Detaljkonstruktion av låsmekanism

Abstract

The non-profit organization Swedish Sea Rescue Society (SSRS) works with rescue missions at the sea. The organization is currently developing a drone launcher. At this current time, the development is in a prototype phase. In the future, the goal is to be able to place drone launchers along the coasts of Sweden. The drone launcher consists of a drone housing on which a drone is mounted and a column on which the drone housing is mounted. When an accident occurs at sea, a drone will be fired from the drone launcher and fly to the area where the accident occurs. Sea rescuers will receive live footage from the drone and will be able to be more prepared when they arrive at the accident. The column on which the drone housing is mounted can rotate about its own axis using an electric motor. In addition to rotate and fire the drone against the direction of the wind, it rotates automatically to protect the drone from direct sunlight and to counteract the stresses of the wind on the drone launcher. However, once the electric motor has rotated the drone launcher to a new position, there is nothing holding the stand in place. Because of this, the drone launcher can rotate freely, which means that the electric motor must ensure the position of the drone launcher. Eventually, the drone launcher’s battery will drain. To solve this problem, a locking mechanism was developed which ensures that the drone launcher is locked in its position when it is not supposed to rotate. The project was done by a collaboration between SSRS and the consultant company Infotiv, where Infotiv provided technical support and project management. The project was limited to the area at the bottom of the drone stand. One of the things in this area is a gear, which an electric motor uses to rotate the drone launcher. The locking mechanism locks the drone launcher by inserting a wedge between two teeth on this gear. The axial movement which inserts the wedge is performed by a so-called bistable solenoid, which is a component that can perform linear axial movement by moving a shaft. The shaft can be either in an extended or retracted position. In the extended position, the drone launcher is locked and in the retracted position it is unlocked. The solenoid only needs power to change the position of the shaft. An enclosure was made of an ABS-like material to protect the solenoid against water. The enclosure is designed to withstand the forces of which the locking mechanism is exposed to. It is attached to a plate above the gear which the locking mechanism is applied to. The result of the work is a working product which can be used on the Sea Rescue Society’s drone launcher prototype.