electro permanent - servo

During this semester I used Servo motors as actuators to for the sailing drone. These servo motors require constant power when a force is applied on the rudder or sail. In other words they just require constant power because the wind always applies a force on the sail as well as the water applies a force on the rudder. Therefore I started looking for other ways to steer and adjust the sail. Unfortunately there are not really power efficient actuators on the market.

But recently I saw an article about "kleefklimmen" (http://www.schuttevaer.nl/nieuws/actueel/nid12488-europort-kleefklimmen-op-europort-2009.html) a technique which uses electropermanent magnets to climb on any steel structure (or any magnetisable material) The main advantages of this system are no power consumption while the magnet is on, which is much saver in the application of climbing. But this technique of electro permanent magnets can also be used to lock the sail actuator and rudder in position which cause them to use absolutely no power while they are locked in this position. Because the sailing drone will sail large distances in the same direction the and sail settings don't need to be adjusted continuously which can save a lot of energy.

The sailing drones will be autonomous and thus harvest their own energy with solar cells or in any other way. But the fact is there is a limited amount of energy available for the sailing vessel at open sea. Therefore this system can save a lot of energy, compared with normal servo's which require constant power.

For now I will make an appointment with Henk Huisman an expert on electro permanent magnets which I came in contact with through Bas Gravendeel the inventor of "kleefklimmen". in the next post I hope to give more information about the strength and power consumption of the system as a total.


For those with a bit of physics background, these B-H curves tell the story