Jebelli, Ali2014-07-102014-07-1020142014http://hdl.handle.net/10393/31283http://dx.doi.org/10.20381/ruor-3817Nowadays, small autonomous underwater robots are strongly preferred for remote exploration of unknown and unstructured environments. Such robots allow the exploration and monitoring of underwater environments where a long term underwater presence is required to cover a large area. Furthermore, reducing the robot size, embedding electrical board inside and reducing cost are some of the challenges designers of autonomous underwater robots are facing. As a key device for reliable operation-decision process of autonomous underwater robots, a relatively fast and cost effective controller based on Fuzzy logic and proportional-integral-derivative method is proposed in this thesis. It efficiently models nonlinear system behaviors largely present in robot operation and for which mathematical models are difficult to obtain. To evaluate its response, the fault finding test approach was applied and the response of each task of the robot depicted under different operating conditions. The robot performance while combining all control programs and including sensors was also investigated while the number of program codes and inputs were increased.enAUVAutonomous Underwater VehiclesADCAnalog to Digital ConverterCdDrag coefficient of the objectDOFDegree of FreedomKTThrust coefficientFdForce of draggAcceleration of gravityhHeight of the fluid above the objectKQTorque coefficientmbBuoyant massNNNeural networkPProportional controllerPIProportional-integral controllerPIDProportional-integral-derivative controllerρDensity of the fluidQTorque of the propellerROVRemotely Operated VehiclesRPMSpeed of the motor or propellerSDOSerial data outputSMCSliding mode control Measured thrustT°TemperaturevSpeed of the object relative to the fluidAVAdvance speed of the propellerThesis