Projectile Fin Deployment Mechanism with Counterweight Balance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current fin deployment mechanisms for rotationally stabilized projectiles consume high energy due to the need to overcome centrifugally created forces during deployment and retraction, requiring powerful motors and bulky energy sources, which are unsuitable for integration on projectiles.
Innovation Solution
A fin deployment mechanism using balance weights that displace radially in opposite directions to the fins, compensating radial deployment forces, allowing for energy-efficient deployment and retraction by balancing centrifugal forces with equally large and equidirectional radial forces on the balance weights.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If fins are frequently deployed and retracted during projectile travel, then guidance precision is improved, but energy consumption increases significantly
Solution Approach 1:
The patent applies counterweights that move in opposite direction to the fins during deployment and retraction. When fins are deployed outward, counterweights move inward, and vice versa. This creates balancing forces that compensate for the centrifugal forces acting on the fins, significantly reducing the energy required for fin actuation while maintaining frequent deployment capability for precise guidance
2Reliability
If powerful motors are used to retract fins against centrifugal forces, then fin retraction reliability is improved, but device size and complexity increase
Solution Approach 1:
Counterweights are employed to balance the centrifugal forces acting on the fins during retraction. By moving in the opposite direction to the fins, the counterweights create compensating forces that reduce the load on the actuator, allowing reliable fin retraction with a smaller, less complex motor system
Solution Approach 2:
The patent introduces asymmetry in the mass distribution through counterweights positioned opposite to the fins. This asymmetric configuration creates the necessary balancing effect during rotation, enabling the actuator to overcome centrifugal forces more efficiently without requiring excessive power
3Use of energy by moving object
If bulky energy sources are integrated on projectiles to power fin deployment, then deployment capability is improved, but projectile design flexibility deteriorates
Solution Approach 1:
The counterweight mechanism dramatically reduces the energy required for fin deployment and retraction. This energy reduction allows the use of compact power sources that can be integrated into the projectile without compromising its aerodynamic design or requiring bulky battery systems, thereby maintaining design flexibility
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Significantly reduces energy consumption for fin deployment and retraction, enabling the use of smaller motors and potentially eliminating the need for bulky energy sources, thereby improving the energy efficiency of the mechanism.
Implementation Method 1
the radial deployment force acting on the fin is compensated with an equally large and equidirectional radial force acting on the balance weight
Data Source
Figure 1
Figure 2~3
Figure 4a
AI summary
The invention relates to a fin deployment mechanism (10, 20) for a rotationally stabilized projectile (1), comprising at least one fin (2, 15) and at least one actuator, in which the fin (2, 15) is arranged in a deployable and retractable manner on the projectile (1), and in that the fin (2, 15) and at least one balance weight (3, 17) are mechanically arranged so that, when the fin (2, 15) is deployed by the actuator, then the balance weight (3, 17) is displaced in towards the centre (6) of the projectile (1) and, when the fin (2, 15) is retracted by the actuator, then the balance weight (3, 17) is displaced out from the centre (6) of the projectile (1). The invention also relates to a method for energy-efficient deployment and retraction of fins (2, 15) on a rotating projectile, in which at least one fin (2, 15) is arranged in a deployable and retractable manner on the projectile, and in which the fin (2, 15) is fitted to at least one balance weight (3, 17) according to: (a) when the fin (2, 15) is displaced out from the centre of the projectile, upon deployment of the fin (2, 15), the balance weight (3, 17) is displaced in towards the centre of the projectile, (b) when the fin (2, 15) is displaced in towards the centre of the projectile, upon retraction of the fin, the balance weight (3, 17) is displaced out from the centre of the projectile.