Maintenance, Repair and Overhaul (MRO) operations in large infrastructures must often be carried out at height, putting workers in danger. Height is usually coupled with harsh conditions, such as wetness, frost, wind, dirt, or the presence of toxic substances, increasing the risk for human operators. Mobile robots can offer substantial social and economic benefits and relieve humans from health-threatening operations. However, many industrial environments, such as tankers, hydroelectric penstocks, and pipelines, pose significant challenges for robotics. This chapter presents Grace, a legged climbing robot designed to perform MRO operations in harsh conditions on horizontal, vertical, or upside-down surfaces. Grace is equipped with bio-inspired three-fingered feet, which enable climbing by vacuum. The optimization of the foot control strategy is performed, on one side, by performing an experimental campaign with the real foot, and on the other side, by leveraging Isaac Sim to evaluate full-body motion implications.