Quadrotors are Vertical Take-Off and Landing aerial vehicles with many potential applications ranging from mapping to supporting rescue operations. This paper aims to provide an overview on various works carried out on the quadrotor, from the perspective of control and dynamic modelling. Also in this paper, based on the information summarized from 160 researches available, different control targets and flight missions are analysed and classified, and according to it, a general flight mission map is introduced. In addition, history of advances in development of quadrotors and set-ups proposed when performing experimental researches on quadrotors is presented.

Tendon injuries are frequent, and surgical interventions toward their treatment might result in significant clinical complications. Pretendinous adhesion results in the disruption of the normal gliding mechanism of a damaged tendon, painful movements, and an increased chance of rerupture in the future. To alleviate postsurgical tendon-sheath adhesions, many investigations have been directed toward the development of repair approaches using electrospun nanofiber scaffolds. Such methods mainly take advantage of nanofibrous membranes (NFMs) as physical barriers to prevent or minimize adhesion of a repaired tendon to its surrounding sheath. In addition, these nanofibers can also locally deliver antiadhesion and anti-inflammatory agents to reduce the risk of tendon adhesion. This article reviews recent advances in the design, fabrication, and characterization of nanofibrous membranes developed to serve as (i) biomimetic tendon sheaths and (ii) physical barriers. Various features of the membranes are discussed to present insights for further development of repair methods suitable for clinical practice.

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Peritendinous adhesion is considered a major postsurgical tendon complication in hand surgery. This complication could be mitigated partially through early tendon mobilization. However, development of new treatment modalities to guide tissue regeneration and to reduce postsurgical tendon adhesion has recently gained attentions. In this article, synthesis and characterization of electrospun nanofibrous membranes (NFMs) of polycaprolactone (PCL) and chitosan to form a physical barrier against cellular migration leading to tendon adhesion is presented. The mechanical properties of the NFMs are modulated to maintain high integrity during postsurgical tendon mobilization. The tensile strength of the NFMs is examined in wet and dry conditions after 1000 cyclic pull loadings. In addition, the mechanical strength of the NFMs is evaluated after a degradation period of 30 days. To obtain NFM with desired properties, concentrations of polymer solutions, operation parameters of electrospinning and the thickness of NFMs were optimized. Based on the biodegradation and mechanical evaluations, the optimum NFM was obtained for specified amounts of PCL (5 wt %) + chitosan (2 wt %) at an electrospinning drum speed of 400 rpm. The engineered NFM could withstand forces of 33 and 19 N before and after 1000 pull cycles that are sufficient during tendon healing process. The bonding of chitosan fibers over PCL nanofibers allowed for production of NFMs with appropriate mechanical integrity and degradation rate. In vitro cell culture tests demonstrated that PCL/chitosan could only have minor impact on decreasing fibroblast attachment over the membranes probably due to protonation of amine groups.