Arm-type Wearable Computer Hardware And Design

Wearable computer is a mobile computing device characterized by micromation, wearability, human-computer close integration and conjunction, constancy and users' hands-free. Now remarkable achievements for wearable computer have been made by researchers at home and aboard, applications are already appearing in military, industry, aerospace and medical field. However, the study of wearable computer is also a focus, and the research for more application areas is still a present trend.The special characteristics make wearable computer enhance user's capability. In logistics area, working with wearable computer can effectively improve user's ability to collect, transmit, and process data, and assist user to work naturally and constantly, thereby productivity and safety will be improved. Existent wearable computers can not satisfy the requirements in logistics application very well. Thus, after studying the advantages of wearable computer and combining with fieldwork status and information processing mode in logistics warehouse, we innovate in developing a forearm wearable computer as an application platform, study and design its hardware architecture deeply, finally realize a prototype system.Based on special restrictions of forearm wearable computer on power dissipation, volume and weight, this paper adopts Intel XScale PXA270 as the core of the hardware system after demand analysis and design scheme selection. Intel PXA270 processor is a high-performance, low-power, and integrated system-on-chip microprocessor, and hardware platform's structure is established based on it. We then analyze and design the circuits of each functional module, including memory module, human-computer interaction module, network communication module, RFID, power source module and so on, and these circuits are the basic of PCB design on core module and expand module.Forearm wearable computer presents critical demands to mainboard design (that is high-speed PCB and high desity layout), and PCB design of the system is done in Allegro. Combining with signal integrality theories and high-speed PCB design principles, we pick up some key signals' topological structures, simulate and adjust them, then present some layout rules. In this paper we finally debug circuits alone and through integrating software and hardware, and test power dissipation of the prototype system. According to these debugs, it is proved that the circuits designing for forearm wearable computer is correct and the hardware system basically satisfies the demands proposing before.This thesis can lay a basis for the research and design on a miniature and low power forearm wearable computer. It also can offer the references for design idea and implementation scheme when studying and designing wearable computer in other application areas.