The design development and tests of an experimental nodule collection vehicle are presented. The prime objective of this effort was to construct a test vehicle which could be used to predict the nodule collection performance of a commercial deep ocean mining machine and provide data for the prediction of the vehicle dynamics and verification of analytical tools.
To produce an optimum design that meets these objectives, a series of extensive land-based testing and trade-off analysis was performed. The final version of an experimental vehicle, measuring 23 feet in length, eight feet in width and six feet in height, and weighing seven tons, was heavily instrumented to acquire engineering data to aid in the design of a commercial mining machine.
Until a few years ago the technology for collecting manganese nodules from the ocean floor was practically unproven with the state of the art limited to tow tank-tested devices. In early 1973, a program was initiated by Kennecott Exploration, Inc., to develop a collector vehicle system which could be lowered from a suitable support vessel to the bottom of the ocean and then towed to collect nodules.
The KEI Model V collector vehicle resulted from this development effort. The collection system, measuring about 23 feet in length, eight feet in width, and six feet in height, weighed seven tons and was heavily instrumented to acquire engineering data to use in the design of a commercial nodule mining machine. The vehicle was designed for towing over a selected pre surveyed area of the ocean floor at depths ranging from l3,500 feet to 20,000 feet; a special steel armored electromechanical power cable provided mechanical and electrical connection with the surface ship. The nominal tow speed range was from zero to ten feet per second.
The front section of the vehicle was designed to be capable of accommodating small and medium sized obstacles or surface irregularities up to four feet high in any possible roll position, and the general shape of the vehicle was such as to permit self righting in case of turnover due to obstacle encounter. All vital parts and components were protected by means of a removable semicircular sheet metal enclosure which also allowed access for adjustment of the vehicle's surge mass (see Figure 1).
The major objective of the Model V test vehicle design was to create a structural and mechanical assembly which, within defined weight, dimension, and mass property constraints, would provide suitable characteristics to assure the following functional requirements:
to support functional and navigational sensors
to accommodate encountered obstacles on the ocean floor
to be a mechanical test bed
to provide needed physical parameter measurements for prototype collector design data
to collect and retain nodules
The prime objective of the test was to demonstrate the feasibility of a towed suction-type collector system.
