Cherie Kinoshita was born and raised on the beautiful island of Oahu in Kaneohe. She is a sophomore at the University of Hawai’i at M?noa planning to major in Mechanical Engineering with a minor in Mathematics, and hopes to be a project manager. She loves sports, especially basketball and soccer. Not only is she a student at the University, but she loves to be involved with the community and is an assistant coach for a high school varsity girl’s basketball team. Sports, science and math are her passions.
Home Island: Oahu
Institution when accepted: University of Hawai’i at M?noa
Akamai Project: Building and Mounting a Strain Gauge on an Antenna
Project Site: Smithsonian Submillimeter Array (SMA)
Mentors: Billie Chitwood & Robert Christensen
The antenna at the Smithsonian Submillimeter Array (SMA) is held up with the aid of counterweights. These counterweights might cause a problem during operation when they pass over an access door, located at the base of the antenna. This could affect the way the antenna points, causing a “potential weak spot” in this area. The goal of this project was to set up, mount and test strain gauges to measure this “potential weak spot,” to see if these counterweights do affect the pointing. The resistance of a strain gauge, a type of sensor, varies with applied force. As an object is deformed, the foil on the strain gauge deforms, causing the electrical resistance to change. After designing and testing a model in the lab, the four strain gauges were then mounted on the SMA antenna. In order to determine the resistance change, the strain gauges were connected in a full Wheatstone Bridge configuration and set up as a shear strain arrangement. This is to determine the angular distortion of an object under stress. As a result, the effects of the counterweights can be quantified. Data will be presented showing the amount of strain over the access door area and how much the counterweights affect the pointing of the SMA antenna. This strain gauge will help with future observations with the antennas and increase antenna accuracy.