Team Bazinga [Automated Underwater Lifting Bag]

Automated Underwater Lifting Bag

In order to find a safer method for recreational divers to recover small submerged object, Bazinga Team, a senior project design group from the California Maritime Academy, designed and built an automatically ascending, double lift point, self-contained lifting device. The concept stems from the manually operated lift bags used for recreational diver salvage. This project will allow divers a hands-free method to execute salvage operations. A number of methods were discussed for accomplishing this task. The method chosen consists of a control module attached to a scuba tank that will supply input air for two lift bags and discharge air from the bags using a pneumatic actuator. A pressure sensor and accelerometer are used to input values to an Arduino that are needed to determine rate of ascent and orientation of the object being salvaged. This device is being developed to operate at approximately 100 ft, which is the safe limit for recreational divers. The composition of the device includes a number of off-the-shelf components for ease of acquisition, cost, and assembly. The internal components of the control module will include operating valves for the air system, an Arduino, a control circuit board, a pressure sensor, batteries, a start switch, and an accelerometer. The components external of the cap and tube style module, are the tank and regulator, air lines rigging gear and the lift bags. The lift bags will include pneumatic actuators mounted to the dump valves. The device is in the prototype stage for the purposes of the academic requirements. The team fabricated many of the parts in the device, while the rest were purchased, installed, and function tested. Many issues had to be managed to be ready for pool testing. Watertight integrity was determined as well as electromechanical function. Control issues were resolved by building addition branches of the electrical circuit, particularly in the case of adapting the pressure sensor resolution into a usable range for the scope of the project. The device was tested in the CMA pool. While the electromechanical testing in the pool was satisfactory, there were resource constraints that prevented the necessary testing to get a satisfactory test of the control system. The project group is planning to develop a 2nd iteration after graduation.

A project submitted to the Department of Mechanical Engineering in partial fulfillment of the requirements for the B.S. degree. Department of Mechanical Engineering ME 494