Our next project is to make a rubber band powered rowing boat. I guess you all familiar with the rowing or rowing boats. Rowing boat is not a complex boat and basically one or more people can drive. A seated rower pulls on one or two oars, which lever the boat through the water. The pivot point of the oars (attached solidly to the boat) is the fulcrum. Normal rowing boat has a human rower but in our case we replace the rower with the rubber and simple lever system to give power to the boat. You need to wind the rubber band and then release it to move forward. Let’s see how we can make this rubber band powered rowing boat. Later I will explain how we can replace rubber band with a small electric motor. Once you place a motor you can even control this boat using radio controlled remote controller.
Rowing Boat DesignFirst thing is to make the body of the boat. You can us either wood or plastic material for this. Here I have used rectangle shape, but that is not always constant you can have any shape you want. Only thing is the body of the boat should float on the water. As shown in the figures 2 oars need to make. I am not going to specify the length for these oars, but it should large enough to drive your boat body. Then you need two pulleys, a rubber band, two fulcrums and carpentry glue. If you are not familiar with carpentry work, better get help from someone familiar with. Always please refer the figures to better understanding. Next thing is to fix two pulleys to the edge of the wood or plastic cylinder. You can use small PVC pipe as the cylinder. Paste two pulleys on the edges of the cylinder using carpentry glue. Then make a small hole in the middle of the cylinder and place rubber band through the hole and tie it. As shown in the figure you need to place your two pulleys with the body. Once you done these pulleys should rotate freely. Then take the free edge of the rubber band and fix it with the body of the boat using a small nail. Fix two fulcrums to body as in figures and fix two oars on pulleys through fulcrums. Now if you rotate a pulley, two oars should work like how human rower drive oars.
Now almost done, we are going to test our rubber band powered rowing boat. While keep body of the boat fix, rotate two pulleys backward till rubber band get stretch enough. Then place the boat on the water and release pulleys. Now you can see that once you release the pulleys, because of rubber band pulleys get rotate backward, then oars of are also rotating. Then oars hit with the water, boat get move forward. Until oars are rotating boat get move forward continuously. You need to make sure that both two oars should rotate equal angel otherwise boat might not move forward and it will rotate here and there.