Fall 2023 I i experimented with retaining the three meter marks I used during week two, adding only a 1.5 meter mark. This worked well fall 2023, with the note that I held off all accelerative push unless the 3 meter mark, and then accelerated into 12 meters. If anything, a more minimal acceleration appears to be beneficial to generating a parabola.
As I did last fall, I inserted a 1.5 meter mark. On the first run I forgot to hit the lap timer - a practice run is recommended. I again refrained from making an accelerative push until the three meter mark. Just the wobbling required to remain on the board increased my velocity.
Although I intended to end at 12 meters, rainy conditions - despite the El Niño - reduced my traction on the board. I had even used a towel to improve my traction, but my Hoka Challenger 7 GTX still lacked grip on the board deck. So my acceleration was rather tentative and timid. As a result I accelerated out to 15 meters. While the tentative acceleration helped today, last fall the Challenger 7 shoes (pre-GTX version) lacked the grip I needed for maximal acceleration on Wednesday.
Above is an image of some of the gear required, minus a split timer.
The resulting data. Note that d₁~½a₁t₁² did not fit as well as hoped. The issue is that I really do not come off of the starting pole at zero meters per second.
The data in a table. I first showed that d₁~v₁t₁ does not fit the data, either visually or behaviorally. Then I added a square to t₁ as in d₁~v₁t₁² and the result suddenly fit the data better.
The above graph also depicts the exponential equation d₁~p₁e^(q₁t₁)+r₁ to demonstrate that there are two possible mathematical models that both fit the data. The exponential fits better with an R² of 1.0000.
Because d₁~½a₁t₁² still did not well fit the data, I went ahead and added in the remaining terms. v₀ confirms my long held suspicion that speeds under 0.5 m/s are unsustainable - too unstable. Thus when I push off the post I essentially jump up to 0.38 m/s very quickly, then my acceleration drops to the swizzle driven acceleration.
The three meter distances and stalling acceleration into the first three meter mark works well enough. Flattening the curve down near t=0 seconds remains a challenge.
Comments
Post a Comment