Designing a robot is rarely a straightforward adventure. You will have to cross domains and travers barriers between disciplines; mechanical, vision, AI, controls, data sciences and sociology, have to work together for a successful robot. The expertise needed to design these complicated systems are rarely unified in one person. This means teamwork, communication and formalizing a design approach. In this talk a systematic design approach is proposed and shown for various application fields. We will disassemble several robots to see of which elements it consists of. Then, we will try to put these elements back together and observe what could go possibly wrong. We will have a look at different upcoming application fields for robots (collaborative, medical and agro/food robots) and see which challenges are associated to these trends and how we could overcome them.