## 2 The Grimstad Experiment--Site Specifications  
The experiment was conducted at the Grimstad campus of the University of Agder, Southern Norway, over a ten-day period. Due to practical and logistical considerations, such as the length of power and control cables and the motion platform not being certified for outdoor operation, in particular in rain, the test site had to be located near the laboratory building of the University. This building is approximately nine meters in height, and the motion platform was located approximately ten meters west of it, with the reference lidars located approximately five meters further west (see Figure 1). The overall topography of the site at the university campus is relatively flat within a radius of one kilometer, with the sea to the South and East and some more hilly terrain towards the West (Figure 2).  
Two types of lidar wind profilers, a pulsed system, WindCube V1 (manufactured by Leosphere, France), and a CW system, ZephIR 300 (manufactured by Natural Power, Malvern, UK), were deployed in the experiment. One instrument of each type was mounted on a motion platform (hereafter referred to as moving lidars) and exposed to several controlled motion patterns with constant frequency \(f_{0}\) and amplitude \(A_{0}\). The motion platform used at this experiment was a 6-DOF E-motion 1500 Motion System (manufactured by Bosch Rexroth, Boxtel, Netherlands). Two corresponding fixed reference lidar systems were located at a distance of 5 m from the platform. The coordinates of the lidars were defined such that the X axis was pointing south, the Y-axis was pointing west, and the Z-axis was pointing down.  
The experiment began on 2011-08-16 at 15:50 and ended on 2011-08-25 at 17:50 UTC. A total of 55 test cases were applied to the lidars to investigate the effect of various motion types on the lidars' performance (including roll, pitch, yaw, heave, and surge in addition to combined motions, see Table 1). The number of test cases was primarily determined by the availability of the motion platform, which was limited to a two-week period. During this time, the objective was to conduct a comprehensive series of tests that included both individual and combined motion scenarios to systematically investigate the effects of motion on lidar systems. Furthermore, each motion scenario was sustained for a sufficient duration (typically three hours) to ensure a robust statistical analysis.  
For each test case, the lidars on the moving platform were subjected to a specific motion. Throughout the experiment, the moving lidars were kept stationary during nighttime to allow for a baseline comparison of the systems in non-moving conditions. As reported in the experiment log, some of the baseline test cases were ineffective because of either a lack of data or a malfunctioning lidar at the time of the baseline tests (tests 7, 18 and 30); thus, these tests have been discarded from the analysis.  
Figure 1: Lidars on the moving platform. A WindCube V1 and a ZephIR 300 were mounted on a moving Hexapod; reference lidars were placed 5 m west of the moving ones.  
The lidars were set to measure wind speed up to 200 m above the surface at 10 different heights. Table 1 shows the height settings for the four lidars during tests 1 to 10. As a correction for the difference in height between the neutral position of the motion platform mounting plate and the ground, a 3 m offset has been subtracted from the height setting of the moving lidars. WindCube V1 demonstrated the best signal levels and accuracy at about 85 m. Hence, from test 11, ZephIR 300 lidars were configured to measure at 85 m eight times, at 45 m once, and at 145 m once for a more reliable statistical basis at 85 m (see Table 2). Therefore, in this study, the data will be evaluated at 85 m and also 145 m as a reference height for modern wind turbines. The motion data were recorded by a six-DOF Cross-Box--NAV440 inertial measurement unit (IMU).