A platform rides up and down the frame side leg guide channels in response to the raising and lowering of the lower arms such that {HEAD ~ a one foot rise} in {TAIL ~ the platform} results in a three foot rise in the platform relative to ground levcel 
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A platform rides up and down the frame side leg guide channels in response to the raising and lowering of the lower arms such that { HEAD ~ a one foot rise } in { TAIL ~ the platform } results in a three foot rise in the platform relative to ground levcel
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH