Create Presentation
Download Presentation

Download

Download Presentation

Compare the forward kinematics of a nonholonomic robot to those of a holonomic robot.

425 Views
Download Presentation

Download Presentation
## Compare the forward kinematics of a nonholonomic robot to those of a holonomic robot.

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -

**Compare the forward kinematics of a nonholonomic robot to**those of a holonomic robot.**Note that our textbook Craig will provide**a very useful and general way to develop the forward kinematics of a Holonomic robot.**EP**AP**Recall, that a holonomic robot will (kinematically)**“repeat”.**Recall, that a holonomic robot will (kinematically)**“repeat”. • In general, by returning the internal, servo-controlled angles to earlier, taught values, you will bring about a return of the borne load to its corresponding location in space.**Recall, that a holonomic robot will (kinematically)**“repeat”.**However there is a subtle distinction between holonomic**robots and nonholonomic robots that can be appreciated with this animation.**The nonholonomic robot will not repeat by merely returning**the internal angles of rotation to their previous values.**What is the nature of the forward kinematics of this**nonholonomic robot?**Let’s consider a “bird’s eye view” of the axis that**connects the wheelchair’s two wheels.**Development of nonholonomic equations for numerical**integration.**Imperfect tracking won’t affect the holonomic robot’s**terminal pose.**Imperfect tracking won’t affect the holonomic robot’s**terminal pose.**Imperfect tracking won’t affect the holonomic robot’s**terminal pose.**Imperfect tracking won’t affect the holonomic robot’s**terminal pose.**But imperfect tracking has a cumulative effect on the**nonholonomic robot.**But imperfect tracking has a cumulative effect on the**nonholonomic robot.**But imperfect tracking has a cumulative effect on the**nonholonomic robot.**But imperfect tracking has a cumulative effect on the**nonholonomic robot.**For all their disadvantages, nonholonomic, wheeled robots**offer some distinct advantages.**For all their disadvantages, nonholonomic, wheeled robots**offer some distinct advantages.**The wheelchair can get away with a three-degree-of-freedom**movement using just two servomechanisms, one for each wheel, precisely because it is a nonholonomic system.**How will we control such a robot if teach/repeat, the**standard for holonomic robots, cannot be applied?**One possibility is to track a line in the floor. But this**can get messy!**Also tracking of a physical line doesn’t permit deviation**from the path in the event of an obstacle.**You could track a wall instead.**• Many early developments of this kind. • Shakey • The Kent floor-cleaning robot**Alternatively, create sensor-based autonomy and reasoning,**such as “simultaneous localization and mapping”, SLAM.**So far SLAM methods have not produced much fruit. Hard to**achieve absent humans’ ability of object recognition. The “correspondence problem”.**EP**AP**Z-Y-X Euler Angles**- Just three numbers are needed to specify the orientation of one set of axes relative to another.**Z-Y-X Euler Angles**Just three numbers are needed to specify the orientation of one set of axes relative to another. One possible set of these numbers is the Z-Y-X Euler angles