This paper presents a sliding mode control method for wheeled mobile robots. Because of the nonlinear and nonholonomic properties, it is difficult to establish an appropriate model of the mobile robot system for trajectory tracking. A robust control law which is called sliding mode control is proposed for asymptotically stabilizing the mobile robot to a desired trajectory. The posture of the mobile robot (including the position and heading direction) is presented and the kinematics equations are established in the two-dimensional coordinates. According to the kinematics equations, the controller is designed to find an acceptable control law so that the tracking error will approximate 0 as the time approaches infinity with an initial error. The RFID sensor space is used to estimate the real posture of the mobile robot. Simulation and experiment demonstrate the efficacy of the proposed system for robust tracking of mobile robots.

The aprotic Li-CO 2 battery is emerging as a promising energy storage technology with the capability of CO 2 fixation and conversion. However, its practical applications are still impeded by the large overpotential. Herein, the general synthesis of a series of ultrathin 2D Ru-M (M = Co, Ni, and Cu) nanosheets by a facile one-pot solvothermal method is reported. As a proofof-concept application, the representative RuCo nanosheets are used as the cathode catalysts for Li-CO 2 batteries, which demonstrate a low charge voltage of 3.74 V, a small overpotential of 0.94 V, and hence a high energy efficiency of 75%. Ex/in situ studies and density functional theory calculations reveal that the excellent catalytic performance of RuCo nanosheets originates from the enhanced adsorption toward Li and CO 2 during discharge as well as the elevated electron interaction with Li 2 CO 3 during charge by the in-plane RuCo alloy structure. This work indicates the feasibility of boosting the electrochemical performance of Li-CO 2 batteries by in-plane metal alloy sites of ultrathin 2D alloy nanomaterials.

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Neurorestoratology is a newborn and emerging distinct discipline in the neuroscience family. Its establishment will definitely speed up the advance of this promising frontier realm. A worldwide association for Neurorestoratology and several official journals covering this discipline have recently been set up. Clinical practice has demonstrated that the sequelae of damages and diseases of the CNS can be functionally restored to some degree. Obstacles that hinder the promising methods of Neurorestoratology to be translated from the bench to the bedside include political, governmental, religious, ethical, economic, and scientific factors or in most instances they work in combination. Falsehoods against the recognition of neurorestoratology include: 1) no therapeutic method is currently available that suggests that it is possible to repair, even partially, neurological functions; 2) according to the media, a cure will be very soon found for patients with severe spinal cord injury, brain trauma, and progressively deteriorated CNS degenerative diseases; 3) randomizing double blind control designed studies are the only gold standard for clinical study; self-comparison designed studies should be ignored and neglected. Future directions for neurorestoratology include the comparison and integration of current and upcoming available neurorestoration methods to look for the optimization regimes, and edit and publish clinical neurorestoratology treatment guidelines.

Flexible fiber‐shaped Li‐CO2 batteries are regarded to be a potential candidate to power accessories for wearable electronics due to their high theoretical energy density and carbon‐neutral capability. However, the difficulties of electrode preparation and architecture design make it challenging for current Li‐CO2 batteries to keep a suitable balance between electrochemical performance and multifunctionality, one‐dimensional configuration and so forth. Herein, a flexible, stretchable, water‐/fire‐proof fiber‐shaped Li‐CO2 battery is constructed through an integrated electrode design strategy and a mechanical engineering‐inspired “spring”‐like device architecture. Impressively, the as‐prepared highly‐active Mo2N anchored N‐doped carbon nanotubes/carbon fiber hybrid bundle (CFB@NCNT‐Mo2N) cathode delivers a large full capacity of 5586.0 µAh cm−1, corresponding to a high energy density of 14 250 Wh kgcathode−1\[{\rm{Wh}}\,{\rm{kg}}_{{\rm{cathode}}}^{{\bm{ - }}1}\]. Meanwhile, it also demonstrates a low charge potential of ≈3.7 V, excellent rate capabilities, and outstanding long‐term cycling stability of 525 cycles. Furthermore, the constructed “spring”‐like fiber‐shaped Li‐CO2 battery device using CFB@NCNT‐Mo2N and a newly‐proposed gracile fibrous Li metal anode exhibits excellent adaptability to deformations including bending and stretching, as well as other favorable features like water‐/fire‐resistance. The successful demonstration of the proposed high‐performance and multifunctional Li‐CO2 batteries provide an effective model for designing future flexible energy storage devices beyond metal‐gas batteries for wearables in specific application scenarios.

The high density of small aircrafts increasingly threatens flight safety during lowaltitude flights. Unlike general air transport aircraft, small aircrafts do not install active detection for collision avoidance. Through available surveillance communication, small aircraft can be monitored and separated on a surveillance dependence basis. A low-altitude collision avoidance system algorithm is introduced to offer the required separation solution to small aircrafts at low altitude. Based on the automatic dependent surveillance concept under the visual flight rule, aircraft traffic alert and collision avoidance system operation can be built on a ground surveillance computer as well as being installed as a airborne electronic flight instrument system (EFIS). Aircraft conflict will be detected and calculated from the surveillance information. Simple traffic resolution rules can be created for collision avoidance after alerts are simultaneously generated on the ground computer and on airborne EFIS. Following the general basic rules, the resolution algorithm could be induced. This article refers to traffic advisory and resolution advisory, and designs a simple avoidance manipulation for small aircrafts. In this development, ultra-light flights are operated to create the actual flight data in a small airspace. Several feasible scenarios are tested in simulations to look into the TCAS performance on ground computer and airborne EFIS. The results offer better flight safety management for low-altitude flights.

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