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DrD

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DrD last won the day on October 13

DrD had the most liked content!

About DrD

  • Rank
    Member

Profile Information

  • Gender
    Male
  • Location
    Iowa, USA
  • Interests
    Kinematics, dynamics, mechanics of materials, Theory of Machines, machine design, vibrations
  • Present Company
    Machinery Dynamics Research
  • Highest Qualification
    PhD
  • Engineering Qualification
    Registered Professional Engineer, TX, WI (Ret'd)

More Information

  • Achievement /recognition/ Certifications
    Consulting work for a variety of industries, particularly in the IC engine related area (Torsional vibration analysis, shaking force analysis, engine cam design, system simulation).

    Author of several books, including one widely used textbook for Theory of Machines.

    Life Member ASME
    Member SAE
    Member SNAME

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  1. It is possible that I may be able to help you, but again, I may not. Please answer a few questions for me. 1) What college level math courses have you taken? 2) What college level mechanics courses have you taken (statics, dynamics, vibrations, theory of machines, etc)? 3) Where are you located? 4) Are you able to pay for tutoring? DrD
  2. DrD

    Boring of automobile parts

    So, what is your point? Is this written to inform, to ask a question, or for just what purpose? DrD
  3. A brake is a brake is a brake. Any brake has the potential to stop any rotating object. Whether it is a good idea or not is another matter, but certainly an automotive caliper brake has the potential to stop a winch drum. You really need to learn the difference between "brake" and "break." They are entirely different words, even though they sound alike in English.
  4. DrD

    Inspection of automobile shaft parts

    So, is this intended as a question, a statement of fact, or what?
  5. Wow! That was one boring video! I could not stay interested enough to watch it to the bitter end. The whole idea seems ludicrous. If you want to generate energy by human effort, why not apply it directly? Perhaps simply ride a bicycle, rather than try to generate electric power by pushing things. Talk about grasping at straws ...
  6. I rather doubt that you will ever get to the point where you fully understand the problem. Most of us find that there is always something more we can learn. At the same time, it seems foolhardy to commit to designing something about which you know so little. There is nothing about which I know everything, yet I would undertake to design some things but not others. I would design those things about which I already know enough to make a good start. I would avoid attempting to design something about which I now know nothing. Do you see the difference? DrD
  7. DrD

    Defense products

    What a fabulous post! Not a complete sentence in it, just a string of terms describing destruction and destructive devices. This makes no sense at all, so it is posted in exactly the proper place. DrD
  8. What a great idea to commit yourself to a project you know nothing about! This is utter foolishness!! Engineers do not do such things. DrD
  9. DrD

    Kinematics of Machines

    What are Z-Kinematics U-Kinematics? I've never heard these terms before, so I'd be interested to know what you are talking about.
  10. DrD

    Two Short Math Problems

    I really don't think I can help you. I don't know much about robots. DrD
  11. Why in the world do you want to put a flywheel on a DC motor? The purposes of a flywheel are (1) to smooth out irregularities in the rotational motion of the shaft (torsional vibration), and (2) to store energy in order to continue operation though a power interruption. You did not mention either of these, so I ask again, "why do you want to put a flywheel on a DC motor?"
  12. "It gives balance to engine and load is uniformly distributed in crankshaft." This statement is totally incorrect. Torque is delivered to the crankshaft as a series of pulses, in no way uniform. In a multicylinder engine, torque will be positive at one location while it may be negative at another. What is a "four stage engine"? Do you mean four cylinder, or perhaps four stroke, or something else? All the pretty animations in the world are not worth much if the accompanying statements are nonsense. DrD
  13. The PDF file below will show you how to solve this problem. DrDPlanetaryProb.pdf
  14. As a starting point, you must know the MMOI for each individual component; without that, you cannot begin. Assuming that the individual component MMOI values are known, do a kinematic analysis of the planetary train to determine the velocity of the CM of each component. The use that information to formulate the kinetic energy of the entire system, all moving according to the kinematic relations. You will have to choose some rotation as a reference value, usually either the input or output rotation. The kinetic energy will have the form T = (1/2) theta-dot^2 (term1+term2+...+termlast) where theta is the reference rotation. The sum of terms indicated is the effective MMOI for the gear train. DrD
  15. DrD

    Two stroke &four stroke

    So, what else is new? DrD
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