Design, Testing, and Simulation of a Low-Cost, Light-Weight, Low-g IMU for the Navigation of an Indoor Blimp

Abstract

In this thesis we develop an IMU for the purpose of navigating an autonomous indoor blimp. Due to the unique system properties of an indoor blimp, the developed IMU is light-weight and is capable of measuring slow rotational rates and accelerations. An emphasis is placed on maintaining low cost by using commercially available off-the-shelf components.

We present an overview of current IMU technology and evaluate that technology's suitability for use with an indoor blimp. Through this evaluation we conclude that commercially available IMUs are not viable so an IMU must be designed. We present design constraints that must be met and evaluate commercially available sensors that can meet these constraints. After selecting the most appropriate hardware, we integrate the sensors to form an IMU.

The constructed IMU is tested, modeled, and simulated. We test the IMU by applying known constant inputs and evaluating the sensors' outputs. Models of the sensors are developed from the test data. The models are then evaluated based on autocorrelation methods. Based on experimental observations, we also develop a mathematical model of an indoor blimp in closed loop with guidance and control laws. We perform several simulations to evaluate the IMU's ability to accurately measure the blimp's states.