I took jumping stilts classes in 2010-11. They work the same way -- you swing arms and body in the air, *land with straight knees* to compress the spring and preserve the energy, and then fly back up in the air. Maybe they are less efficient than the proposed device, but...
Running in them, even properly like mentioned, was like running a sprint. You were wet and exhausted in half a minute.
Fell from them twice -- once while running, a rubber shoe of the leg that was moving forward, brushed the asphalt, and I fell forward. Despite my arms were ahead, I hit the asphalt with elbows and ribs.
The other time, year later, a rubber shoe broke apart when I landed on it, and the other leg, under much weight, bended slightly off the turning plane -- there was no fracture, but I barely could walk or cycle. It took a week till I could cycle, 2-3 weeks to walk normally and 3-4 months to stop feeling pain.
Overall, it's too exhausting, you can't run in low energy mode. Walking in them is noteably harder and not much faster. You also can't stand straight in them -- must always keep stepping to keep balance, because there are no human feet to balance back&forth.
Another issue is that it puts a lot of load on spinal disks, and some bone/connective tissue conditions forbid this -- you can walk but jumping will cause chronic pain for some time.
Not to mention you can't walk in them in autumn, when asphalt is wet and covered with slippery leaves.
Overall, it's more like downhill MTB -- for skilled and fit, and not scared of a fracture every season.
==== EDIT: Ok, maybe the whole problem with jumping stilts is height. I'd still love to see a mechanical stilts with springs that don't put you that high in the air, but have springs on the sides.
Running in them, even properly like mentioned, was like running a sprint. You were wet and exhausted in half a minute.
Fell from them twice -- once while running, a rubber shoe of the leg that was moving forward, brushed the asphalt, and I fell forward. Despite my arms were ahead, I hit the asphalt with elbows and ribs.
The other time, year later, a rubber shoe broke apart when I landed on it, and the other leg, under much weight, bended slightly off the turning plane -- there was no fracture, but I barely could walk or cycle. It took a week till I could cycle, 2-3 weeks to walk normally and 3-4 months to stop feeling pain.
Overall, it's too exhausting, you can't run in low energy mode. Walking in them is noteably harder and not much faster. You also can't stand straight in them -- must always keep stepping to keep balance, because there are no human feet to balance back&forth.
Another issue is that it puts a lot of load on spinal disks, and some bone/connective tissue conditions forbid this -- you can walk but jumping will cause chronic pain for some time.
Not to mention you can't walk in them in autumn, when asphalt is wet and covered with slippery leaves.
Overall, it's more like downhill MTB -- for skilled and fit, and not scared of a fracture every season.
==== EDIT: Ok, maybe the whole problem with jumping stilts is height. I'd still love to see a mechanical stilts with springs that don't put you that high in the air, but have springs on the sides.