On 20:07 5 Aug 2020, TMS320 said:

On 05/08/2020 15:14, JNugent wrote:
On 05/08/2020 08:45, TMS320 wrote:
On 05/08/2020 01:35, JNugent wrote:
On 04/08/2020 13:47, TMS320 wrote:
On 04/08/2020 12:39, JNugent wrote:
On 04/08/2020 08:14, TMS320 wrote:
On 03/08/2020 23:51, JNugent wrote:

If the effective centre of gravity of a bicycle and its rider is
raised, eg, by placing a heavy load high up, perhaps by the
wearing of a loaded backpack, what effect does that have on its
stability? Does it:

(a) decrease stability, or

(b) increase stability, or

(c) have no effect on stability?

You're doing is the equivalent of saying that the sun rises over
one horizon and sets over another. When asked why? you then ask
"are you claiming it doesn't do this?" when the answer you should
be giving has something to do with orbit and rotation.

You claim a). Now show your working.

There we have it.

Where? There is no working.

You are insisting (with as much force as you dare for fear of
rightful ridicule) that raising a cyclist's centre of gravity will
not decrease that person's stability.

Thank you for being as clear as you feel able. It'll do. Your
meaning is plain enough.

Oh, it's certainly clear enough that you don't have a clue.

You are insisting that raising the centre of gravity does not affect
stability.

Thanks for making your (erroneous) position clear.

I recall that on a legal forum you once related how you started your
working career failing to be an electrical technician. You should know
there is more to science than stripping wires.

Thank you for making the desperation of your position - insisting that
a raised centre of gravity will not affect the balance of a bicycle -
even clearer.

(That confirms I'm not thinking of the wrong person.)

Your position was that raised CoG decreases stability. Now it "affects
stability".

It's an inverted pendulum problem. An inverted pendulum is inherently
unstable and the thing that keeps it upright is a servo mechanism. Turn
the servo mechanism off and it will fall over. CoG and moment of inertia
are just parameters that have to be accounted for the servo. Thus when
masses are added or relocated on a bike or on the person riding it, it
might take a moment to recalibrate but the fundamentals don't change. A
human can do the calibration once and remember it for next time.

A nice example is a space rocket. This is balanced on one point, not two
as a bike (try standing on one leg with your eyes closed). When a rocket
takes off, the fuel load reduces so the GoG and MoI are constantly
changing accordingly. It's not a question that the rocket becomes more
or less stable, it's all down to whether the servo mechanism is good
enough to keep it pointing up.

In other words, a shifting rucksack packed with groceries will destabilise
a cyclist. If it is more than he can compensate for then he will fall
off. Q.E.D.