Development of a Semi-autonomous Holonomic Load Carrier with Multi-camera Perception

Master's thesis in Mechatronics (MAS500)This thesis documents the development of a load carrier capable of carrying ten advanced personal robots. The robots of concern are Segway Robotics’ Loomo,which are used for education purposes at the University of Agder. They are used at multiple locations on campus, and it is desired to develop a system that can effectively transport them around. The report covers the concept generation, mechanical design, electrical design and development of a navigation system. A simple and compact design was developed and built. To achieve holonomic drive, the rig was equipped with four mecanum wheels. A mechanical design process was performed tocome up with a solution for mounting the wheels to the rig. This included design of an axle and bearing calculations. Additionally, the stability of the rig had to be verified. Further on,to drive the mecanum wheels, four brushless dc motors were utilized. The system consist of multiple hardware components, which needed to communicate with each other. The solution for this is documented in this report

Modeling and identification of the Quanser Aero using a detailed description of friction and centripetal forces

This paper deals with the modeling and identification of the Quanser Aero. The Quanser Aero is an aerospace laboratory setup designed for teaching aerospace concepts. Two propellers generate thrust and allow the user to control its dynamic response. The ability to lock axes individually makes it capable of abstracting a variety of aerospace systems, such as half-quadrotor, 1-Degree of freedom (DOF), vertical take-off and landing (VTOL), and 2-DOF helicopter. This paper focuses on the latter of these modes. In this configuration, the Quanser Aero can produce different pitch and yaw angles based on the angular velocity of the propellers, which produces an interesting identification and control problem, due to the presence of nonlinearities and significant cross-couplings between different variables. In this paper, a nonlinear model derived from Newton’s law and Euler’s rotational dynamics is obtained, and the unknown model parameters are identified through an experimental approach, with the model validated through real-time testing. In particular, it is shown that by means of a more detailed description of the friction, which includes the Karnopp’s model that keeps the sum of the magnitude of all forces equal to zero until the applied forces are strong enough to overcome the friction force, and of the centripetal forces acting on the Aero, significant improvements are obtained when compared to state-of-the-art models. These improvements may hold the potential to enhance the performance of advanced nonlinear model-based control algorithms for this device.publishedVersio

The Control Zendo: A Game of Inductive Logic for Teaching Automatic Control

Board games and card games have been used with some degree of success in the implementation of active strategies for education, since they stimulate problem solving and increase the learning and engagement of the students. This paper shows how the mechanics of the popular game Zendo have been adapted to teach elements of a basic automatic control course at the University of Stavanger. The result is the Control Zendo, a game of inductive logic in which a hidden rule related to different system's properties (e.g., linearity, time-varyingness or number of input and output variables) must be guessed. Implementational issues and the feedback received by the students who played the game in Spring 2022 are discussed.publishedVersio

Development of a Semi-autonomous Holonomic Load Carrier with Multi-camera Perception

This thesis documents the development of a load carrier capable of carrying ten advanced personal robots. The robots of concern are Segway Robotics’ Loomo,which are used for education purposes at the University of Agder. They are used at multiple locations on campus, and it is desired to develop a system that can effectively transport them around. The report covers the concept generation, mechanical design, electrical design and development of a navigation system. A simple and compact design was developed and built. To achieve holonomic drive, the rig was equipped with four mecanum wheels. A mechanical design process was performed tocome up with a solution for mounting the wheels to the rig. This included design of an axle and bearing calculations. Additionally, the stability of the rig had to be verified. Further on,to drive the mecanum wheels, four brushless dc motors were utilized. The system consist of multiple hardware components, which needed to communicate with each other. The solution for this is documented in this report