Quantifying the Impact of the Physical Setup of Stereo Camera Systems on Distance Estimations

The ability to perceive the environment accurately is a core requirement for autonomous navigation. In the past, researchers and practitioners have explored a broad spectrum of sensors that can be used to detect obstacles or to recognize navigation targets. Due to their low hardware cost and high fidelity, stereo camera systems are often considered to be a particularly versatile sensing technology. Consequently, there has been a lot of work on integrating them into mobile robots. However, the existing literature focuses on presenting the concepts and algorithms used to implement the desired robot functions on top of a given camera setup. As a result, the rationale and impact of choosing this camera setup are usually neither discussed nor described. Thus, when designing the stereo camera system for a mobile robot, there is not much general guidance beyond isolated setups that worked for a specific robot. To close the gap, this paper studies the impact of the physical setup of a stereo camera system in indoor environments. To do this, we present the results of an experimental analysis in which we use a given software setup to estimate the distance to an object while systematically changing the camera setup. Thereby, we vary the three main parameters of the physical camera setup, namely the angle and distance between the cameras as well as the field of view. Based on the results, we derive several guidelines on how to choose the parameters for an application.