Get access to thousands of free CAD projects

Join our community of over 1,540,000 engineers and 530,000 CAD files

This is my entry to the challenge.

It's a concept based on the movement of a socket wrench. I chose to dwelve into this movement rather than a crank, because I believe it is more of a natural movement for the human arm.

Also I believe humans are far more familiar with this "lever" movement. We deal with it everyday, be it a door knob or a car hydraulic jack.

The table has a height adjustable between 650 and 1050 mm, and it requires less than 10 kgs of force to move the maximum allowed weight (500 kgs as per instructions).

Comments:

  • Chris Duncan
    Chris Duncan over 2 years ago

    Leandro,

    It sounds like you have it well thought out.

    Only one thing I will add then. You have to "read between the lines" of the challenge requirements. If you calculate 500kg @15mm/s it is physically impossible to achieve with average manual power, and one of the requirements is that a person of less than average strength can meet the speed requirement. Remember we are talking about power here, not force. The application of force over distance and time.

    Spring assist may be the only way. Erkki of Sovella left a comment in the discussion on the challenge page.

    ""I feel that it is quite difficult to meet the hand force, weight and speed requirements without energy storage (spring) or a weight balancing system; it is heavy to lift 500kg with speed 15mm/s. My guess is that an engineer, who has good solution for that part of the challenge, has good opportunity to win.""

    ""Somebody asked something about hand force calculations. Because we have to choice the winner without prototype, a theoretical calculation is needed to evaluate needed hand force.""

    I think what he really means here is not only a force calculation , but also a watt (power) calculation.

    Here are some gas springs with download cad files
    http://indgassprings.com/pages/prod_c_size.html

  • Kaspar Kiis
    Kaspar Kiis over 2 years ago

    Thank you for participating in the contest. GrabCAD has announced the results. Have a look: http://grabcad.com/challenges/table-height-adjustment-mechanism-challenge/results

  • Steve Lu
    Steve Lu about 1 year ago

    Great idea!

Please log in to add comments.

Log in

Save Cancel