The full abstract from ISSS-Japan (2005) is published through a medium that's associated with Univ. Vermont, College of Medicine, Dept of Orthopaedics & Rehabilitation, Prof. Robert J. Johnson, MD. It is copyrighted — therefore, Dr. Johnson must supply it to you: He can be reached at UVM College of Medicine, Dept of Ortho ... in Burlington, Vt.
Here is data from one of several 'ordinary' bindings that I (personally) tested at the same time in 2005 re my public presentation ISSS-Japan. This data clearly shows what's going-on when the abduction force (applied to the medial edge of the ski) is the resultant (superpositioned) vector of the sum of the incremental-forces interacting (laterally) between the snow surface and the ski when neither the tip or the tail of a ski (shaped or not) 'slides-out' (when neither end of the ski slides-out). Remember, utilizing Isaac Newton's fundamental laws of action and reaction — a 'laterally-trapped' ski (at peak loading) is 'equal (in magnitude) and opposite (in direction)' of the skier's CG moving laterally (relative to the laterally-trapped ski) when the hip is locked at maximum IR (internal rotation).
Ordinary binding: Valgus and tibial torque response (absolute-values w/o polarity) to applied abduction forces.
(each dot is an individual test: the lines are added to show 'association').
Here we see that when an abduction force is applied near the center of the ski, valgus torque is maximal while tibia torque is minimal.
The elastic limit of a 50th percentile male's ACL = 25 daNm of valgus torque.
All 'ordinary' bindings 'feel' zero tibial torque when valgus torque is maximal.
All 'ordinary' bindings 'react to' ONLY tibial torque: Ordinary bindings do not respond to valgus torque (they have no clues about valgus torque when the applied abduction force is applied under (or near) the projected axis of the tibia.
As presented at ISSS-Japan (2005), a binding with lateral heel release (a Geze SE3 toe mounted at the heel — not shown, here) limits valgus torque, depending upon the setting.
During 'valgus collapse' — when a BIAD (boot induced anterior drawer) pre-load (rear-weighting) is combined with abduction loading (as depicted in the test apparatus in the photo of my post #175 in this thread), the data looks like this:
Peak resultant valgus-tibia release values (shown as absolute-values w/o polarity); 'ordinary' binding.
(Each polygon is an individual test.)
Values plotted: resultant valgus-tibial torque (shown as the 'bottom line' in each polygon);
Resultant valgus-tibial torque + BIAD (boot induced anterior drawer) pre-load (shown as the 'top line' in each polygon);
BIAD pre-load (a constant pre-load in each test, here) generates the difference between top and bottom lines in each polygon;
Small 'target' (see lower right corner) is the elastic limit of a 50th percentile male's ACL (25 daNm of resultant valgus-tibia torque);
'Ordinary' binding with 'DIN-setting' = ~4 daNm of tibia (only) torque (length of bottom line segment in lower left corner).
The peak resultant values that are shown in this graph stop short of 25 daNm only because my current test equipment measures up-to 23 daNm.
It's obvious where those values will go when the measuring instruments can read beyond 23 daNm (sorry — pls extrapolate on your own).
That's "release" relative to the elastic limit of the ACL, with an 'ordinary' binding.
Now, "retention" ( "anti-pre-release" ). Pls see graph, below:
Forward retention ( anti-pre-release ) as a function of release; binding brands 'A thru F'.
Pls remember, DIN ~translates to daNm of torque (depending upon boot sole length) — and is a standardized unit of release (not retention).
Retention units are presently not displayed on any given binding.
Obviously, retention ≠ release.
Binding 'A' set at DIN ~11 can withstand a 'retention situation' of ~40 Jules.
Binding 'F' set at DIN ~11 can only withstand a 'retention situation' of ~12 Jules.
Binding 'A' obviously provides far superior anti-pre-release characteristics relative to binding 'F'.
The concept can also be viewed this way:
A given 'retention situation' of ~19 Jules is withstood by binding 'A' at DIN ~7.5.
A given 'retention situation' of ~19 Jules requires binding 'F' to be set at DIN ~16.
Again, Binding 'A' obviously provides far superior anti-pre-release characteristics relative to binding 'F' (would your rather have your binding set at 16 or 7.5 to deal with the same 'retention situation' ?).
Different design-parameters produce different retention limits at any given release setting.
Some bindings are obviously designed differently from others.
Applying 'certain' design parameters to EACH MODE of release can mitigate pre-release IN EACH MODE independenly of release settings ('DIN').
( Pls take my word for that statement at this time :)
This is a new engineering concept based upon the principles of 'Axiomatic Design' (see the book, The Principles of Design, by MIT Prof. Nam Suh).
Axiomatic Design principles allow new possibilities never imagined before for alpine ski bindings.
I sincerely trust that this is the data you're looking for, jzamp & JayT :)
Additionally, (almost) everyone can visit my biomechanics lab here in Stowe, Vermont — by appointment.
A CADD model of the release-torque data (with tibia torque; valgus torque; resultant tibia-valgus torque; and applied abduction force) for 'ordinary' bindings will be available within the website [http://www.HowellSkiBindings.com], soon.
Howell™ Ski Bindings
( The 'ordinary' binding shown in the 1st & 2nd graphs in this post is a beautiful Geze 952 TC.
Geze® is a registered trademark of Geze GmbH of Stüttgart, Germany. Geze® is not Howell™.
Bindings labeled 'A' through 'F' in the 3rd graph in this post bear no alphanumeric relationship to any brand. )
Copyright © 2013 by Howell™ Ski Bindings. All rights reserved.
Edited by Richard Howell - 2/10/13 at 11:57am