Robotic inspection is the use of drones, fixed cameras and underwater robots to inspect turbine blades, dams, ship hulls and plants for cracks, corrosion and safety risks. Corrosion is the slow eating away of metal. The robot goes where it is dangerous or costly for a person to go.
Take, for example, a wind farm near Chitradurga in Karnataka. Each blade of its older turbines is about 40 metres long, on a tower about 90 metres tall. Newer turbines in India have blades of about 70 metres. Inspecting a blade by climbing it with ropes takes hours, and the turbine must stop. A drone can fly along all three blades in less than half an hour and take hundreds of close photographs. Software then reads the photographs, marks each crack or damaged spot, and gives each a severity grade. The owner decides which blades need repair.
The same idea is used elsewhere. An underwater robot looks at a dam wall without emptying the reservoir. A camera fixed on a plant reads corrosion and safety risks all day, using video analytics. Some sites keep a drone in a box, a drone in a box, which launches itself on a schedule. Cameras that see heat, called thermal imaging cameras, show overheating parts. Inspecting a wind turbine is the most common use.
Robotic inspection saves money and risk in three ways. A person does not have to climb or enter a tank. The machine does not need to stop for as long. And the photographs are kept, so next year's inspection can be compared with this year's, which shows how fast a crack is growing. In India, drone flights are regulated by the Directorate General of Civil Aviation (DGCA), and operators need permission for flights near sensitive sites.
The findings feed the rest of predictive maintenance. They are added to the plant digital twin, and they are used by asset performance management (APM) software to decide which machines need attention next.