The Ampelmann A-type hexapod platform is a motion compensating gangway system designed to transfer offshore personnel between a crew transfer ship and an offshore bottom founded structure. During operation, the platform is moved to compensate wave induced ship motion and create a still standing platform from which crew can safely transfer to the fixed structure. The hexapod platform is actuated by six high power linear actuators each capable of delivering 150 kW of power. To reduce the platform mass and reduce the operational energy requirements of the A-type, new actuator technologies are considered to replace the current conventional hydraulic actuators. Especially electro-hydrostatic and electro-mechanical actuation are promising alternatives to reduce mass and increase efficiency. Currently, properties of these technologies are only described up to power levels of 45 kW. Relative advantages of one over the other technology are not readily available in literature for higher power requirements.
To be able to compare both actuator technologies for use in the Ampelmann A-type, a preliminary design tool is made using existing and newly developed actuator mass and power loss models. General mass and loss properties of both actuators are determined and compared to develop a better insight in the optimal high power linear actuator technology for a specific application. Insights are applied but not limited to the Ampelmann application.