# Recovery Motion Analysis for False Ceiling Inspection Robot
## 2 Background
### Using Mobile Robotic Solutions for False Ceiling Inspection
A wheeled base provides the benefits of ease of operation and replacement if needed, along with a well-researched locomotion mode to work upon. The Mantis robot is a wall-climbing robot that detects surface defects and can work at heights due to its use of vertical adherence as a means of travel and mounting [36]. Its three-module design enables it to circumvent vertical support mullions along walls and can implement visual capabilities to inspect ceilings. However, it is limited to inspecting areas near walls due to its need for vertical mounting points for locomotion. Self-righting robots typically involve legged or bipedal robots, using the limbs as end-effectors to push themselves off a surface and flip themselves back to their neutral position to operate their intended movements and tasks again. This function is critical for robots working in complex environments [16, 37] to allow them to recover without external help in constrained areas. Some studies regarding self-righting involve multi-legged robots [38, 39]. Other research works take inspiration from nature [37], utilising an additional tail effector [17, 18]or wing effectors [16; 40] to achieve similar results to let robots recover their operational state after falling [41]. These robots were mainly tested under ideal conditions or used in the domain of duct inspection rather than a full false ceiling plenum. These robots were not designed to adapt to dark and disordered conditions for inspecting false ceiling interiors. The navigation requirements within disorderly structural arrangements and MEP components were not thoroughly explored in the case studies. A common type of inspection robot possesses wheel or tracked mechanisms. These mechanisms allow for easy deployment and adaptation in diverse settings, as well as having fewer components compared to legged or crawling modes of locomotion. As such, to maximise the efficacy of false ceiling robots in their inspection tasks, they should operate with minimal assistance from human operators until retrieval. This would involve determining the form factors and mechanisms to enable the robot to extract itself from scenarios whereby it gets stuck in a complex false ceiling environment by self-righting after being toppled over. The previous versions of Falcon robots were small inspection robots that utilised tracks for locomotion [42; 43; 44]. They were designed for false ceiling inspections within buildings that comply with the AS/NZS 2785 and BS EN 13964 false ceiling design standards [45]. They are installed with cameras for vision, enabling human workers to control the robot and view the plenum remotely for false ceiling inspection. The previous tracked version of the Falcon robot had issues with getting stuck due to protrusions in the false ceiling that trapped the robot in the middle, with the tracks being unable to pivot the robot away from the obstacle, or getting trapped due to the layout and positioning of the robot, as seen in Figure 1. This study thus sought to mitigate cases where such false ceiling inspection robots would become stuck in disordered false ceiling infrastructure by adding recovery mechanisms and determining the motions required for recovery. More research is needed to develop a refined mobile robot that is lightweight and that has visual capabilities to scope out false ceiling interiors and the ability to self-right.