cortex: org/movement.org comparison

comparison org/movement.org @ 266:bee5145ce463

Merged Robert's proprioception with Dylan's vision.

author	Dylan Holmes <ocsenave@gmail.com>
date	Mon, 13 Feb 2012 21:53:54 -0600
parents	2fdcbe8185b1
children	d487348c461c

comparison

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-:e57d8c52f12f
+:bee5145ce463
-#+title: Movement!
+#+title: Simulated Muscles
 #+author: Robert McIntyre
 #+email: rlm@mit.edu
 #+description: muscles for a simulated creature
 #+keywords: simulation, jMonkeyEngine3, clojure
 #+SETUPFILE: ../../aurellem/org/setup.org
 #+INCLUDE: ../../aurellem/org/level-0.org
+* Muscles
 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 propulseion.)
+correspond to some sort of jet or rocket propulsion.)
+*(next paragraph is from memory and needs to be checked!)*
-Here's how motor-control/ proprioception will work: Each muscle is
-defined by a 1-D array of numbers (the "motor pool") each of which
+In humans, muscles are composed of millions of sarcomeres, which can
-represent muscle fibers. A muscle also has a scalar :strength factor
+contract to exert force. A single motor neuron might control 100-1,000
-which determines how strong the muscle as a whole is.  The effector
+sarcomeres. When the motor neuron is engaged by the brain, it
-function for a muscle takes a number < (count motor-pool) and that
+activates all of the sarcomeres to which it is attached. Some motor
-number is said to "activate" all the muscle fibers whose index is
+neurons command many sarcomeres, and some command only a few. The
-lower than the number.  Each fiber will apply force in proportion to
+spinal cord generally engages the motor neurons which control few
-its value in the array.  Lower values cause less force.  The lower
+sarcomeres before the motor neurons which control many sarcomeres.
-values can be put at the "beginning" of the 1-D array to simulate the
+This recruitment stragety allows for percise movements at low
-layout of actual human muscles, which are capable of more percise
+strength. The collection of all motor neurons that control a muscle is
-movements when exerting less force.
+called the motor pool. The brain essentially says "activate 30% of the
+motor pool" and the spinal cord recruits motor neurons untill 30% are
-#+name: movement
+activated. Since the distribution of power among motor neurons is
+unequal and recruitment goes from weakest to strongest, 30% of the
+motor pool might 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 number represents a
+motor neuron which controlls a number of sarcomeres equal to the
+number. A muscle also has a scalar :strength factor which determines
+the total force the muscle can exert when all motor neurons are
+activated.  The effector function for a muscle takes a number to index
+into the motor pool, and that number "activates" all the 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 strageties which
+do not correspond to human muscles.
+This 1D array is defined in an image file for ease of
+creation/visualization. Here is an example muscle profile image.
+#+caption: A muscle profile image that describes the strengths of each motor neuron in a muscle. White is weakest and dark red is strongest. This particular pattern has weaker motor neurons at the beginning, just like human muscle.
+[[../images/basic-muscle.png]]
+* Blender Meta-data
+In blender, each muscle is an empty node whose top level parent is
+named "muscles", just like eyes, ears, and joints.
+These functions define the expected meta-data for a muscle node.
+#+name: muscle-meta-data
 #+begin_src clojure
-(ns cortex.movement
+(in-ns 'cortex.movement)
-"Give simulated creatures defined in special blender files the power
-to move around in a simulated environment."
-{:author "Robert McIntyre"}
