Anyone want to do a Ph.D. in PCT-based robotics?

See http://www.sys.uea.ac.uk/studentships/ABSTRACT34.html.

Or animation:
http://www.sys.uea.ac.uk/studentships/ABSTRACT35.html
For some more detail of what I've been doing with animation, see
http://www.sys.uea.ac.uk/~jrk/visicast/RK-GW2001/.

-- Richard Kennaway, jrk@sys.uea.ac.uk, http://www.sys.uea.ac.uk/~jrk/
   School of Information Systems, Univ. of East Anglia, Norwich, U.K.

[From Bruce Nevin (01.05.03 15:05 EDT)]

Excellent!

I gather there are 12 scholarships for the 48 listed studentships (of which you offer two). Does this mean that only 12 will be filled, or that only 12 will be funded by these scholarships and others may be filled in other ways?

For those who, like me, need a reminder of what a PID controller is, there's a useful FAQ at http://www.tcnj.edu/~rgraham/PID-tuning.html

Richard, I got a 404 Not Found message for the URL
http://www.sys.uea.ac.uk/~jrk/PCT/Archy.html

         Bruce Nevin

···

At 19:30 05/03/2001 +0100, Richard Kennaway wrote:

See http://www.sys.uea.ac.uk/studentships/ABSTRACT34.html.

Or animation:
http://www.sys.uea.ac.uk/studentships/ABSTRACT35.html
For some more detail of what I've been doing with animation, see
http://www.sys.uea.ac.uk/~jrk/visicast/RK-GW2001/.

-- Richard Kennaway, jrk@sys.uea.ac.uk, http://www.sys.uea.ac.uk/~jrk/
   School of Information Systems, Univ. of East Anglia, Norwich, U.K.

[From Richard Kennaway (20010503 21:55 BST)]

Bruce Nevin (01.05.03 15:05 EDT):

Richard, I got a 404 Not Found message for the URL
http://www.sys.uea.ac.uk/~jrk/PCT/Archy.html

The current URL is http://www.sys.uea.ac.uk/~jrk/PCT/Archy/Archy.html.
I'll see if I can set up a redirection to enable the old URL to work.

-- Richard Kennaway, jrk@sys.uea.ac.uk, http://www.sys.uea.ac.uk/~jrk/
   School of Information Systems, Univ. of East Anglia, Norwich, U.K.

[From Richard Kennaway (01.05.04 12:42 BST)]

Bruce Nevin (01.05.03 15:05 EDT):

I gather there are 12 scholarships for the 48 listed studentships (of which
you offer two). Does this mean that only 12 will be filled, or that only 12
will be funded by these scholarships and others may be filled in other ways?

Anyone satisfying our research admissions criteria may be offered a place,
but possibly with no scholarship. For self-funded applicants, there may be
some limited financial help available, depending on the quality of the
individual.

Anyone wanting further details of our entry requirements and procedures
should contact Dr. Moe Razaz <mr@sys.uea.ac.uk>.

-- Richard Kennaway, jrk@sys.uea.ac.uk, http://www.sys.uea.ac.uk/~jrk/
   School of Information Systems, Univ. of East Anglia, Norwich, U.K.

[From Dag Forssell (010504 10:00 PST)]

> Richard Kennaway 3 May 2001 19:30:23 +0100
>

See http://www.sys.uea.ac.uk/studentships/ABSTRACT34.html.

Or animation:
http://www.sys.uea.ac.uk/studentships/ABSTRACT35.html
For some more detail of what I've been doing with animation, see
http://www.sys.uea.ac.uk/~jrk/visicast/RK-GW2001/.

Richard,

This is just great! Congratulations!

Best, Dag

[From Bill Powers (2001.05.04.1442 MDT)]

Richard Kennaway (20010503 21:55 BST)

The "avatar" looks great, and works pretty well on my 360 MHZ desktop. I
appreciate the problem you mention with the three-hinge approximation for a
ball-and-socket joint, but it seems to me there must be a better solution.

The shoulder-roll and shoulder-yaw torques are actually created by lateral
muscles that wrap around above and below the humerus near the shoulder. The
sum of the upper and lower muscle forces pulling from the chest creates an
inward, shoulder-yaw torque; the difference between these two forces
creates the shoulder-roll torque (about the axis of the humerus). There is
another pair of muscles pulling outward which also attach above and below
the axis of the humerus, providing the antagonist yaw and roll torques.

I believe the deltoid and its antagonists work the same way: these muscles
provide both shoulder-pitch and shoulder-roll torques. In all cases the
reaction forces work directly between the body and the humerus, not through
interacting hinges at the shoulder.

Because the vertical line of action of the deltoid swings laterally with
yaw motions at the shoulder, the force is always directly upward, parallel
to the yaw axis. The pitch torque thus always acts on the humerus at right
angles to the yaw torque, so there is never any approach to "gimbal lock"
in this joint.

Also, because the shoulder-roll torque is created by differential forces
acting at right angles to the humerus axis, the roll-torque axis is always
the same as the humerus axis, or so I think. I'm speaking only about
first-order effects.

Maybe you've already been through this and the results are incorporated in
the "signing" model. I hope to get back to our C program sometime soon and
figure out what is blowing up when the upper-arm angle nears 90 degrees.
When this problem and the gimbal-lock problem are solved, I think we can
forge ahead with Little Man 3.

Very nice work with the signing project, with a lot of practical value.

Best,

Bill P.