Alternative Solutions

The alternative solutions cover  how to power the mechanical claw and the shape of the claw to accomplish the tasks of the MATE ROV competition. Three power resources taken into consideration when creating the alternative solutions were hydraulics, an electric motor, and a servo. In addition, the shape of the claw was designed to the tasks provided by the competition, specifically the tasks involved with collecting samples of crustacean species, bacteria mats and resurrecting Hugo's frame.

Alternative Solution #1

The first alternative solution utilizes an electric motor to power the mechanical claw open and closed. The motor directly connects to the idler gears, which are located inside a cage measuring 6" in length by 4" in width. The idler gears will have 2 gears on one side of the 1" big gear and 1 gear on the other. In this solution, the speed ratio that the mechanical claw will open and close will be the same because the two gears on the same side will measure 1/2" each, while the single gear on the opposite side will measure 1/4". A 1/8" spindle gear will connect to the motor before the 1" big gear to lower the ratio. The claw will be constructed in a shape that has a pronged segment on the bottom to pick up objects and a rectangular shaped segment on the top to lock the objects in place.

Alternative Solution #2

The second alternative solution also utilizes an electric motor to power the mechanical claw as it does in the first solution. The cage containing the gears will be a square measuring 4" on each side. A 1/8” spindle gear will connect directly to the motor, so it will spin at the same speed as the motor. A 1” big gear behind that will be used to lower the ratio to one that is slow enough to operate the claw effectively. A 1/8” gear will be on one side of the big gear and two 1/2” gears will be on the other, separated by the pivot point. The claw will close much faster than it will open because the ratios on each side are not the same. The mechanical claw will be 8” long and consist of two half-circular shaped cups that will come together. The size of each cup will be 4” in length and 2” in depth. The fulcrum of the claw will be constructed distant enough from the cups so that the objects will not be forced out in the opposite direction when being picked up. In addition, rubber will be inserted on the lip of each circular cup to add traction. 

Alternative #3

  The third alternative solution requires a servo for a power source to make the mechanical claw function. A servo is a specific type of motor that consumes little energy because of its size. Servos have built in control circuitry. In this solution, a servo will power the claw to close, which remains open during all other parts of the competition until needed. The servo motor will be attached to the pivot point of the claw with a metal wire. The claw on this solution will be the same design as solution 2, but smaller in length. The two segments from the pivot points to the circular cups will be 3” as opposed to 5”. The location of the fulcrum on the claw will be constructed at a distance far away enough from the cups so that objects will not be forced out the front when the two claws converge.

The three alternative solutions consist of two different power sources, which are the electric motor and the servo motor. Solution 1 and solution 2 have variations of gear sizes. As a result, solution 1 operates on an even gear ratio, while solution 2 closes faster than it will open. Despite using less power, solution 3 is also a viable option. It utilizes a servo motor to close a mechanical claw that is a scaled down version of the claw implemented in solution 2. Both types of mechanical claws used in the three alternative solutions were designed based on the principle of shoveling the objects.