Missile

About: Missile is a research topic. Over the lifetime, 12829 publications have been published within this topic receiving 94307 citations. The topic is also known as: guided missile & missiles.

Modern Control Theory for Design of Autopilots for Bank-to-Turn Missiles

Abstract: The state-space techniques of modern control theory are used to develop a methodology for the design of autopilots for bank-to-turn missiles. The methodology accommodates the gyroscopic and coriolis cross-coupling between the pitch and the yaw axes that result due to the high roll rates that can be present. The design uses the assumption that the roll rate is constant, but not zero, and results in an autopilot structure in which there are cross-couplings between the pitch and yaw channels that are dependent on the roll rate. The autopilot gains are also scheduled as functions of the dynamic pressure. A reduced-order extended Kalman filter, with fixed gains, is used to estimate the actuator states and the commanded acceleration. The performance of an autopilot designed by this methodology was evaluated in a six-degree of freedom simulation using the dynamics of a typical high-performance tactical missile. Excellent performance was obtained in teres of low miss distance and small side-slip.

Comparison of different Constitutive Models for Concrete in ABAQUS/Explicit for Missile Impact Analyses

Abstract: This EUR report describes numerical missile impact analyses on a reinforced concrete slab performed at JRC-IE using the Finite Element (FE) solver ABAQUS/Explicit. The FE model of the impacted reinforced concrete slab resembles a structure used in the missile impact tests by Hanchak et al. FE analyses with a hard (rigid) and a soft (deformable) missile are performed. Traditional Lagrangian formulation for both the missiles and reinforced concrete slabs are used. Two different build-in constitutive models for concrete in ABAQUS/Explicit, the Brittle Cracking Model and the Concrete Damaged Plasticity Model, are compared with each other and their suitability and limitations for missile impact analyses are explored. It turns out that only the Concrete Damaged Plasticity Model in combination with a soft missile leads to physically reasonable and sound results in terms of strains/stresses of the reinforced concrete slab, overall energy balances and overall deformation of the concrete slab when a traditional Lagrangian formulation is used for both missile and reinforced concrete slab. How to obtain EU publications Our priced publications are available from EU Bookshop (http://bookshop.europa.eu), where you can place an order with the sales agent of your choice. The Publications Office has a worldwide network of sales agents. You can obtain their contact details by sending a fax to (352) 29 29-42758. The mission of the JRC is to provide customer-driven scientific and technical support for the conception, development, implementation and monitoring of EU policies. As a service of the European Commission, the JRC functions as a reference centre of science and technology for the Union. Close to the policy-making process, it serves the common interest of the Member States, while being independent of special interests, whether private or national. LD -N A -2451-EN -C

Dual-control scheme for improved missile maneuverability

Abstract: A cooperative dual-control strategy actuates forward and aft control devices simultaneously to significantly improve a missile's maneuverability/dynamic capability. A substantial, and measurable, operational effect of the inventive control strategy is a dramatic improvement in a missile's divert capability. To effect a maneuver in accordance with the inventive strategy, a missile's aft fins are initially deflected to generate a force OPPOSITE that conventionally used (pushing the missile's tail in the direction of the commanded maneuver) while simultaneously actuating forward thrusters to also push the missile's nose in the direction of the commanded maneuver but at a faster rate than the tail section. This causes the missile body to simultaneously rotate and translate in the direction of the commanded maneuver. Once a sufficient amount of aerodynamic force develops due to body rotation, the aft fins are deflected to generate a force that opposes the commanded maneuver to maintain a moment on the missile body and complete the commanded maneuver. An important benefit of cooperative dual-control strategy is that the missile begins to translate in the direction of the commanded maneuver immediately (conventional isolated aft control schemes do not accomplish this) and at a faster rate than is possible with either isolated forward control devices or an intuitive dual-control approach.