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| − | = NXT-Python Documentation = | + | = CS282 - Robotics = |
| − | Largely a work in-progress, please add/edit as you learn the details. Note that this page is documenting the NXT-Python v1.1 release (http://code.google.com/p/nxt-python/), not the NXT_Python v0.7 release which appears to have gone dormant (note hyphen vs underscore).
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| − | === nxt.locator === | + | === Software Stack === |
| − | The function of this module is to locate NXT brick(s). Returns an <code>nxt.bluesock.BlueSock</code> object for robots connected by Bluetooth and a <code>nxt.usbsock.USBSock</code> object for robot connected by USB, and throws <code>nxt.locator.BrickNotFoundError</code> if none can be found.
| + | * Notes here |
| | | | |
| − | * Status: incomplete as of 2010-02-14
| + | === Python === |
| − | | + | * [[nxt-python-doc|NXT-Python Documentation |
| − | * Objects
| + | * [[nxt-python-threads|Thread Notes |
| − | ** <code>nxt.bluesock.BlueSock</code> - The object returned by <code>find_one_brick()</code> when a brick is found on a Bluetooth connection [defined in nxt.bluesock]
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| − | ** <code>nxt.usbsock.USBSock</code> - The object returned by <code>find_one_brick()</code>when a brick is found on a USB connection [defined in nxt.usbsock]
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| − | ** <code>nxt.brick.Brick</code> - The object returned by the <code>connect()</code> method [defined in nxt.brick]
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| − | | |
| − | * Methods
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| − | ** <code>connect()</code> - Try to connect to the brick.
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| − | ** <code>close()</code> - Close connection to brick.
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| − | ** <code>host</code> - Returns the address of the brick (if connected via Bluetooth connection)
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| − | ** generator object <code>find_bricks()</code>
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| − | *** <code>next()</code> - Find the next brick in the sequence, returns the same thing as <code>find_one_brick()</code>.
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| − | ** <code>find_one_brick()</code>
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| − | ** <code>find_bricks(host=None, name=None)</code> - Find all the bricks in the area, returns a generator object <code>find_bricks</code>.
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| − | | |
| − | * Example
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| − | import nxt.locator
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| − | sock = nxt.locator.find_one_brick()
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| − | brick = sock.connect()
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| − | if hasattr(brick, 'host'):
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| − | print brick.host
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| − | else:
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| − | print "brick.host is not defined for USB connections"
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| − | sock.close()
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| − | | |
| − | === nxt.motor ===
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| − | | |
| − | * Port Constants
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| − | ** <code>PORT_A</code>
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| − | ** <code>PORT_B</code>
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| − | ** <code>PORT_C</code>
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| − | ** <code>PORT_ALL</code>
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| − | | |
| − | * Mode Constants
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| − | ** <code>MODE_IDLE</code>
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| − | ** <code>MODE_MOTOR_ON</code>
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| − | ** <code>MODE_BRAKE</code>
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| − | ** <code>MODE_REGULATED</code>
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| − | | |
| − | * Regulation Constants
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| − | ** <code>REGULATION_IDLE</code>
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| − | ** <code>REGULATION_MOTOR_SPEED</code>
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| − | ** <code>REGULATION_MOTOR_SYNC</code>
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| − | | |
| − | * Run State Constants
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| − | ** <code>RUN_STATE_IDLE</code>
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| − | ** <code>RUN_STATE_RAMP_UP</code>
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| − | ** <code>RUN_STATE_RUNNING</code>
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| − | ** <code>RUN_STATE_RAMP_DOWN</code>
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| − | | |
| − | * Objects
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| − | ** <code>nxt.motor.Motor</code> - The object returned by <code>Motor(brick, port)</code>
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| − | ** Class Methods
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| − | ***_debug_out(self, message)
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| − | *** set_output_state(self)
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| − | *** get_output_state(self)
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| − | *** reset_position(self, relative)
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| − | *** run(self, power=100, regulated=1)
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| − | *** stop(self, braking=1)
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| − | *** update(self, power, tacho_limit, braking=False, max_retries=-1)
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| − | | |
| − | * Methods | |
| − | | |
| − | * Example
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| − | | |
| − | import nxt.locator
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| − | import nxt.motor
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| − | from time import sleep
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| − | sock = nxt.locator.find_one_brick()
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| − | brick = sock.connect()
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| − | motor_a = nxt.motor.Motor(brick, nxt.motor.PORT_A)
