Robotics Class 2011/Assignment 4 - Revision history

Andrewtron3000 at 00:47, 8 September 2012

2012-09-08T00:47:21Z

← Older revision		Revision as of 00:47, 8 September 2012
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	'''cd''' to where you store your downloaded ROS packages		'''cd''' to where you store your downloaded ROS packages

	'''svn co http://hacdc-ros-pkg.googlecode.com/svn/trunk/irobotron_description'''		'''svn co http://hacdc-ros-pkg.googlecode.com/svn/trunk/irobotron_description'''

	'''rosmake irobotron_description'''		'''rosmake irobotron_description'''

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	'''roscd irobotron_description'''		'''roscd irobotron_description'''

	'''svn update'''		'''svn update'''

	'''rosmake irobotron_description'''		'''rosmake irobotron_description'''

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	'''cd''' to where you store your downloaded ROS packages		'''cd''' to where you store your downloaded ROS packages

	'''svn co http://hacdc-ros-pkg.googlecode.com/svn/trunk/museum_guard'''		'''svn co http://hacdc-ros-pkg.googlecode.com/svn/trunk/museum_guard'''

	'''rosmake museum_guard'''		'''rosmake museum_guard'''

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	'''cd''' to where you store your downloaded ROS packages		'''cd''' to where you store your downloaded ROS packages

	'''svn co http://hacdc-ros-pkg.googlecode.com/svn/trunk/face_detection'''		'''svn co http://hacdc-ros-pkg.googlecode.com/svn/trunk/face_detection'''

	'''rosmake face_detection'''		'''rosmake face_detection'''

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	'''alan_model::alan_link''' is at position '''(3.9, -0.14)'''		'''alan_model::alan_link''' is at position '''(3.9, -0.14)'''

	'''david_model::david_link''' is at position '''(4.0, 1.2)'''		'''david_model::david_link''' is at position '''(4.0, 1.2)'''

	'''david2_model::david2_link''' is at position '''(3.8, 2.3)'''		'''david2_model::david2_link''' is at position '''(3.8, 2.3)'''

	'''eric_model::eric_link''' is at position '''(1.6, 4.0)'''		'''eric_model::eric_link''' is at position '''(1.6, 4.0)'''

	'''erica_model::erica_link''' is at position '''(2.7, 5.1)'''		'''erica_model::erica_link''' is at position '''(2.7, 5.1)'''

	'''jeff_model::jeff_link''' is at position '''(4.0, 6.4)'''		'''jeff_model::jeff_link''' is at position '''(4.0, 6.4)'''

	'''john_model::john_link''' is at position '''(3.9, 8.7)'''		'''john_model::john_link''' is at position '''(3.9, 8.7)'''

	'''phil_model::phil_link''' is at position '''(2.5, 9.6)'''		'''phil_model::phil_link''' is at position '''(2.5, 9.6)'''

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	'''x''' = 0.0		'''x''' = 0.0

	'''y''' = 0.0		'''y''' = 0.0

	'''z''' = 0.707		'''z''' = 0.707

	'''w''' = 0.707		'''w''' = 0.707


	This quaternion represents a (pi/2) radian rotation about the ''z'' axis (a yaw). This ends up pointing us left. It is easy to convert between the notion of a yaw and a quaternion. One way is to [http://www.wolframalpha.com/input/?i=euler+angles&a=C.euler+angles-_Formula.dflt-&a=*FP.EulerRotation.EAS-_e321&f3=Pi+%2F+2+radians&x=0&y=0&f=EulerRotation.th1_Pi+%2F+2+radians&f4=0&f=EulerRotation.th2_0&f5=0&f=EulerRotation.th3_0 type "euler angles" into Wolfram Alpha]. Doing this gives you a nice conversion utility. There are a couple important things to remember when using this conversion utility. The first is to make sure you select the "Euler rotation sequence" and enter your rotations in such that you only request a yaw rotation. Also, when the computation is finished, the desired quaternion parameters are in the box named "Euler parameters (quaternions)", with the convention that the parameters are specified as:		This quaternion represents a (pi/2) radian rotation about the ''z'' axis (a yaw). This ends up pointing us left. It is easy to convert between the notion of a yaw and a quaternion. One way is to [http://www.wolframalpha.com/input/?i=euler+angles&a=C.euler+angles-_Formula.dflt-&a=*FP.EulerRotation.EAS-_e321&f3=Pi+%2F+2+radians&x=0&y=0&f=EulerRotation.th1_Pi+%2F+2+radians&f4=0&f=EulerRotation.th2_0&f5=0&f=EulerRotation.th3_0 type "euler angles" into Wolfram Alpha]. Doing this gives you a nice conversion utility. There are a couple important things to remember when using this conversion utility. The first is to make sure you select the "Euler rotation sequence" and enter your rotations in such that you only request a yaw rotation. Also, when the computation is finished, the desired quaternion parameters are in the box named "Euler parameters (quaternions)", with the convention that the parameters are specified as:

