This project proposes a solution to the problem of maintaining the infrastructure of bridges and otherstructures. New designs and technologies allow bridges to be built higher, reach longer, and span ariver, valley or sea that were deemed impossible to cross before. This creates hazardous environmentsthat are hard for humans to reach, making the labour intensive inspection and maintenance processineffective. Such hazardous inspection and maintenance environments are not limited to bridges andexist across all forms of critical infrastructure. However, this task may have the potential to be done byautonomous systems. In this project we aim to create a coordinated aerial swarm system to inspect thecracks in the bridge structures, improving the monitoring coverage and efficiency. With strict constraintsof the environments and mutual interference, the development of such multi-UAV system for bridgeinspection is challenging. We have achieved the following objectives of the project: Agile coordinationand collision avoidance for aerial swarms (WP1); Image based bridge defect detection and assessment(WP2); System integration and validation (WP3)