## 1 Introduction  
Although the accuracy of the existing numerical codes in aerospace structure simulation is increasing steadily, Aircraft Strength Testing (AST) is still considered the preferred means for reliable simulation. Airframe and component strength testing is used to measure and analyze structure parameters and performance (e.g., stress, displacement, vibration amplitude, and fatigue life) for the evaluation and validation of structure mechanical properties and theory design. Fatigue and static tests in ground testing facilities are one of the most important means of research of aircraft structure strength. Traditionally, the cable-based AST systems for aircraft structures usually involve large numbers of wires employed for communication among sensors and centralized data acquisition systems. These wires on specimen structures can be cumbersome, which brings high installation costs and inefficient maintenance. As sensors have no means to locally process their data, the centralized data server is responsible for the aggregation, storage and processing of all measurement data. If AST systems include hundreds, or even thousands, of testing sensors, the testing task computations in a centralized testing system can become burdensome and time-consuming.  
In response to the cost and performance shortcomings of centralized cable-based AST systems, this paper present an exploration of wireless sensor network (WSN) technology for adoption in AST systems. In recent years, WSN has been applied in many engineering fields, ranging from national defense and military affairs, to behavior observation of animals, structural health monitoring, traffic controls, medical treatment and sanitation and disaster monitoring. [PERSON] _et al_. [PERSON] _et al_. (2008) proposed a decentralized method of shooter localization and weapon classification using soldier-wearable networked sensors. [PERSON] and [PERSON] [PERSON] and [PERSON] (2008) were the first to describe algorithms for structural health monitoring using wireless sensors. [PERSON] _et al_. [PERSON] _et al_. (2008) designed a low-cost wireless sensing unit for deployment as the wireless structural monitoring system on the Alamosa Canyon Bridge. [PERSON] _et al_. [PERSON] _et al_. (2009) described the design and evaluation of a wireless sensor network system called Wisden for structural data acquisition based on the Mica-2 motes. [PERSON] _et al_. [PERSON] _et al_. (2009) and [PERSON] _et al_. [PERSON] _et al_. (2010) developed a composite structural health monitoring system base on the Mica wireless platform and multi-agent technology. However, there has been no similar research related to WSNs designed for AST applications.  
The research in this paper aims to develop a WSN based aircraft AST system design. A small-size, high-precision, and shock-proof wireless sensor node is designed for multi-channel strain gauge signal conditioning and monitoring. To address the need for low-power consumption, timeliness, and scalable operations, a cluster-star network topology protocol is adopted and researched. The application layer interface is designed in detail. To verify the functionality of the designed wireless sensor network for distribution AST capability, a multi-point distribution testing system is developed for static tests of a real aircraft undercarriage. The experimental results prove the advantages of the wireless sensor network based AST system, compared to the conventional cable-based AST system.