The HEMS crew is planning to conduct research on implementing ECPR treatment during OHCA cases. A data collector that collects time and chest compression data is needed for the research. Thus, this graduation project is focused on the design of a data collector for HEMS crew during OHCA. This report describes the whole process of developing the design of the data collector. The process starts with a design brief that elaborates the design assignment. Then four cycles of project development are carried out: the first cycle is focused on context analysis and exploration of possible solutions; the second cycle is focused on the electronics prototype and data transfer system building; the third cycle is focused on the housing design of the collector; the last cycle is concluded with a validated final design and recommendations on implementation. This project collaborates with Dr. Dinis Reis Miranda from the HEMS lifeliner 2 and Erasmus MC - University Medical Center.