“The Big Dipper”

Software We have created an executable code that can drive the device and record test data on any computer. This was achieved through the combination of LabVIEW Developer, MathScript, and Matlab.

Slide Rail & Caliper Connected by a cross bracket, the slide allows the lens to move in and out to change the dipping radius and the caliper displays that radius to +-0.005mm.

Fluid Bin Custom made bin to provide the lens coating . The bin has a laser etched fill line on the inside, and can store up to 2 liters of coating fluid. For safety purposes , it also has a custom made lid.

Base Structure Two level structure that contains all the mechanical and electrical components. The two plates and supports are welded together to increase stability and strength.

Linear Actuator Non-captive, stepping, linear actuator is used to provide the necessary force to perform the dipping motion.

Controller (Arcus) Single axis combined driver and controller with micro step capability. Analog and digital I/O ports along with USB communication.

Accelerometer Piezo-electric type with liquid resistant shell and cable. Measures AC acceleration due to vibrations which may invalidate test results.

Sensors and other Important Features Additional features include; an encoder on the linear actuator, thermocouple for the solution, centering laser, spill guard, limit switch, and adjustable rubber feet.

Arc Dip Coating Wesley Alexander, Naftali Hirschberg, Melvin Yip, Robert

Reynolds, Kristin Dicikiyan Sponsor: Essilor of America

Department of Mechanical Engineering MECH 4382 - Spring 2015

Project Overview

Background Information Essilor is the leading innovator, manufacturer, and wholesale distributor of optical lenses in the United States. Essilor R&D produces many unique lens coatings including anti-reflective layers which are applied through a very expensive vaporization process with precise but brittle results. A dipped (wet) coating would be cheaper and stronger, but the curves on a lens cause imperfections. A radial dipping method has been proposed.

Problem Statement • Create an R&D tool to test the theory of radial dipping as a means to produce

smooth and even coatings on a lens. • Allows for repetitive testing with varied parameters such as radii, velocity, and

acceleration. • Provide accurate system feedback for cause and effect comparison of results

System Requirements

Program Description Special Thanks and Gratitude To…

Arnaud Glacet – Essilor Sponsor Dr. James Hilkert – Faculty Advisor

Others Essential to the Success of the Project…

Dr. Robert Hart, Gene Woten, Nancy Finch, Dr. Hongbing Lu, Darren Bravenec, and Thomas Judge

• Maintain an even contact angle between the lens and the coating solution

• Linear velocity of lens: between 0.5 to 10mm/s

• Linear acceleration of lens: ±0.1 to 1mm/s²

• Record kinematic data such as position and velocity • Able to operate on any computer with an executable

program • Labview compatible with a user friendly GUI • Employs existing lens holders • Table top size and corrosion resistant • Reservoir contains between 1-3 Liters of solution • Easy to operate and maintain • Adjustable to preserve accuracy during tests

• User Input Parameters: Lens Diameter, Dipping Radius, Velocity, and Acceleration.

• GUI developed in LabVIEW • Enter in the user parameters to Matlab file. This calculates a

custom motion profile into a velocity array. • LabVIEW directs ARCUS controller to move motor forward at

a constant speed and wait. Run time is calculated to dip the lens. Once the wait time is over, return to initial position.

• As the motor returns to its initial position, follow velocity array for desired profile.

• The device will collect and store encoder information during test

Final Design Features