Harness routing is one of the most time-consuming and error-prone processes among the design phases of a spacecraft project. In fact, the designer should take into account numerous constraints of electromagnetic and spatial nature, such as interferences between digital and analog signals or modules and elements that may constitute obstacles to unravelling of cables. The objective of this work is to create a software tool that, starting from a CAD model, allows the automation of the cabling routing process. Automation makes the process more responsive to changes and gives the designer a clearer idea of the final result. The routing problem was approached as an optimisation problem and implemented accordingly in the software.