Team Uno 9/30/04 Stephanie Rohrs Chuck Smith Mechanical Actuation Systems

To achieve our objective, the SmartShade will have two mechanical actuation systems. The first, Joint 1, is located in the base of the umbrella and is responsible for rotating the entire umbrella 360º. The second, Joint 2, is located roughly 4’ above the base on the pole and is responsible for tilting the top of the umbrella from the vertical position to 60º from vertical. System Overview

Joint 1 Requirements: 1. Must support weight of umbrella and wind loads experienced during use (25 mph). 2. Must fit inside base cover. 3. Must provide enough torque to turn umbrella against 25 mph wind. 4. Must allow rotation of 360º 5. Must rotate umbrella at a minimum speed of 1/3 rpm.

Joint 1 Possible Solutions: Idea #1: Mount motor directly underneath pole. Advantages: 1. Simple Disadvantages: 1. Tough to support load 2. Very little mechanical advantage, would require a motor with a LOT of torque

Joint 1 Possible Solutions: Idea #2: Mount motor to side of pole and build gear train. Advantages: 1. Possible to have high mechanical advantage, motor could be smaller 2. Easier to support load Disadvantages: 1. More complicated

Joint 2 Requirements: ● Must provide enough torque to turn umbrella against 25 mph wind and maintain position. ● Must rotate umbrella at a minimum speed of 120º per minute.

Joint 2

Possible Solutions: Idea #1: Mount motor directly to top pole. Advantages: 1. Simple 2. Reduction of parts Disadvantages: 1. Must resist immense shear stresses 2. Must produce/resist a high amount of torque 3. Cannot be mounted in pole, must be mounted outside.

Joint 2 Possible Solutions: Idea #2: Slider-Crank configuration driven by linear actuator. Advantages: 1. High mechanical advantage 2. Easy to resist stresses/torques 3. Prefabricated 4. Can fit inside pole/Look pretty Disadvantages: 1. Cost 2. Ability to control

Joint 2 Possible Solutions: Idea #3: Slider-Crank configuration driven by custom power screw. Advantages: 1. High mechanical advantage 2. Easier to resist stresses/torques 3. Can fit inside pole/Look pretty 4. More cost effective 5. Custom built for this application Disadvantages: 1. More complicated 2. More fabrication required