cortex: org/movement.org comparison

comparison org/movement.org @ 304:2dfebf71053c

Merged Winston cover letter

author	Dylan Holmes <ocsenave@gmail.com>
date	Sat, 18 Feb 2012 02:07:40 -0600
parents	1eed471e2ebf
children	7e7f8d6d9ec5

comparison

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-:35d9e7d04d87
+:2dfebf71053c
 Surprisingly enough, terristerial creatures only move by using torque
 applied about their joints.  There's not a single straight line of
 force in the human body at all!  (A straight line of force would
 correspond to some sort of jet or rocket propulsion.)
-*(next paragraph is from memory and needs to be checked!)*
+In humans, muscles are composed of muscle fibers which can contract to
+exert force. The muscle fibers which compose a muscle are partitioned
-In humans, muscles are composed of millions of sarcomeres, which can
+into discrete groups which are each controlled by a single alpha motor
-contract to exert force. A single motor neuron might control 100-1,000
+neuton. A single alpha motor neuron might control as little as three
-sarcomeres. When the motor neuron is engaged by the brain, it
+or as many as one thousand muscle fibers. When the alpha motor neuron
-activates all of the sarcomeres to which it is attached. Some motor
+is engaged by the spinal cord, it activates all of the muscle fibers
-neurons command many sarcomeres, and some command only a few. The
+to which it is attached. The spinal cord generally engages the alpha
-spinal cord generally engages the motor neurons which control few
+motor neurons which control few muscle fibers before the motor neurons
-sarcomeres before the motor neurons which control many sarcomeres.
+which control many muscle fibers.  This recruitment stragety allows
-This recruitment stragety allows for percise movements at low
+for percise movements at low strength. The collection of all motor
-strength. The collection of all motor neurons that control a muscle is
+neurons that control a muscle is called the motor pool. The brain
-called the motor pool. The brain essentially says "activate 30% of the
+essentially says "activate 30% of the motor pool" and the spinal cord
-motor pool" and the spinal cord recruits motor neurons untill 30% are
+recruits motor neurons untill 30% are activated. Since the
-activated. Since the distribution of power among motor neurons is
+distribution of power among motor neurons is unequal and recruitment
-unequal and recruitment goes from weakest to strongest, the first 30%
+goes from weakest to strongest, the first 30% of the motor pool might
-of the motor pool might be 5% of the strength of the muscle.
+be 5% of the strength of the muscle.
 My simulated muscles follow a similiar design: Each muscle is defined
 by a 1-D array of numbers (the "motor pool"). Each entry in the array
-represents a motor neuron which controlls a number of sarcomeres equal
+represents a motor neuron which controlls a number of muscle fibers
-to the value of the entry. A muscle also has a scalar :strength factor
+equal to the value of the entry. Each muscle has a scalar strength
-which determines the total force the muscle can exert when all motor
+factor which determines the total force the muscle can exert when all
-neurons are activated.  The effector function for a muscle takes a
+motor neurons are activated.  The effector function for a muscle takes
-number to index into the motor pool, and that number "activates" all
+a number to index into the motor pool, and then "activates" all the
-the motor neurons whose index is lower or equal to the number.  Each
+motor neurons whose index is lower or equal to the number.  Each
 motor-neuron will apply force in proportion to its value in the array.
 Lower values cause less force.  The lower values can be put at the
 "beginning" of the 1-D array to simulate the layout of actual human
 muscles, which are capable of more percise movements when exerting
 less force. Or, the motor pool can simulate more exoitic recruitment
 (.mult (.getWorldRotation muscle) Vector3f/UNIT_Y)
 strength (muscle-strength muscle)
 pool (motor-pool muscle)
 pool-integral (reductions + pool)
-force-index
+forces
 (vec (map  #(float (* strength (/ % (last pool-integral))))
 pool-integral))
 control (.getControl target RigidBodyControl)]
+(println-repl (.getName target) axis)
 (fn [n]
 (let [pool-index (max 0 (min n (dec (count pool))))
-force (force-index pool-index)]
+force (forces pool-index)]
 (.applyTorque control (.mult axis force))
 (float (/ force strength))))))
 (defn movement!
 "Endow the creature with the power of movement. Returns a sequence
 (view-sense movement-display-kernel))
 #+end_src
 * Adding Touch to the Worm
-#+begin_src clojure
+To the worm, I add two new nodes which describe a single muscle.
-(defn test-movement
-([] (test-movement false))
+#+attr_html: width=755
+#+caption: The node highlighted in orange is the parent node of all muscles in the worm.  The arrow highlighted in yellow represents the creature's single muscle, which moves the top segment.  The other nodes which are not highlighted are joints, eyes, and ears.
+[[../images/worm-with-muscle.png]]
+#+name: test-movement
+#+begin_src clojure
+(defn test-worm-movement
+([] (test-worm-movement false))
 ([record?]
 (let [creature (doto (worm) (body!))
 muscle-exertion (atom 0)
 muscles (movement! creature)
 (set-gravity world (Vector3f. 0 0 0))
 (.setLocation (.getCamera world)
 (Vector3f. -4.912815, 2.004171, 0.15710819))
 (.setRotation (.getCamera world)
 (Quaternion. 0.13828252, 0.65516764,
--0.12370994, 0.7323449))
+-0.12370994, 0.7323449)))
-(comment
-(com.aurellem.capture.Capture/captureVideo
-world (file-str "/home/r/proj/ai-videos/hand"))))
 (fn [world tpf]
 (muscle-display
 (map #(% @muscle-exertion) muscles)
 (if record?
 (File. "/home/r/proj/cortex/render/worm-muscles/muscles"))))))))
 the power output of the muscle . Each jump causes 20 more motor neurons to
 be recruited.  Notice that the power output increases non-linearly
 with motror neuron recruitement, similiar to a human muscle.</p>
 </div>
 #+end_html
 ** Making the Worm Muscles Video
 #+name: magick7
 #+begin_src clojure
 (ns cortex.video.magick7
 (:use cortex.test.body)
 (:use clojure.contrib.def)
 (:import java.io.File)
 (:import java.awt.image.BufferedImage)
 (:import com.jme3.scene.Node)
-(:import com.jme3.math.Vector3f)
+(:import (com.jme3.math Quaternion Vector3f))
 (:import (com.aurellem.capture Capture RatchetTimer))
 (:import com.jme3.bullet.control.RigidBodyControl))
-(cortex.import/mega-import-jme3)
 #+end_src
 * Source Listing
 - [[../src/cortex/movement.clj][cortex.movement]]
 - [[../src/cortex/test/movement.clj][cortex.test.movement]]

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comparison org/movement.org @ 304:2dfebf71053c