Document Type

Restricted Campus Only

Publication Date

4-30-2013

Abstract

Executive Summary The main goal of this design project was to develop a system capable of receiving used resistors from the electronics lab, straighten their leads, and sort them according to nominal resistance value. In order to accomplish this goal, the team designed and built a system composed of five modules: the input module (or input module), the primary straightener, the secondary straightener, the sorting module, and the "smart" ohmmeter.

The main function of the input module is to limit the amount of bend that the leads are allowed to have and guide resistors into the next module. It is composed of two small u-shaped walls facing each other, forming a rectangular cross section that encloses the body of the resistor, with r two slots along the short sides of the rectangle fom where the leads protrude out. The primary straightener utilizes lateral linear motion align the leads with the central axis of the resistor body.

The secondary straightener is composed of a rotating plastic capable of rolling the resistors leads against a concave wall positioned close to the cylinder, eliminating kinks. The "smart" ohmmeter (which connects to the resistor leads through the primary straightener) is responsible for determining the nominal resistance of each resistor, by measuring the exact value and categorizing each measured resistance into a category defined using an internal algorithm. The sorting module is composed of a rotating "lazy-susan-type" disk containing different bins, which rotate into place based on the measured nominal resistance value of each resistor.

Prior to integration, each module was separately built and tested. The input guideway was tested by providing force to the lateral metal walls to verify the required strength and by manually introducing resistors with various lead configurations. The primary straightener was tested by manually operating the device and straightening ten randomly selected resistors from the "used" bin in the lab. The secondary straightener was tested by straightening 10 resistors previously straightened by the primary straightener. The ohmmeter was tested by comparing readings of resistors across the spectrum of possible values to their respective nominal resistances given by the color codes. Finally, the sorting module was tested by connecting it to the programmed microcontroller, and allowing it to rotate to the correct position after reading the resistance of different resistors across the spectrum of possible values.

All modules work correctly and physically fit together. However, testing of the overall system was not possible due to wiring and programming issues associated with integration.

Comments

Dr. Diana Glawe, Course Instructor

Dr. Leifer, Advisor

ENGR-4381

Download

Share

COinS