A multiscale transform denoising method of the bionic polarized light compass for improving the unmanned aerial vehicle navigation accuracy

In recent years, the bionic polarized light compass has been widely studied for the unmanned aerial vehicle navigation. However, it is found from the obtained investigation results that a polarized light compass with a sensitive and high dynamic range polarimeter still provides inferior output precision of the heading angle due to the presence of the noise generating from the compass.The noise is existed not only in the angle of the polarization image acquired by polarimeters but also in the out...     

Unintentional modulation evaluation in time domain and frequency domain

With the development of wireless communication technology, the electromagnetic environment has become more and more complex. Conventional signal identification methods are difficult to accurately identify illegal devices. However, electromagnetic signals have an unavoidable device-specific characteristic unintentionally generated by a transmitter, appearing in the form of an Un Intentional Modulation(UIM), namely Radio Frequency Fingerprint(RFF). RFFs can be used to uniquely identify an emitter ...     

Conceptual design and analysis of legged landers with orientation capability

The lander with orientation capability is of fundamental importance for the “Returning” mission because its body can be the base with a suitable launching angle for the ascender lifting off. This paper proposes the conceptual design and verification of Landers with Orientation Capability (LOCs). Firstly, the topological composition of the lander is analyzed and expressed in the form of Lie group, which provides the fundamental principle for the type synthesis of LOCs. Then, the type synthesis approach for designing LOCs is proposed, which includes designing the Equivalent Parallel Mechanism (EPM) and the auxiliary limbs. Numerous mechanisms of LOCs with two-dimensional rotational motions are obtained based on the type synthesis approach by developing and combining the EPMs and auxiliary limbs. Afterward, kinematics and Jacobian matrix of a typical legged lander are developed, the workspace is analyzed, singularity configurations are analyzed based on the wrench graph method, and finally, the orientation capability is analyzed. The pitch and yaw angle reach 17.5°, considering the permissible range of joints. The proposed types of LOCs offer potential candidate for the “Returning” mission of the exploration mission.