	'''beta_0''' is '''w'''		'''beta_0''' is '''w'''

	'''beta_1''' is '''x'''		'''beta_1''' is '''x'''

	'''beta_2''' is '''y'''		'''beta_2''' is '''y'''

	'''beta_3''' is '''z'''		'''beta_3''' is '''z'''

ITechGeek at 20:46, 3 April 2012

2012-04-03T20:46:14Z

← Older revision		Revision as of 20:46, 3 April 2012
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			[[Category:RobotClass]]

	The rumor is that something bad is going on in the secret underground HacDC antiquities warehouse. The security guards have written a memo describing recent sightings of artifacts in the warehouse "moving by themselves". They have come to us, the robotics experts, to see if we can provide them with a robot that can make the rounds in the warehouse keeping an eye out for mysterious paranormal activities.		The rumor is that something bad is going on in the secret underground HacDC antiquities warehouse. The security guards have written a memo describing recent sightings of artifacts in the warehouse "moving by themselves". They have come to us, the robotics experts, to see if we can provide them with a robot that can make the rounds in the warehouse keeping an eye out for mysterious paranormal activities.

Andrewtron3000 at 17:40, 1 April 2012

2012-04-01T17:40:16Z

← Older revision		Revision as of 17:40, 1 April 2012
Line 103:		Line 103:
	This quaternion represents a (pi/2) radian rotation about the ''z'' axis (a yaw). This ends up pointing us left. It is easy to convert between the notion of a yaw and a quaternion. One way is to [http://www.wolframalpha.com/input/?i=euler+angles&a=C.euler+angles-_Formula.dflt-&a=*FP.EulerRotation.EAS-_e321&f3=Pi+%2F+2+radians&x=0&y=0&f=EulerRotation.th1_Pi+%2F+2+radians&f4=0&f=EulerRotation.th2_0&f5=0&f=EulerRotation.th3_0 type "euler angles" into Wolfram Alpha]. Doing this gives you a nice conversion utility. There are a couple important things to remember when using this conversion utility. The first is to make sure you select the "Euler rotation sequence" and enter your rotations in such that you only request a yaw rotation. Also, when the computation is finished, the desired quaternion parameters are in the box named "Euler parameters (quaternions)", with the convention that the parameters are specified as:		This quaternion represents a (pi/2) radian rotation about the ''z'' axis (a yaw). This ends up pointing us left. It is easy to convert between the notion of a yaw and a quaternion. One way is to [http://www.wolframalpha.com/input/?i=euler+angles&a=C.euler+angles-_Formula.dflt-&a=*FP.EulerRotation.EAS-_e321&f3=Pi+%2F+2+radians&x=0&y=0&f=EulerRotation.th1_Pi+%2F+2+radians&f4=0&f=EulerRotation.th2_0&f5=0&f=EulerRotation.th3_0 type "euler angles" into Wolfram Alpha]. Doing this gives you a nice conversion utility. There are a couple important things to remember when using this conversion utility. The first is to make sure you select the "Euler rotation sequence" and enter your rotations in such that you only request a yaw rotation. Also, when the computation is finished, the desired quaternion parameters are in the box named "Euler parameters (quaternions)", with the convention that the parameters are specified as:

	'''~~q_0~~''' is '''w'''		'''beta_0''' is '''w'''
	'''~~q_1~~''' is '''x'''		'''beta_1''' is '''x'''
	'''~~q_2~~''' is '''y'''		'''beta_2''' is '''y'''
	'''~~q_3~~''' is '''z'''		'''beta_3''' is '''z'''

	You can then take these parameters and copy them into your navigation goal, and hopefully the robot should do what you command!		You can then take these parameters and copy them into your navigation goal, and hopefully the robot should do what you command!

