Design and structural analysis of a 6-axis industrial robotic arm

The master's dissertation presents the conceptual design for a six-degree-of-freedom robotic arm for the automation of battery replacement in UAVs used in the agricultural sector. Due to their relatively short UAV flight times, battery changes are quite frequent, but such changes are detrimental to continuity in operations as well as overall productivity. The conceptual robotic-arm design was done in 3D using SolidWorks, while the robotic-arm's performance under real-life scenarios was determined using transient structural analyses done on Ansys. There is a custom-engineered cycloidal gear system in place at every robotic arm joint for achieving higher torque outputs, reduced backlash, and a compact spatial structure. The modular robot structure increases the robot's versatility for several UAV applications and allows for a range of operational needs. The material choice was made in order to provide an optimal balance between strength, weight, and manufacturability, and the resultant structure is made from an outer shell in the material grade aluminum A356 and internal structures made in 1.8550 steel. The end-effector is provided with a pneumatic-actuated gripper capable of gripping battery packs weighing as much as 12 kilograms. The inverse kinematics solutions, dynamic simulations, and transient load analyses provided findings that supported the structural soundness, small displacement, and high accuracy of the robotic arm. The findings all confirm the effectiveness of the system in realistic applications, making it a viable and novel methodology for battery replacement automation in unmanned aerial vehicles in agriculture.