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On Sat, May 31, 2014 at 3:14 AM, Dag Forssell csgarchive@pctresources.com wrote:
[From Dag Forssell 2014 0530 18:20 PDT]
Adam, Bruce, Rupert, others,
I have reviewed the video of Bill’s presentation of this paper in 1993.
It does not appear to go past fig 4.
I think I have correctly identified fig 5 in the attached pdf.
Fig 6 (page 11) should be a rather standard two-level system for the
three axis of control.
Can you guys help me by pointing to a suitable example of this in our
extensive literature, or draw one for me to copy.
Could figure 5 be more appropriately this figure?
[From Bill Powers (920312.1000)]
The kinesthetic control systems in this model are taken directly from the
basic known circuitry of the tendon and stretch reflexes. Schematically:
Alpha efferent
Gamma efferent (voluntary reference
(length reference signal)
signal) |
| | (Spinal
| (stretch | Motor
V error sig) + | Neuron)
Mechanical + V /
Comparator — Kg ---------->Comparator------------
^ ^ ----> - |
| | | (force signal) | (contraction
| | | | sensitivity)
| (sensitivity)->--Kt-- (spring Ko
| | constant) |
| |force Ks V MUSCLE
| anchor |||--O------- //////////////////--LOAD
| receptor --||||||||
| | stretch
| (mechanical effects) | receptor
---------------<--------------------
This diagram really represents two control systems using opposing muscles
and balanced (push-pull) pairs of reference signals. I have reduced the
pair to a single system to make the model simpler. As a result, the
“muscle” can both push and pull on the load, and all signals can be both
positive and negative. Load position is an angular measure.
There are two loops in this system: the force loop involving the Golgi
tendon organs and the stretch loop involving the muscle spindle containing
the annulospiral stretch receptors.
[/end quote]
Could fig 6 be something like figure 15 from Bill’s Byte Article Part 3, page 10?
Adam