Abstract: A system includes a navigation apparatus and controller. The navigation apparatus includes a body assembly that includes a plurality of pneumatic or artificial muscles that are configured to interact with a sidewall of the conduit and move the body assembly through the conduit. The plurality of pneumatic or artificial muscles are independently actuated to steer the body assembly. The navigation apparatus also includes a sensor array coupled to the body assembly. The sensor array is positioned to interact with the sidewall of the conduit and provide signals as the body assembly moves through the interior cavity. The controller is communicatively coupled to the sensor array and configured to determine a characteristic of the conduit based on the signals provided by the sensor array.