-(:use (cortex world util sense body))
-(:use clojure.contrib.def)
-(:import java.awt.image.BufferedImage)
-(:import com.jme3.scene.Node)
-(:import com.jme3.math.Vector3f)
-(:import com.jme3.bullet.control.RigidBodyControl))
-(defn muscle-profile
-"Return a vector where each entry is the strength of the \"motor
-pool\" at that part in the muscle."
-[#^BufferedImage profile]
-(vec
-(let [width (.getWidth profile)]
-(for [x (range width)]
-(- 255
-(bit-and
-0x0000FF
-(.getRGB profile x 0)))))))
 (defvar
 ^{:arglists '([creature])}
 muscles
 (sense-nodes "muscles")
 "Return the children of the creature's \"muscles\" node.")
-(defn movement-fn
+(defn muscle-profile-image
+"Get the muscle-profile image from the node's blender meta-data."
+[#^Node muscle]
+(if-let [image (meta-data muscle "muscle")]
+(load-image image)))
+(defn muscle-strength
+"Return the strength of this muscle, or 1 if it is not defined."
+[#^Node muscle]
+(if-let [strength (meta-data muscle "strength")]
+strength 1))
+(defn motor-pool
+"Return a vector where each entry is the strength of the \"motor
+neuron\" at that part in the muscle."
+[#^Node muscle]
+(let [profile (muscle-profile-image muscle)]
+(vec
+(let [width (.getWidth profile)]
+(for [x (range width)]
+(- 255
+(bit-and
+0x0000FF
+(.getRGB profile x 0))))))))
+#+end_src
+Of note here is =(motor-pool)= which interprets the muscle-profile
+image in a way that allows me to use gradients between white and red,
+instead of shades of gray as I've been using for all the other
+senses. This is purely an aesthetic touch.
+* Creating Muscles
+#+name: muscle-kernel
+#+begin_src clojure
+(in-ns 'cortex.movement)
+(defn movement-kernel
 "Returns a function which when called with a integer value inside a
 running simulation will cause movement in the creature according
 to the muscle's position and strength profile. Each function
 returns the amount of force applied / max force."
-[#^Node parts #^Node muscle]
+[#^Node creature #^Node muscle]
-(let [target (closest-node parts muscle)
+(let [target (closest-node creature muscle)
 axis
 (.mult (.getWorldRotation muscle) Vector3f/UNIT_Y)
-strength (meta-data muscle "strength")
+strength (muscle-strength muscle)
-image-name (read-string (meta-data muscle "muscle"))
-image (load-image image-name)
+pool (motor-pool muscle)
-fibers (muscle-profile image)
+pool-integral (reductions + pool)
-fiber-integral (reductions + fibers)
 force-index
-(vec (map  #(float (* strength (/ % (last fiber-integral))))
+(vec (map  #(float (* strength (/ % (last pool-integral))))
-fiber-integral))
+pool-integral))
 control (.getControl target RigidBodyControl)]
 (fn [n]
-(let [pool-index (max 0 (min n (dec (count fibers))))
+(let [pool-index (max 0 (min n (dec (count pool))))
 force (force-index pool-index)]
 (.applyTorque control (.mult axis force))
 (float (/ force strength))))))
 (defn movement!
 "Endow the creature with the power of movement. Returns a sequence
 of functions, each of which accept an integer value and will
 activate their corresponding muscle."
 [#^Node creature]
 (for [muscle (muscles creature)]
-(movement-fn creature muscle)))
+(movement-kernel creature muscle)))
+#+end_src
+=(movement-kernel)= creates a function that will move the nearest
+physical object to the muscle node. The muscle exerts a rotational
+force dependant on it's orientation to the object in the blender
+file. The function returned by =(movement-kernel)= is also a sense
+function: it returns the percent of the total muscle strength that is
+currently being employed. This is analogous to muscle tension in
+humans and completes the sense of proprioception begun in the last
+post.
+* Visualizing Muscle Tension
+Muscle exertion is a percent of a total, so the visulazation is just a
+simple percent bar.
+#+name: visualization
