Low alloy steel susceptibility to stress corrosion cracking in hydraulic fracturing environment

Ezechukwu J. Anyanwu


This thesis describes the development of a real-time, open source, easily programmed and controlled platform to replace the existing Manoi AT01 humanoid robot. Processing language was used as a control and implements the Graphical User Interface (GUI) and an Arduino Mega development board and an SD21 servo-driver were used to implement the controller and data acquisition.The designed platform is also used to measure and calculate the Center of Pressure (CoP) of the robot. For this purpose, Force Sensitive Resistor (FSR) sensors are used to measure the force exerted by the weight of the robot. Four sensors were used and are positioned on the corners of a specially designed plastic feet attached to each leg.The CoP is calculated by the Arduino and displayed in real time on the GUI.In order to determine the Center of Mass (CoM), the Statically Equivalent Serial Chain (SESC) model is adopted. This model is implemented using MATLAB. The implemented GUI provides a function that allows the user to create a file for storing the position of each servo and the CoP of different scenarios. These data files are used as the input to the SESC model program in order to estimate the CoM of the robot.