Final Review Hannah Lyness

Logistics Final Time: Friday, May 11th 10:00 AM Final Location: BH A51 You may use 2 sides of 1 8.5x11” paper written in your own hand Final value: 25% of final grade

Logistics (cont.) Test Coverage: Vision, Controls, Motion Planning, Graph Search, Localization, Basic Vehicle Design, Ballbot, Human Robot Interaction, Forward Kinematics, Inverse Kinematics, Terramechanics, Probabalistic Pose Estimation, Non-Holonomic Constraints Test Non-Coverage: Coding

Logistics (cont.) Likely test inclusions (subject to change) One problem based off the midterm Problems based on material since midterm Concept questions from the entire year (ex. “Pertaining to image thresholding, what information is described through a histogram?”, “Draw a path derived from the Bug 1 algorithm on a given image.”)

Vehicle Construction Weight distribution affects mobility Vehicle design affects turning radius http://www.fourwheeler.com/project-vehicles/154-0808-climbing-guide/photo-11.html

Vehicle Construction Gears can allow for manipulation of torque and speed High ground clearance and stability are both desirable and often in opposition. Hinged links can allow for non-circular motion. http://www.vias.org/feee/trans_03.html

Example Problem State one advantage of the vehicle on the left and one advantage of the vehicle on the right. https://www.youtube.com/watch?v=QKcxzTtvCQc, https://www.youtube.com/watch?v=XO6f8x3-uBc

Human-Robot Interaction Different applications require different HRI principles (ref. Prof Forlizzi’s presentation) Mutlu, Forlizzi: http://pages.cs.wisc.edu/~bilge/pubs/2008/HRI08-Mutlu.pdf

Study Review

Describing Translations and Rotations Relative motion is with respect to a coordinate system fixed to the body Absolute motion is with respect to a fixed world coordinate system Movements are not commutative Arun used what he called “hashing” to group measurements to get a more accurate guess of pose

Example Problem Draw a wedge that undergoes the following movements Absolute Translation 3 units y, rotation 90 deg x Rotation 90 deg x, translation 3 units y Relative

Forward Kinematics Description: using joint information, describe the end effector pose Complex configurations can be broken down into components t2 x,y l2 l2 l1 l1 t1 tf Given l1, l2, t1, t2 Find x, y, tf

Example Problem t2, w2 Front plane: l2 l1 T1, w1 Given l1, l2, t1, t2, w1, w2 We have a two joint robot with two-dimensional revolute joints. We describe each joint as having an angle component in the front yz plane (t) and in the right plane xy (w) (with no revolution or pivot along a line axial to the joint). What is the x,y,z location of the end effector of this robot?

Inverse Kinematics Description: using end effector information, find the joint characteristics When in doubt, make a new triangle l2 l1 x,y tf t2 l2 l1 t1 Given l1, l2, x, y, tf Find t1, t2

Example Problem X,y,θf Given x, y and theta of the end effector, find s, theta1 and theta2.

Non-Holonomic Constraints Motions that you can get in ways besides your initial describable motions

Non-Holonomic Constraints Start with states. Then describe constraints. Then describe allowable motions.

Example Problem Show that a bike can drive to any space in an empty parking lot. https://www.rei.com/learn/expert-advice/teach-child-to-ride-a-bike.html

https://www. rei. com/learn/expert-advice/teach-child-to-ride-a-bike https://www.rei.com/learn/expert-advice/teach-child-to-ride-a-bike.html