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YOUR JUMPING STILTS => Problems and solutions => Topic started by: OriginalMrH on April 14, 2011, 05:05:23 PM

Title: Pressure on the hooves/ground
Post by: OriginalMrH on April 14, 2011, 05:05:23 PM
Does anyone know the pressure on the hooves or ground when you land. Or how to work it out.

I was thinking it would be slightly more than just a normal persons weight as the pressure goes into the spring.

Got kicked out of 'our gym' gym today as apparently a little bit below the floor are heating pipes and they think there might be too much pressure on them.

Wouldn't let us put mats down on the floor either to jump on instead.

Any info would be good as I can't find any.

Many Thanks
Title: Re: Pressure on the hooves/ground
Post by: billymaya on April 14, 2011, 07:19:50 PM
i have the same problem down here mate i cant find a gym any where that will let us use there halls as most of them are air sprung floors and they are worried we would damage them :( its pants
Title: Re: Pressure on the hooves/ground
Post by: Locky on April 14, 2011, 07:21:47 PM
It is a tricky situation and we might think our stilts would be ok, even with mats down but we really don't know and without some conclusive tests on some sort of pressure gauge then we'd never know.

Unfortunately all you can really do is either try and talk to them and have a better conversation with them about it or just cut your losses and move on.
Title: Re: Pressure on the hooves/ground
Post by: carlgreen on April 14, 2011, 10:53:48 PM
What gym is this in Cambridge, we tried as many as we could and nobody wanted us in there :(
Title: Re: Pressure on the hooves/ground
Post by: SNuD on April 15, 2011, 01:03:22 AM
It's very much the same the whole world over! finding a gym for bocking in and keeping it is a nightmare  :Ccry:

It shouldn't be too hard to calculate!  :Ceek:

Need a maths or physics student  :Cyes:
Title: Re: Pressure on the hooves/ground
Post by: Hilly-of-the-Marshes on April 15, 2011, 11:43:12 AM
What gym is this in Cambridge, we tried as many as we could and nobody wanted us in there :(

no carl it's in middlesbrough, it's our uni's main gym hall - said he was worried about us breaking the sprung floor
Title: Re: Pressure on the hooves/ground
Post by: carlgreen on April 15, 2011, 09:54:49 PM
ahhhh my bad :(
Title: Re: Pressure on the hooves/ground
Post by: bendover90 on April 15, 2011, 10:10:03 PM
i happen to have a accelerometer at home, ill try and work it out
Title: Re: Pressure on the hooves/ground
Post by: Hilly-of-the-Marshes on April 16, 2011, 11:20:39 AM
im actually pretty sure it's sorted now - i got a text from oli saying we've got the gym on monday (though i would still check with oli to be safe) but thanks.
Title: Re: Pressure on the hooves/ground
Post by: Mibsportler on April 16, 2011, 11:25:23 AM
heya - i was wondering if i cud come if u v a gym meet or outdoor meet this monday - i still v the next week off (hooray school) and wud be up to some bocking further away  :Claugh: as there is no one around  :Ccry:
Title: Re: Pressure on the hooves/ground
Post by: Jason on April 16, 2011, 08:52:29 PM
Ok folks a little bit of kitchen physics here

Not sure this is right but if someone can explain all the facts another  way or knows more about physics feel free to correct me as I am unskilled in this field

Now if you drop a human from 8 feet they will normally break  :Claugh: unless they manage to disipate the force somehow

Free runners absorb the shock with a mixture of muscle and rolling
Judo etc absord the shock by spreading the load over the whole body as they fall (thereby minimising the impact to any one area

The stilts do something similar by absorbing the energy and decelerating us using the spring

So working on this we are hitting the floor with a maximum force of the amount that it takes to bottom the spring

This isn't the weight the spring is rated at it is the full weight it takes to compress it

I have a machine that compresses the spring by about one third and that takes a 114 kg spring up to 130/140 kg

So working on the basis that it trebles I would say the max weight for a bocker hitting the ground would be around 300/400 kg

This is not bourn out by a simple test though

If I loaded 400 kg onto the area of a set of hoofs it would sink into my lawn a fair way

But I can bounce on my lawn to the point of bottoming out and not leave massive holes a foot deep

So if anyone wants to get an exact weight for the landing bocker I have an experiment you can conduct

