undefeatfencer
Feb 25, 2014, 02:08 PM
Hello,
I am currently in high school taking a class in mechanical engineering. My teacher has assigned the class a project, that being to build an underwater ROV that must perform two tasks: It must have the ability to pick up various types of objects, and it must turn two valves shut in order to stop a leaking air (simulated oil) line; all of this must be accomplished while only viewing our actions through an onboard camera. The first task was easy to find a solution to (scooping/hooking), as for the second solution, my team members and I devised a plan to take a "high-torque" motor, attach a plexiglass plate perpendicular to the shaft, with skinny nails fixed with epoxy in order to turn the valves. Now, after spending many headache-filled class periods watching/playing around with CAD as my "expert in AP Physics" team member tried to find the right motor we would need to get, I have decided to research torque and perform the calculations myself. Unfortunately, this has proven to be fairly difficult as I have a limited background with physics and will not be taking AP Calculus until next year. We have already been given small DC motors to use as thrusters, however, when I tested these, they were easily stopped with the smallest of applied forces, and therefore would not be ideal for my application. The valve in question is a "standard" outdoor hose/spigot valve; metal, with semi-triangular cutouts running through the thickness of the valve. My instructor told me that once I figure out how much torque I needed, he might be willing to loan me, or buy me a motor to fit our needs. The motor does not have to have a high RPM, as the valves fully open/close with 1.57 full revolutions, and, as the RPM rate increases, so does the price of the motor - I have noticed. I am not necessarily looking for a spit-back answer, but more a demonstration/explanation of how to figure out the information I need, as I do recognize that I must learn the material and not just "copy and paste" the answer of someone else. If someone could please help me figure out how the equations etc. work that would be most appreciated.
I am currently in high school taking a class in mechanical engineering. My teacher has assigned the class a project, that being to build an underwater ROV that must perform two tasks: It must have the ability to pick up various types of objects, and it must turn two valves shut in order to stop a leaking air (simulated oil) line; all of this must be accomplished while only viewing our actions through an onboard camera. The first task was easy to find a solution to (scooping/hooking), as for the second solution, my team members and I devised a plan to take a "high-torque" motor, attach a plexiglass plate perpendicular to the shaft, with skinny nails fixed with epoxy in order to turn the valves. Now, after spending many headache-filled class periods watching/playing around with CAD as my "expert in AP Physics" team member tried to find the right motor we would need to get, I have decided to research torque and perform the calculations myself. Unfortunately, this has proven to be fairly difficult as I have a limited background with physics and will not be taking AP Calculus until next year. We have already been given small DC motors to use as thrusters, however, when I tested these, they were easily stopped with the smallest of applied forces, and therefore would not be ideal for my application. The valve in question is a "standard" outdoor hose/spigot valve; metal, with semi-triangular cutouts running through the thickness of the valve. My instructor told me that once I figure out how much torque I needed, he might be willing to loan me, or buy me a motor to fit our needs. The motor does not have to have a high RPM, as the valves fully open/close with 1.57 full revolutions, and, as the RPM rate increases, so does the price of the motor - I have noticed. I am not necessarily looking for a spit-back answer, but more a demonstration/explanation of how to figure out the information I need, as I do recognize that I must learn the material and not just "copy and paste" the answer of someone else. If someone could please help me figure out how the equations etc. work that would be most appreciated.