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| ece4560:lynx6:calibration [2017/10/22 16:55] – pvela | ece4560:lynx6:calibration [2024/08/20 21:38] (current) – external edit 127.0.0.1 |
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| reference configuration. Calibration will require measuring the link lengths associated to your manipulator, the servo command limits for each of the joints, and the angular limits of the manipulator. The limits imposed may actually be less than the full range of motion of the servo motors. The sub-problems below lead you through the procedure. | reference configuration. Calibration will require measuring the link lengths associated to your manipulator, the servo command limits for each of the joints, and the angular limits of the manipulator. The limits imposed may actually be less than the full range of motion of the servo motors. The sub-problems below lead you through the procedure. |
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| - Measure the lengths of all the links. Make sure to include the wooden base in your measurements for vertical height as appropriate. Try to be as accurate as possible since mistakes here will impact your ability to do useful things with the manipulator. \\ There is a member variable in the {\tt lynx6} class object for specifying these variables. They've been set based on my setup, but may be different for yours. The numbers in the list are the base to should height, the length of the first link, the length of the second link, then the link to middle of gripper length, and the additional length to gripper tip. | - Measure the lengths of all the links. Make sure to include the base in your measurements for vertical height as appropriate. Try to be as accurate as possible since mistakes here will impact your ability to do useful things with the manipulator. \\ There is a member variable in the {\tt lynx6} class object for specifying these variables. They've been set based on my setup, but may be different for yours. The numbers in the list are the base to shoulder height, the length of the first link, the length of the second link, then the link to middle of gripper length, and the additional length to gripper tip. |
| - Determine what are the proper servo command limits for your particular manipulator. The manipulator code for interfacing should be uploaded to {\tt t-square} as will a file describing in more detail what this problem is about. Please read the document twice and be careful, they break easily. | - Determine what are the proper servo command limits for your particular manipulator. The manipulator code for interfacing is located [[ECE4560:ManiControl | here]] with links describing in more detail what calibration entails. Please read the document twice and be careful, as the manipulators break easily. |
| - The last phase is to associate angles to the servo commands. Using the straight-up reference configuration as the zero configuration for the joint-angles, determine the angular limits associated to the joints with respect to that reference configuration as best as you can. You *will* need a protractor. \\ Although the robot may be able to go to bigger angles, try to round the joint-angle workspace to the nearest 30, 45, 90, or 180 degrees. For example, if you measure that it can go -37 degrees to 48 degrees, then make the joint angle limits $[-30, 45]$ in order to have nice clean limits. You'll need to figure out what servo commands correspond to those particular angle limits. | - The last phase is to associate angles to the servo commands. Using the straight-up reference configuration as the zero configuration for the joint-angles, determine the angular limits associated to the joints with respect to that reference configuration as best as you can. You *will* need a protractor. \\ Although the robot may be able to go to bigger angles, try to round the joint-angle workspace to the nearest 30, 45, 90, or 180 degrees. For example, if you measure that it can go -37 degrees to 48 degrees, then make the joint angle limits $[-30, 45]$ in order to have nice clean limits. You'll need to figure out what servo commands correspond to those particular angle limits. |
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| Save it into your own file whose default is called ''lynx6parms.mat'' for use with the ''lynx6'' class file. Turn in the values of the structure in the ''lynx6parm'' matlab file as well as your link lengths. Some folk have been turning in a screenshot of the calibration dialog window. That works too (''Ctrl-PrintScreen'' will capture it and ''Ctrl-V'' will paste the image). If you do it right, you might even be able to load the image file, display it in a Matlab figure, then have it be output as part of the ''publish'' execution. | |
| | Save it into your own file whose default is called ''lynx6parms.mat'' for use with the ''lynx6'' class file. Turn in the values of the structure in the ''lynx6parm'' matlab file as well as your link lengths. Some folk have been turning in a screenshot of the calibration dialog window. That works too (''Ctrl-PrintScreen'' will capture it and ''Ctrl-V'' will paste the image). If you save the screen capture to an image file, you should even be able to load the image file, display it in a Matlab figure, then have it be output as part of the ''publish'' execution. |
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| ==== Demo: Verification ==== | ==== Demo: Verification ==== |