Get one good heavy bocker and get him to bounce to the point of bottoming on and area of grass

Measure a quantity of the hoof marks to get an average depth that they have sunk into the lawn (this has to be a fairly large quantity to allow for the difference of local hardness of the ground)

Next bolt a pair of hoofs to the bottom of a platform that you can stand on and make sure they stand out more than the average depth you got in the last bit (use packers ect)

Now stand on said platform and check the depth of the impresion
Next add a mate on your back or fill your pockets with weights and repeat

You get the idea
When you manage to make hoofmarks the same depth as the control average weigh all the people/weights and that will be the max weight you will be putting on the gym floor

Right I don't have the time to do this so who is gonna volunteer  :Claugh:

Jason  :Hoofies2: :CGEEK:
Title: Re: Pressure on the hooves/ground
Post by: chocl8 on April 18, 2011, 12:33:06 PM
We have an impact testing lab at uni. The stuff they use for crashing cars into... Fairly sure it wouldn't be too hard turning it horizontal and bouncing on it...

However it wouldn't be fair unless i tested lots of different stilts, so I'l need to have a new pair of exo pros, a set of skips, some velocities, i suppose some poweriser '08s, some new T-rex's, and some speedjumpers. Oh and of course skyrunners.

Sorted. :)
Title: Re: Pressure on the hooves/ground
Post by: Hilly-of-the-Marshes on April 18, 2011, 03:20:23 PM
alternatively, does anybody go to a gym regularly with a sprung floor?
or maybe one that you used to go to, but didn't ban you & you mauybe only stopped going to because it was too expensive etc.
Title: Re: Pressure on the hooves/ground
Post by: Squeeker on April 18, 2011, 04:21:06 PM
Ok folks a little bit of kitchen physics here

Not sure this is right but if someone can explain all the facts another  way or knows more about physics feel free to correct me as I am unskilled in this field

Now if you drop a human from 8 feet they will normally break  :Claugh: unless they manage to disipate the force somehow

Free runners absorb the shock with a mixture of muscle and rolling
Judo etc absord the shock by spreading the load over the whole body as they fall (thereby minimising the impact to any one area

The stilts do something similar by absorbing the energy and decelerating us using the spring

So working on this we are hitting the floor with a maximum force of the amount that it takes to bottom the spring

This isn't the weight the spring is rated at it is the full weight it takes to compress it

I have a machine that compresses the spring by about one third and that takes a 114 kg spring up to 130/140 kg

So working on the basis that it trebles I would say the max weight for a bocker hitting the ground would be around 300/400 kg

This is not bourn out by a simple test though

If I loaded 400 kg onto the area of a set of hoofs it would sink into my lawn a fair way

But I can bounce on my lawn to the point of bottoming out and not leave massive holes a foot deep

So if anyone wants to get an exact weight for the landing bocker I have an experiment you can conduct

Get one good heavy bocker and get him to bounce to the point of bottoming on and area of grass

Measure a quantity of the hoof marks to get an average depth that they have sunk into the lawn (this has to be a fairly large quantity to allow for the difference of local hardness of the ground)

Next bolt a pair of hoofs to the bottom of a platform that you can stand on and make sure they stand out more than the average depth you got in the last bit (use packers ect)

Now stand on said platform and check the depth of the impresion
Next add a mate on your back or fill your pockets with weights and repeat

You get the idea
When you manage to make hoofmarks the same depth as the control average weigh all the people/weights and that will be the max weight you will be putting on the gym floor

Right I don't have the time to do this so who is gonna volunteer  :Claugh:

Jason  :Hoofies2: :CGEEK:

I'm not sure if this is what you mean or an adaption to it, but, maybe putting something of equivelent size to stilt hooves on your feet, bounce around on grass, then put stilts on do the same and measure if there is any significant difference in depth of the indents?
Title: Re: Pressure on the hooves/ground
Post by: Jason on April 18, 2011, 08:16:30 PM
Not a bad idea Squeeker

The real test that I thought of after posting this is to find a freandly weighbridge and ask to bounce on it

That would give you a weight and then all you have to do is a little maths to figure out the lb/sq"

The only problem is that the people that own/run the gym will just say they don't care and no you can't use it

You are fighting human nature and you will never win so best to just keep trying different gyms till you get someone reasonable or with and old floor they don't really care about

Jason  :Hoofies2: :CGEEK: