Three-dimensional analysis of relationship between relative orientation and motion modes

Abstract

Target motion modes have a close relationship with the relative orientation of missile-totarget in three-dimensional highly maneuvering target interception. From the perspective of relationship between the sensor coordinate system and the target body coordinate system, a basic model of sensor is stated and the definition of relative angular velocity between the two coordinate systems is introduced firstly. Then, the three-dimensional analytic expressions of relative angular velocity for different motion modes are derived and simplified by analyzing the influences of target centroid motion, rotation around centroid and relative motion. Finally, the relationships of the relative angular velocity directions and values with motion modes are discussed. Simulation results validate the rationality of the theoretical analysis. It is demonstrated that there are significant differences of the relative orientation in different motion modes which include luxuriant information about motion modes. The conclusions are significant for the research of motion mode identification, maneuver detection, maneuvering target tracking and interception using target signatures.

Target maneuver discrimination using ISAR image in interception

“…From the point of an implementation view, only sgn : s ½ and sgn[s] are selected in our paper as the indications of MDS. Although (11) should be satisfied in type P maneuver, it holds in most cases during [t sw ,t dir ]. This situation will be testified in Section 4 where the effect of ψ on discrimination performance is also explained more thoroughly.…”

“…The relationship between motion parameters and relative orientation of missile-to-target in a three-dimensional interception scenario has been derived in [11]. A twodimensional simplified analysis is presented to establish the ISAR imaging model as follows.…”

“…In (2), : γ : T and : q : represent the pose angle variety introduced by the target motion and relative motion of missile-to-target, respectively. It has been demonstrated in [11] that : q j j≪ : γ :…”

“…As stated in [11], the relative orientation of missile-to-target in interception can be approximated by a turntable model, which makes the maneuver discrimination using ISAR images possible. In fact, the estimation of motion parameters per se including translational motion velocity, rotation velocity, and direction is key to autofocus and cross-range scaling in ISAR imaging, and many signal-domain and image-domain methods have been proposed [12][13][14][15].…”

Design of Die-Casting Die with Double-Stage Linkage Hydraulic Core-Pulling Mechanism

“…The once-stage hydraulic core-pulling mechanism is easily to cause the above thin parts deformation, crack, abruption and make the blank scrapped. So the once-stage hydraulic core-pulling mechanism is not appropriate and the double-stage hydraulic core-pulling mechanism is reasonable and be determined [4,5,6,7,8,9]. The double-stage hydraulic core-pulling mechanism was designed as shown in Fig.…”