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| − | print "Initial Position:", motor_a.get_output_state()[7]
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| − | motor_a.update( 127, 360, True ) # Turn 360 degrees at full power and brake
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| − | motor_a.update( -127, 360 ) # Turn -360 degrees at full power and coast
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| − | sleep( 3 ) # update is non-blocking when braking is false, must wait for finish
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| − | print "Final Position:", motor_a.get_output_state()[7]
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| − | sock.close()
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| − | | |
| − | === nxt.sensor ===
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| − | | |
| − | * Status: incomplete as of 2010-02-14
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| − | | |
| − | * Objects
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| − | | |
| − | * Methods
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| − | | |
| − | * Example
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| − | | |
| − | === nxt.compass ===
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| − | | |
| − | * Status: incomplete as of 2010-02-14
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| − | | |
| − | * Objects
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| − | **CompassSensor
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| − | | |
| − | * Methods
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| − | **CompassSensor(bot,port)
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| − | **get_sample() returns a value between zero and 180 depending on the heading of the sensor. There is a one-to-two ratio between degrees from due North and get_sample() values. At the moment this generally returns an error.
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| − | **Methods to add
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| − | ***begin_calibration() tells the sensor to go into calibration mode.
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| − | ***end_calibration() tells the sensor to leave calibration mode
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| − | | |
| − | * Example
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| − | compass = UltrasonicSensor(bot, PORT_1) #declare the sensor plugged into port 1 "compass"
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| − | heading = compass.get_sample()*2 # get the current heading in degrees from due north
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| − | | |
| − | * Notes
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| − | ** The sensor gives errors and fails to register almost all of the time. The reasoning for this is under investigation.
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| − | ** [http://www.hitechnic.com/cgi-bin/commerce.cgi?preadd=action&key=NMC1034 Compass Sensor hardware info]
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| − | ** URL to compass.py in source control (hint)
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| − | | |
| − | === Scripts ===
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| − | Located in <code>$DISTRIBUTION/scripts</code>.
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| − | * nxt_filer | |
| − | * nxt_push
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| − | * nxt_test
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| − | | |
| − | === Setup ===
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| − | ==== Ubuntu ====
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| − | | |
| − | If you are using Brad's livecd, make sure you have [http://cs.earlham.edu/~carrick/courses/cs282/cs282live_2.iso the latest version]
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| − | | |
| − | # Download [http://cs.earlham.edu/~carrick/courses/cs282/nxt.tgz Brad's installation kit] and untar it anywhere you want.
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| − | # In your editor of choice, modify the install.sh script to connect to your brick instead of Brad's. This will be within the first few lines.
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| − | # Open a terminal, navigate to the folder with your newly untarred files and type
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| − | sudo ./install.sh
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| − | If your computer supports bluetooth, set up your connection to your robot
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| − | # Turn on your brick.
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| − | # Navigate through the menu to enable bluetooth
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| − | #* Ensure that your device is set to "findable"
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| − | # Click the bluetooth symbol at the top of your computer's screen, next to the envelope.
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| − | # Select "Set up new device"
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| − | # Select your robot
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| − | # You will be prompted to input a passkey into your robot
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| − | #* Use the small grey button to delete characters and the large orange button to select characters
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| − | #* Select the checkmark to submit your passkey
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| − | #* Work quickly! You have about a minute before the passkey kicks you out and makes you start over!
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| − | #* You will be notified on-screen if your passkey was successful
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| − | # After your passkey is accepted, try running query.py
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| − | | |
| − | === Server Mode and nxt.server ===
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| − | === Tips ===
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| − | Wrap your code in a try/finally block so that you can stop the motors on control-c.
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| − | try:
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| − | [your code here]
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| − | finally:
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| − | [stop all your motors]
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