Dynamic leveling control of a wireless self-balancing ROV using fuzzy logic controller

A remotely operated vehicle (ROV) is essentially an underwater mobile robot that is controlled and powered by an operator outside of the robot working environment. Like any other marine vehicle, ROV has to be designed to float in the water where its mass is supported by the buoyancy forces due to the displacement of water by its hull. Vertically positioning a mini ROV in centimetres resolution underwater and maintaining that state requires a distinctive technique partly because of the pressure and buoyancy exerted by the water towards the hull and partly because of the random waves produced by the water itself. That being said, the aim of the project is to design and develop a wireless self-balancing buoyancy system of a mini ROV using fuzzy logic controller. A liquid level sensor has been implemented to provide feedback to the Arduino microcontroller. A user-friendly graphical user interface (GUI) has been developed for real-time data monitoring as well as controlling the vertical position of the ROV. At the end of the project, the implemented fuzzy control system shows enhanced and better performance when compared with one without a controller, a proportional-derivative (PD) controller, and a proportionalintegral-derivative (PID) controller

Development of hybrid force-position controller for ultrasound-guided breast biopsy robotic system

Conventional ultrasound-guided breast biopsy (UGBB) procedure is commonly performed to assess abnormal masses within the breast. It requires a radiologist to handle multiple devices at once, which could reduce the abilities in performing such procedure resulting in radiologist’s fatigue, compromised breast tissue due to multiple insertions and susceptibilities to pneumothorax complication for the patient. Previous studies have reported that many of the restrictions associated with handheld minimally invasive methods were tackled when physician assist instruments were used. Therefore, the purpose of this research is to assist radiologist in conventional UGBB procedure by introducing a semi-automated robotic system to maintain desired contact force between the ultrasound transducer and the breast. For that reason, a hybrid force/position controlled UGBB robotic system has been developed in simulation environment. The UGBB robotic system involves a 5 degree of freedom (DOF) articulated robot arm to control the transducer movement, a force/torque (F/T) sensor system to measure the contact force, an ultrasound machine to view the inside structure of the breast tissue and a computer-based control system. As such, the RV-2AJ robotic arm has been modelled with its positional accuracy of almost 100%. A breast model based on a medical grade breast phantom has been established with a mean error of 0.69% by using black-box modelling approach. Motion disturbance from human respiration has been explored as well since it plays a significant element that would affect the stability of the system to constantly maintain low contact force on the breast.Finally, intelligent Fuzzy-PID hybrid force/position controller has been successfully established to maintain low contact force on identified breast stiffness characteristics. The overall hardware-based simulation shows promising outcomes with almost no overshoot, fast rise time, high robustness and stability on different environment condition. In conclusion, the success of this work serves as significant foundations for long-term related research, especially in the development of UGBB robotic system and approaches of force control mainly for human-robot interaction

Continuous data collection of under extrusion in FDM 3D printers for deep-learning dataset

A shortcoming noted in fused deposition modelling (FDM) 3D printing technology refers to lack of intelligent monitoring and intervention during the printing process. Fail prints can still occur during the printing procedure even though the printer is of industrial grade and far more expensive than that of hobby grades. Under extrusion has been determined as one of the frequent failures in 3D printing. Such failure stems from insufficient extrusion rate and/or inadequate melting temperature of filament during the print. Under extrusion failure may result in undesired layer gaps, missing layers, unbalanced layers, and even holes in the printed models that would make the models completely unusable. Hence, an effective method that can reduce waste materials and overall costs is by integrating artificial intelligence (AI) into 3D printers. However, a large dataset is required prior to the training process of deep learning. Hence, this study proposes an automated and continuous data collection of under extrusion samples in FDM 3D printers using Raspberry Pi and webcam. As a result, adjustment of the G-code of the standard tessellation language (STL) models and repeated process of printing 3D models can effectively achieve the desired images

Development of a dodecacopter using Pixhawk 2.4.8 autopilot flight controller

This research focused on the development of unmanned aerial vehicle (UAV) of a dodecacopter system. The dodecacopter is controlled through a Pixhawk 2.4.8 firmware�based flight controller. The communication between the dodecacopter and flight controller is connected through wireless communication system. The dodecacopter is well equipped with latest technology from Pixhawk flight controller for efficient and smooth controlling system. The dodecacopter balancing system is using the technology of barometer MS5611 and magnetometer IST8310 sensors. The developed dodecacopter is equipped with 12 Tarot 4006 brushless motors to increase the payload capability. Based on the results, the experiment shows that the dodecacopter can hover and maintain its position with optimum stability. Observation shows that the dodecacopter performances can be increased by using high-powered motors, lighter batteries

Intelligent approach to Force/Position Control of Ultrasound-Guided Breast Biopsy Robotic System

Large deformations occur inside the breast whenever the biopsy needle is inserted during conventional ultrasound-guided breast biopsy procedure. Inconsistent force from manual handling of the ultrasound transducer makes maintaining the suspected lump in the ultrasound-imaging region challenging and further position the patient at discomfort. Hence, this research presents the development of force controller for an ultrasound-guided breast biopsy (UGBB) robotic system in the aims to alleviate said issues by maintaining low contact force on the breast. A variant of force controllers has been studied; proportional (P), proportional and integral (PI), PID, PI-Fuzzy, Fuzzy-PID (F-PID), and Fuzzy-PID using Lookup Table (F-LUT) controllers. Effect of external disturbance such as subject respiration is considered to see the reliability of each developed force/position control system. Based on the simulation results, F-PID force controller shows promising outcome with a marginal error of 0.33% during the disturbance period and no error when the disturbance is absent