Andrewtron3000 at 01:27, 18 July 2011

2011-07-18T01:27:52Z

← Older revision		Revision as of 01:27, 18 July 2011
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	This command will insert the robot into the starting location in the map. It may be hard to see the robot, but if you use the mouse to navigate in the gazebo window, you will find the robot 10 grid squares (meters) forward and one grid square (meter) left of the initial gazebo starting coordinates.		This command will insert the robot into the starting location in the map. It may be hard to see the robot, but if you use the mouse to navigate in the gazebo window, you will find the robot 10 grid squares (meters) forward and one grid square (meter) left of the initial gazebo starting coordinates.

	Once you have the robot in the simulation, you need to add the museum artifacts into the simulation. You can insert them into the simulation with the following command:		Once you have the robot in the simulation, you need to add the museum artifacts into the simulation. Assignment 3 included instructions on how to check out the floating_faces package from the HacDC ROS repository. You can insert them into the simulation with the following command:

	'''roslaunch floating_faces faces_in_office2.launch'''		'''roslaunch floating_faces faces_in_office2.launch'''

Andrewtron3000 at 01:25, 18 July 2011

2011-07-18T01:25:03Z

← Older revision		Revision as of 01:25, 18 July 2011
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	'''w''' = 0.707		'''w''' = 0.707

	This quaternion represents a (pi/2) radian rotation about the ''z'' axis (a yaw). This ends up pointing us left. It is easy to convert between the notion of a yaw and a quaternion. One way is to ~~type "euler angles" into~~ [http://www.wolframalpha.com/ Wolfram Alpha]. Doing this gives you a nice conversion utility. There are a couple important things to remember when using this conversion utility. The first is to make sure you select the "Euler rotation sequence" and enter your rotations in such that you only request a yaw rotation. Also, when the computation is finished, the desired quaternion parameters are in the box named "Euler parameters (quaternions)", with the convention that the parameters are specified as:		This quaternion represents a (pi/2) radian rotation about the ''z'' axis (a yaw). This ends up pointing us left. It is easy to convert between the notion of a yaw and a quaternion. One way is to [http://www.wolframalpha.com/input/?i=euler+angles&a=C.euler+angles-_Formula.dflt-&a=*FP.EulerRotation.EAS-_e321&f3=Pi+%2F+2+radians&x=0&y=0&f=EulerRotation.th1_Pi+%2F+2+radians&f4=0&f=EulerRotation.th2_0&f5=0&f=EulerRotation.th3_0 type "euler angles" into Wolfram Alpha]. Doing this gives you a nice conversion utility. There are a couple important things to remember when using this conversion utility. The first is to make sure you select the "Euler rotation sequence" and enter your rotations in such that you only request a yaw rotation. Also, when the computation is finished, the desired quaternion parameters are in the box named "Euler parameters (quaternions)", with the convention that the parameters are specified as:

	'''q_0''' is '''w'''		'''q_0''' is '''w'''

Andrewtron3000 at 23:05, 16 July 2011

2011-07-16T23:05:19Z

← Older revision		Revision as of 23:05, 16 July 2011
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	'''phil_model::phil_link''' is at position '''(2.5, 9.6)'''		'''phil_model::phil_link''' is at position '''(2.5, 9.6)'''

