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RE: [RC] There must be a better way to fit a saddle ! - David LeBlancRobert Ferrand said: There are some who believe that a plaster cast or thermoplastic sheet draped over the horse's back is the solution to determining saddle fit. This creates a "mirror image" of the shape of the "Unladen" horse's back. Then everyone jumps to the conclusion that this shape must be the shape of the saddle that fits the horse's back. Not everyone, but this does give you a good starting point. However, has anyone ever provided any "objective evidence" that this is true? More importantly, has someone actually measured this concept and discovered that it is not true? Well, we couldn't use a SaddleTech guage to measure this either. It has exactly the same problem as the Equimeasure kit, except that the Equimeasure kit is actually able to pick up more information because it isn't limited to only a few points. I happen to have a Master's degree in Aerospace Engineering with a certificate in Bio-Engineering. It's a fundamentally obvious principle of structural mechanics that when you put a load on something, animal or not, it will deform and the shape will change. It's simple laws of physics. Further, we cannot treat the horse's back as a static structure. Unless the horse is standing still and not breathing, the shape will change as the horse moves, and this all depends on the animal's natural gait, which gait it has chosen, the footing, the slope of the ground, and the loading from the rider will be a function of not just the rider's weight, but their ability as well. We're talking about an extremely complex dynamic system. This also changes as both the horse and rider fatigue. To the best of my knowledge, no one has ever done the research needed to understand more than the raw basics. No static measurement system is able to even roughly approximate all of these factors. It simply cannot be done. You can't solve a dynamic structural problem with static measurements. Maybe the saddle fitting problem is that we have never had any saddle measurement instruments accurate enough to detect this error. Interesting that you bring up accuracy. The SaddleTech system attempts to compensate for the rider's weight by adjusting the measurements. The problem here is that the magnitude of the adjustments is _less_ than the accuracy of the measurement. This means the adjustment system is not actually accomplishing anything. If my measurement is +/- 5 degrees, and my adjustment is 2 degrees, the adjustment is not significant. I have a joke about how you can tell a mathematician from an engineer. Ask what is 1 plus 1,000,000? The mathematician will tell you it is 1,000,001. The engineer will reply that since we only know 1,000,000 to +/- 1000 or so, we still have about a million. While some consider a piece of baling wire or plaster cast or plastic sheet to be a form of measurement, the truth is: measurement requires a "UNIT OF MEASURE". Actually, this isn't completely true. We may only want to test whether one shape is like another. We might realistically recognize the limits of our knowledge about this extremely complex, dynamic bio-mechanical system, and understand that the best we can do with current technology is to get a good starting point. If the saddle bridges without load, or pinches the withers without load, it sure isn't going to work under load. You don't need one day of college or any fancy gizmos to figure this part out. If you are trying to determine the shape of saddle that will create even pressure on the horse's back, maybe it would be a good idea to actually meassure that pressure under the saddle, rather than guessing. Putting a pressure guage under a saddle is indeed a great start. The problem here is that we have a dynamic load, and until you can get a very high capture rate and telemetry on that device, the data you capture is NOT going to solve the problem. This is why the pressure guage predicted that one of our saddles would work well on one of our horses, but the saddle did not actually work well under real conditions. Great start, but the tool has limits. The loads could be drastically different at a trot/canter/uphill/downhill and so on. Interestingly, the Equimeasure kit did show that the saddle wasn't a good fit for that horse. Once we could place the mold into the saddle and explore, it was intuitively obvious that there was a problem, wheras spending a fair bit of money for a consultant with a gizmo pointed us in the wrong direction. Admittedly, it was a one rat study, but it was my horse and my wallet. Both the SaddleTech and Equimeasure systems have significant limitations, but the Equimeasure has been more useful to me because it is less expensive, doesn't require me to schedule an appointment with someone, and it is better able to capture the extremely complex geometry of a horse's unloaded back. The Equimeasure kit is also more portable - I can take it to the saddle instead of having to take the saddle to the consultant to check fit. The pressure guage sheet is very interesting and has a lot of potential. Unfortunately, I don't consider it to be of much practical use in the field. =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Ridecamp is a service of Endurance Net, http://www.endurance.net. Information, Policy, Disclaimer: http://www.endurance.net/Ridecamp Subscribe/Unsubscribe http://www.endurance.net/ridecamp/logon.asp Ride Long and Ride Safe!! =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
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