Tool and Link Dimensions Menu
The device modules supplied by Adept Technology have been generalized so that they do not contain dimensional data for each link. This allows you to use the same device module for different sizes of the same robot. For example, when controlling a SCARA type mechanism, the lengths of the links are required. These link dimensions are user definable so that the user may control different sizes of SCARA mechanisms without requiring a different device module.
Because the link dimensions are not defined in the device module, you must specify them for mechanisms where they are required. The Tool and Link Dimensions Menu allows you to create the tool and link dimension specification. The options that appear on the menu are determined by the device module assigned to your mechanism. For example, the figure sample below shows the menu options when the LM device module is loaded. Note that this device module only requires dimensions for the Tool Z-offset since a linear module does not contain any joints.
When you select a menu option, the following information is provided on screen:
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Instructions for the specified option
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Current value
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Value range for the parameter if applicable
For details on a menu option, click the desired link in the following list to view the description:
Menu Options
Tool Z-Offset Distance
For robots which have a bending wrist, the tool offset distance defines the distance from the center of the wrist to the tool mounting flange. For example, in a five axis AdeptOne robot, the tool offset length is the distance from the intersection of axes 4 and 5 to the center of the joint 5 mounting flange. If a force sensing or compliant wrist is added to the robot, the tool offset length can be increased to account for the additional distance from axis 5 to the final mounting flange. By correcting the tool offset length in this fashion, the TOOL transformation can always be defined as the location of the tool tip relative to the end effector mounting flange.
Another application of the tool offset distance is to change the apparent height of a robot's tool flange. For example, with the X/Y/Z/Theta module, the Z-coordinate is initially considered 0 when the joint is at its 0 position (often fully retracted). This causes the robot's Z-coordinate to go negative as the Z-axis is extended. The tool offset distance can be adjusted to keep the Z-coordinate positive throughout robot's range of motion.
Refer to the device module documentation that is supplied with each device module for more specific information on the Tool Z-Offset distance.
Link Dimension Value #n
These specifications define the exact length of the robot's links and any other key dimensional factors which may be required. For some mechanisms (such as an X/Y/Z/Theta robot), no such dimensions need to be specified. In general, the number of values required to define the robot's size and their exact interpretation is a function of the robot's geometry and of the software implementation. Also, for computational efficiency, the required values may not always be pure
kinematics parameters but may be values that are computed from combinations of
kinematics parameters.
The SPEC utility prompts for the correct number of required dimensions, but you must use your device module documentation to see how to answer these prompts.
For robots which have a bending wrist, the tool offset distance defines the distance from the center of the wrist to the tool mounting flange. For example, in a five axis AdeptOne robot, the tool offset length is the distance from the intersection of axes 4 and 5 to the center of the joint 5 mounting flange. If a force sensing or compliant wrist is added to the robot, the tool offset length can be increased to account for the additional distance from axis 5 to the final mounting flange. By correcting the tool offset length in this fashion, the TOOL transformation can always be defined as the location of the tool tip relative to the end effector mounting flange.
Another application of the tool offset distance is to change the apparent height of a robot's tool flange. For example, with the X/Y/Z/Theta module, the Z-coordinate is initially considered 0 when the joint is at its 0 position (often fully retracted). This causes the robot's Z-coordinate to go negative as the Z-axis is extended. The tool offset distance can be adjusted to keep the Z-coordinate positive throughout robot's range of motion.
Refer to the device module documentation that is supplied with each device module for more specific information on the Tool Z-Offset distance.
These specifications define the exact length of the robot's links and any other key dimensional factors which may be required. For some mechanisms (such as an X/Y/Z/Theta robot), no such dimensions need to be specified. In general, the number of values required to define the robot's size and their exact interpretation is a function of the robot's geometry and of the software implementation. Also, for computational efficiency, the required values may not always be pure kinematics parameters but may be values that are computed from combinations of kinematics parameters.
The SPEC utility prompts for the correct number of required dimensions, but you must use your device module documentation to see how to answer these prompts.