	Note to make the assignment slightly harder, some of the artifacts are on different walls than the first artifact. This requires you to specify navigation goals in your smach state machine that have not only a target position, but also a target attitude, specified as a quaternion. The navigation goal provides an orientation in the goal that specifies the robot ending attitude. Based on the robot's coordinate system of ''x'' being forward, ''y'' to the left, and ''z'' up, when we want to end in a different orientation, we must specify an ending rotation about ''z'', called ''yaw''. For example, to get the quaternion for the robot to be facing to the left of its original position in the map, we would provide a quaternion to the navigation stack of the form:		Note to make the assignment slightly harder, some of the artifacts are on different walls than the first artifact. This requires you to specify navigation goals in your smach state machine (smach_guard.py in the museum_guard ROS package obtained above) that have not only a target position, but also a target attitude, specified as a quaternion. The navigation goal provides an orientation in the goal that specifies the robot ending attitude. Based on the robot's coordinate system of ''x'' being forward, ''y'' to the left, and ''z'' up, when we want to end in a different orientation, we must specify an ending rotation about ''z'', called ''yaw''. For example, to get the quaternion for the robot to be facing to the left of its original position in the map, we would provide a quaternion to the navigation stack of the form:

	'''x''' = 0.0		'''x''' = 0.0

Andrewtron3000 at 23:03, 16 July 2011

2011-07-16T23:03:05Z

← Older revision		Revision as of 23:03, 16 July 2011
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	'''rosmake face_detection'''		'''rosmake face_detection'''

	Assignment 2 discusses ~~face_detection~~ in more detail.		Assignment 2 discusses face detection in more detail.

	Once the face_detector is available, you can start it as follows:		Once the face_detector is available, you can start it as follows:

Andrewtron3000 at 23:01, 16 July 2011

2011-07-16T23:01:34Z

← Older revision		Revision as of 23:01, 16 July 2011
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	'''roslaunch irobotron_description create_mobile_base_in_office2.launch'''		'''roslaunch irobotron_description create_mobile_base_in_office2.launch'''

	This command will insert the robot into the starting location in the map. It may be hard to see the robot, but if you use the mouse to navigate in the gazebo window, you will find the robot 10 meters forward and one meter left of the initial gazebo starting coordinates.		This command will insert the robot into the starting location in the map. It may be hard to see the robot, but if you use the mouse to navigate in the gazebo window, you will find the robot 10 grid squares (meters) forward and one grid square (meter) left of the initial gazebo starting coordinates.

	Once you have the robot in the simulation, you need to add the museum artifacts into the simulation. You can insert them into the simulation with the following command:		Once you have the robot in the simulation, you need to add the museum artifacts into the simulation. You can insert them into the simulation with the following command:

Andrewtron3000 at 22:41, 16 July 2011

2011-07-16T22:41:30Z

← Older revision		Revision as of 22:41, 16 July 2011
Line 29:		Line 29:
	These artifacts are in the same locations as the real artifacts in the secret HacDC antiquities warehouse.		These artifacts are in the same locations as the real artifacts in the secret HacDC antiquities warehouse.

	Next you can then start the ROS navigation stack to allow the robot to be able to navigate autonomously throughout the warehouse. There is a launch file that has been written that customizes the ROS navigation stack for our particular robot~~. You can look at the launch file, named move_base.launch, for more info~~. To start the navigation stack, type:		Next you can then start the ROS navigation stack to allow the robot to be able to navigate autonomously throughout the warehouse. There is a launch file that has been written that customizes the ROS navigation stack for our particular robot. To start the navigation stack, type:

	'''roslaunch irobotron_description move_base.launch'''		'''roslaunch irobotron_description move_base.launch'''

Andrewtron3000 at 22:15, 16 July 2011

2011-07-16T22:15:01Z

← Older revision		Revision as of 22:15, 16 July 2011
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	'''q_2''' is '''y'''		'''q_2''' is '''y'''
	'''q_3''' is '''z'''		'''q_3''' is '''z'''

			You can then take these parameters and copy them into your navigation goal, and hopefully the robot should do what you command!

			Good luck on the assignment and happy ghost hunting!

			[http://wiki.hacdc.org/index.php/Robotics_Class_2011 Back to Robotics Class 2011]

			[http://www.youtube.com/watch?v=Qka5HX-R-cQ Secret bonus video (slyt)]