The Inertial Navigation Unit: Teaching Navigation Principles Using A Custom Designed Sensor Package

This paper describes the application and design of a small, inexpensive inertial navigation unit (INU) created to introduce systems engineering students at the United States Naval Academy (USNA) to the principles of navigation systems and to act as a navigation sensor for robotic and autonomous vehicle projects. The INU has been used in place of a multitude of standard navigation sensors such as an inertial measurement unit (IMU), magnetic compass module, and Global Positioning System (GPS) receiver. Its integrated design simplifies mechanical mounting, reduces navigation system weight and size, simplifies data interfacing with a control computer, and provides great flexibility for reconfiguring to meet a variety of engineering education objectives. The INU is capable of firmware upgrades and algorithm enhancements in the field via in-circuit programming, enhancing its longevity as a useful educational tool. In addition, a variety of controllers or a personal computer (PC) can communicate with the INU board through a standard RS-232C serial interface. This compact unit provides good system performance at a reasonable cost compared to most commercially available units. These features enable hands-on education techniques in the navigation aspects of robotics, examples of which are presented.