, especially in large projects. Processes like the
detection of corresponding points in scans and placing targets in fields consume a lot of effort,
time and money. Three points are the minimum number of common points required for
registration. In this work, a new two points registration (TPR) algorithm is developed to register
terrestrial laser scanner point clouds using only two common points automatically. Decreasing
the number of the required common points to two points reduces one-third of the registration
work in both field and laboratory. An accuracy assessment study is then performed to compare
the registration accuracy of the developed algorithm and the traditional algorithm employing
both the time of flight laser scanner and the phase shift one. The results show that the accuracy
of the two algorithms is approximately equal within the considered point clouds accuracy in both
cases.