+#+begin_src clojure
 (defn movement-display-kernel
 "Display muscle exertion data as a bar filling up with red."
 [exertion]
 (let [height 20
 width 300
 (defn view-movement
 "Creates a function which accepts a list of muscle-exertion data and
 displays each element of the list to the screen."
 []
 (view-sense movement-display-kernel))
+#+end_src
-#+end_src
+* Adding Touch to the Worm
+#+begin_src clojure
+(defn test-movement
+([] (test-movement false))
+([record?]
+(let [creature (doto (worm) (body!))
+muscle-exertion (atom 0)
+muscles (movement! creature)
+muscle-display (view-movement)]
+(.setMass
+(.getControl (.getChild creature "worm-11") RigidBodyControl)
+(float 0))
+(world
+(nodify [creature (floor)])
+(merge standard-debug-controls
+{"key-h"
+(fn [_ value]
+(if value
+(swap!  muscle-exertion (partial + 20))))
+"key-n"
+(fn [_ value]
+(if value
+(swap! muscle-exertion (fn [v] (- v 20)))))})
+(fn [world]
+(if record?
+(Capture/captureVideo
+world
+(File. "/home/r/proj/cortex/render/worm-muscles/main-view")))
+(light-up-everything world)
+(enable-debug world)
+(.setTimer world (RatchetTimer. 60))
+(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))
+(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"))))))))
+#+end_src
+* Video Demonstration
+#+begin_html
+<div class="figure">
+<center>
+<video controls="controls" width="550">
+<source src="../video/worm-muscles.ogg" type="video/ogg"
+	  preload="none" poster="../images/aurellem-1280x480.png" />
+</video>
+</center>
+<p>The worm is now able to move. The bar in the lower right displays
+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
+(:import java.io.File)
+(:use clojure.contrib.shell-out))
+(defn images [path]
+(sort (rest (file-seq (File. path)))))
+(def base "/home/r/proj/cortex/render/worm-muscles/")
+(defn pics [file]
+(images (str base file)))
+(defn combine-images []
+(let [main-view (pics "main-view")
+muscles (pics "muscles/0")
+targets (map
+#(File. (str base "out/" (format "%07d.png" %)))
+(range 0 (count main-view)))]
+(dorun
+(pmap
+(comp
+(fn [[ main-view muscles target]]
+(println target)
+(sh "convert"
+main-view
+muscles "-geometry" "+320+440" "-composite"
+target))
+(fn [& args] (map #(.getCanonicalPath %) args)))
+main-view muscles targets))))
+#+end_src
+#+begin_src sh :results silent
+cd ~/proj/cortex/render/worm-muscles
+ffmpeg -r 60 -i out/%07d.png -b:v 9000k -c:v libtheora worm-muscles.ogg
+#+end_src
+* Headers
+#+name: muscle-header
+#+begin_src clojure
+(ns cortex.movement
+"Give simulated creatures defined in special blender files the power
+to move around in a simulated environment."
+{:author "Robert McIntyre"}
+(:use (cortex world util sense body))
+(:use clojure.contrib.def)
+(:import java.awt.image.BufferedImage)
+(:import com.jme3.scene.Node)
+(:import com.jme3.math.Vector3f)
+(:import com.jme3.bullet.control.RigidBodyControl))
+#+end_src
+#+name: test-header
+#+begin_src clojure
+(ns cortex.test.movement
+(:use (cortex world util sense body movement))
+(: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.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]]
+- [[../src/cortex/video/magick7.clj][cortex.video.magick7]]
+#+html: <ul> <li> <a href="../org/movement.org">This org file</a> </li> </ul>
+- [[http://hg.bortreb.com ][source-repository]]
 * COMMENT code generation
 #+begin_src clojure :tangle ../src/cortex/movement.clj
-<<movement>>
+<<muscle-header>>
-#+end_src
+<<muscle-meta-data>>
+<<muscle-kernel>>
+<<visualization>>
+#+end_src
+#+begin_src clojure :tangle ../src/cortex/test/movement.clj
+<<test-header>>
+<<test-movement>>
+#+end_src
+#+begin_src clojure :tangle ../src/cortex/video/magick7.clj
+<<magick7>>
+#+end_src

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comparison org/movement.org @ 266:bee5145ce463