### Agenda: <p> 12:00: Assignment Review <br> 12:30: Machine Showcase! We'll show some examples of machines that have been built in our lab. <ul> <li> <a href='../../lab/machine/machines.html' target="_self">Nathan's wooden machine kit </a> and <a href='http://nathanmelenbrink.com/20_vaultbot/1.mpg'>and VaultBot</a> </li> <li> <a href=''>Suvin's Bio-printer </a> </li> <li> <a href='https://gitlab.cba.mit.edu/neilg/urumbu'>Rob's Urumbu machines</a></li> <li> <a href='http://fab.cba.mit.edu/classes/863.21/Harvard/people/ibrahimibrahim/final/finalprogress.html'>Ibrahim's Rockbot </a> </li> <li> <a href='http://fab.cba.mit.edu/classes/863.21/Harvard/people/GabbyPerry/index.html'>Gabby's knitting machine </a> </li> <li> <a href='../../lab/machine/drawing-machines.html' target="_self">Drawing machine examples</a> </ul> 1:00: Break. Brainstorm end effector ideas with your machine group. <br> 1:15: Distribute drawing machine kits. Begin assembly, CAD design for end effectors, etc. <!-- 1:15: Workshop on <a href='../../lab/machine/steppers.html' target="_self">stepper motor control</a> and mechanical design <br> <ul> <li> Convert angular motion to linear motion (use shafts, belts, etc) </li> <li> Convert steps to mm (linear travel distance) accordingly </li> <li> Explore different microstepping modes </li> <li> Adjust motor speed and torque. What are the limits? </li> </ul> --> </p> <h3> Group Assignment: </h3> Work with your team to build a 2+ DoF <a href='../../lab/machine/drawing-machines.html' target="_self">drawing machine</a>. Drawing machines will need to demonstrate: - Ability to calibrate motor position (i.e. guarantee the "home" position is the same each time you power on the device) - Precision: ability to draw a circle and mark its center point. Calculate percent error. Machine projects will be due Thursday 7/31. Be prepared to do a live demonstration for the class. Please consolidate documentation to a single page for your group. Include a ~30-second demo video of your machine. <h3> Labs: </h3> <p> Work on group drawing machine assignment. </p> <h3>Reading:</h3> <p> Chapters 7-9 of <a href='http://mars1980.github.io/resources/making_things_move.pdf'> Making Things Move </a><br> <a href='https://forum.arduino.cc/index.php?topic=284828.0'>Arduino Forum Stepper Motor Basics</a><br> </p> ### Resources: Machines that have been built in our lab: - <a href='https://geometrikz.github.io/PS70/blog/week_10/'>Sidewalk Plotter </a> - <a href='https://clave963.github.io/PS70/10_machine/Week10_index.html'>Pen Plotter </a> - Kassia's Eye-Robot - <a href='http://fab.cba.mit.edu/classes/863.21/Harvard/people/ibrahimibrahim/final/finalprogress.html'>Ibrahim's Rockbot </a> - <a href='https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=10160345'>Gabby's Croche-Matic </a>