Product

Overview

     It is a RobotEx corporate standard to have an entire product designed and evaluated using SolidWorks CAD software before any materials are cut, in order to ensure precision and eliminate waste.

     The design of the CPU construction robot developed through separate subassemblies which combined to form the robot. Locally, Austal Shipbuilding employs a modular manufacturing process which RobotEx emulated with the subassembly design process. In order to be efficient, RobotEx began construction on finalized subassemblies while the design process continued simultaneously on other subassemblies.

     This year, RobotEx used a Kickstarter account to raise funds for the team. Birmingham design firm, Bates Corkern, purchased the naming rights for RobotEx's 2013 design. They chose to name it Andreas. Andreas comes from a Greek word that means "man warrior". It is a fitting name because we are the Davidson Warriors.

     With the release of Andreas, RobotEx reached new levels of efficiency and safety while updating a CPU for BEST's robot, Squeaky. RobotEx continues to employ a systematic engineering process in the creation of its products. Through the incorporation of brainstorming and redesign processes, the manufacturing techniques of the company are now more precise than ever. RobotEx made many decisions in the design of Andreas. The company's choices (on the side) are outlined in green.


AndreasFlow Chart

Arm

     The arm was designed to grab and lift the CPU parts accurately and provide the necessary extension to sort the various CPU parts into their appropriate receptacles. Three possible solutions-a gear-driven arm, a pulley system arm, and a wheel-driven arm-were presented and voted on based on four criteria: reliability, ease of fabrication, maneuverability, and power.

     The arm is made of two pieces of pine wood connected with two igus tracks. The entire arm is connected to a driven gear. The claw attaches to an igus rod at the end of the arm. The motor attaches to the wrist mechanism.



ArmActual Claw

Wrist

     RobotEx designed the claw with a wrist so it could flip the transistors and turn them into NAND gates. A small motor powers a gear which operates the wrist. RobotEx chose to use this gear system because it allowed for greater than 180° rotation. RobotEx implemented a small motor instead of a servo because the motor had 9.49 in-lbs of torque as opposed to the servo's 3.49 in-lbs of torque. The gear system of the wrist has a 7:16 gear ratio to allow for efficient use of the force created by the motor. RobotEx calculated the force this gear system could exert to lift the claw and the live load. The system is able to lift 7.59 pounds, which is more than sufficient to lift the weight of the live load and the claw, which is 1.58 pounds. The figure on the right shows a SolidWorks render of the wrist and claw.



Wrist

Claw

     RobotEx designed the claw to perform all the functions required to build the CPU. The claw has a wrist that bends vertically 180 degrees with the use of a gear and a driver gear attached to a motor. Attached to the wrist is a parallel gripper operated with a servo-powered driver gear which turns two larger gears. The team chose to use the parallel gripper because of information discovered during the brainstorming process. RobotEx then considered the optimum materials with which to build the claw. One criterion for the claw was that it would hold the game pieces without dropping them. The team used friction tests to discover which materials would best prevent slipping, and selected foam for the fabrication of the gripper padding.



Claw

Tower

     The tower consists of four pieces of ½" plywood, for stability. Its primary function is to serve as a base for the arm. Two holes support the pivot, and bearings in these holes smooth the motion of the arm. The tower also acts as protection for the cortex and wires.



TowerActual Tower

Base

     The design for the base accommodates the necessary 360 degree rotation of the arm. The arm rests on a rotating, rectangular platform that rises from the base. The platform rotates on a driver gear with a large motor and a lazy Susan. The base and the platform are constructed of ¼ in thick plywood. The base is 23 inches long and 19.75 inches wide so it can fit on the trolley. To stabilize the base and facilitate clipping it to the trolley, 4in by 3.5in pieces of lauan were attached to each bottom corner of the base.





BaseActual Base