Announcement

Collapse
No announcement yet.

Summary of Foam Coefficient of Friction

Collapse
This topic is closed.
X
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Summary of Foam Coefficient of Friction

    Biomch-L,

    Following my original question is a summary of replies. Thank you to those
    who replied. However, there seems to be little information on contact
    between foam/compressible/rubber like materials and human skin. The
    material properties for EVA displayed on the web (www.matweb.com) seem to
    concentrate on moulded/extruded resin grade materials.There are quite a few
    listed polyurethane, polycarbonate and polypropylene foams but most state
    that they can custom formulate the foam and vary the physical properties
    (coefficient of friction, abrasion resistance, hardness and density) to
    suit various applications and therefore do not provide a value. I thought
    there may be enough sports around (including water sports) that require
    padding as well as surface testing that may have included this type of
    investigation.

    Regards,
    Justin

    Original Question:
    >Biomch-L Colleagues,
    >I have been looking at Ethylene Vinyl Acetate (EVA) foams used as a soft
    >padding on certain water sport equipment.There are also certain types of
    >Polyethylene (PE) that are used. I was looking to find an estimate of the
    >coefficient of friction between these soft, 'rubberised' foams and the
    >human foot in both wet and dry conditions. I have searched on the net with
    >little success and most literature that I have found on these type of foams
    >lies in the footwear field and thus the coefficient of friction studied is
    >the footwear to surface interface rather than the foot to foam interface. I
    >was wondering whether anyone knew of any research that might help me.
    >Your help would be greatly appreciated and a summary will be posted.
    >
    >Thanks,
    >Justin


    RESPONSE 1:
    Justin,

    www.matweb.com has everything you'll every need to know about material
    properties
    I did a search for Ethylene Vinyl Acetate and got 175 types.
    Ethylene Vinyl Acetate Copolymer (EVA), Extrusion/Coating Grade
    has a coefficient of friction of 0.63

    hope that helps
    Josh Good

    RESPONSE 2:
    see Buck and Bär "Investigations on the biomechanical significance of
    dermatoglyphic ridges"
    in "Hands of Primates" ed. by Preuschoft and Chivers, Springer Vienna ISBN
    3-211-82385-9

    and

    Dear Mr. Ludcke,
    this is a short excerption of Buck and Bär (1993), mentioned before.
    Dermatoglyphic ridges play an (underestimated) role in static friction more
    than in slide friction in all materials tested (pine wood, glass, marble,
    and grey polyvinylechloride). This means that the frictional resistance
    perpendicular to the dermatoglyphic ridges is on average about 20% higher
    than in directions with them in static friction. Results also differ for
    different fingers. I think this might be important for the ergonomic and
    safe design of handles and surfaces and useful for your thesis. If you are
    interested in the source and facing problems you´re invited to contact me.

    Dipl.-Ing.(FH) H.F. Bär M.D.
    Orthopaedic University Clinic
    Subdepartment of Occupational Orthopaedics
    Bochum - Western Germany


    --------------------------------------------------------------------------------------------

    Justin Ludcke
    PhD Student
    School of Mechanical, Manufacturing and Medical Engineering
    Queensland University of Technology
    GPO Box 2434
    Brisbane Q 4001
    AUSTRALIA

    Ph: +61 7 3864 2980
    Mobile: +61 410 652 260
    Fax: +61 7 3864 1469
    Email : j.ludcke@qut.edu.au
    --------------------------------------------------------------------------------------------

    ---------------------------------------------------------------
    To unsubscribe send SIGNOFF BIOMCH-L to LISTSERV@nic.surfnet.nl
    For information and archives: http://isb.ri.ccf.org/biomch-l
    ---------------------------------------------------------------
Working...
X