3.2.2. Experimental procedures

The simulated pipeline trajectory is similar to the one shown in Figure 2. The outer, middle, and inner table rotation axes are operated to accomplish the PIG attitude angles changes. Specifically, the rotation of table inner axis indicates that when PIG runs in the pipeline, it would experience varying degrees of rolling motion. The table middle axis could simulate the changes of pitch, and

Figure 3. Crossbow IMU300CC and 2103HT table.

the PIG azimuth angle variations are simulated by table outer axis. The experiment is designed by as the following:

Firstly, the table rotates around the middle axis for 90˜ to make the PIG in horizontal plane as shown in right panel of Figure 3, which simulates the PIG launcher stage for pipeline inspection, and keeps this position for a few minutes to complete the initial alignment.

