Abstract: Systems and methods for visual inspection of a container such as an oil tank via a lighter-than-air aircraft are presented. According to one aspect, the aircraft includes a gondola attached to a balloon filled with lighter-than-air gas. Rigidly attached to the gondola is a suite of sensors, including a camera sensor, an inertial measurement unit and a range sensor. Navigation of the aircraft is based on information sensed by the suite of sensors and processed by control electronics arranged in the gondola. Embedded in the control electronics is an extended Kalman filter that calculates pose estimates of the aircraft based on the information sensed by the inertial measurement unit and updated by the camera sensor. The extended Kalman filter uses the information sensed by the range sensor to reduce uncertainty in the calculated pose estimate. Images captured by the camera sensor can be used to evaluate state of the container.

Abstract: A compact, high torque actuator includes a brushless motor, motor control electronics, an inner hollow tube to transmit rotation of an output plate to the input end of the actuator, thus allowing two absolute magnetic encoders to read an absolute position of the input and output of the actuator. The actuator is sealed to operate in fluid environment at high pressures.

Abstract: A compact, high torque actuator includes a brushless motor, motor control electronics, an inner hollow tube to transmit rotation of an output plate to the input end of the actuator, thus allowing two absolute magnetic encoders to read an absolute position of the input and output of the actuator. The actuator is sealed to operate in fluid environment at high pressures.

Abstract: Designing intrinsically safe robotic inspection systems used for unmanned navigation and inspection of large tanks with hazardous and explosive atmosphere is challenging. The disclosed methods and devices provide solutions to overcome such challenge. Intrinsically safe devices and methods using a combination of a lighter-than-air blimp with various intrinsically safe subsystems attached to the blimp are presented.