### Tuesday 3:00: Machines in the lab <br> 3:30: Present <a href='../../lab/machine/drawing-machines.html' target="_self">drawing machine examples</a>. <br> <!-- 3:00: 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, pulleys, 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> --> <h3>Reading:</h3> Chapters 7-9 of <a href='http://mars1980.github.io/resources/making_things_move.pdf'> Making Things Move </a><br> MIT Course 2.75: FUNdaMENTALS of Design (Alex Slocum) <br> - <a href='https://nathanmelenbrink.github.io/lab/machine/FUNdaMENTALs/FUNdaMENTALs%20Topic%205.PDF' target="_self">Topic 5: Power Transmission Elements I</a> - <a href='https://nathanmelenbrink.github.io/lab/machine/FUNdaMENTALs/FUNdaMENTALs%20Topic%206.PDF' target="_self">Topic 6: Power Transmission Elements II</a> - Or [watch youtube videos](https://www.youtube.com/watch?v=wgMq7yha9wU&list=PLksE8LDXGXl_MQHKr2DqhfDC64W7QHjxL) <a href='https://forum.arduino.cc/index.php?topic=284828.0'>Arduino Forum Stepper Motor Basics</a><br> ### Thursday 3:00: Assignment Review <br> 3:30: <a href='../../lab/machine/steppers.html' target="_self">Stepper Motor Control</a> <br> 4:00: Begin design / assembly <br> <h3> Labs: </h3> Work on the group machine building assignment. By next week's lab, make sure that you can control the machine's locomotion. <h3> Group Assignment: </h3> Work with your [team](https://docs.google.com/spreadsheets/d/1ZBWiNdqdTK6IP4tdI9I8Gu-VUYGu3HmGd-Q0FT4GVrU/edit?usp=sharing) to build a 2+ DoF <a href='../../lab/machine/drawing-machines.html' target="_self">drawing machine</a>. Your team is encouraged to heavily modify the example hardware and software. At a minimum, you should implement a new end-effector. 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 perfect circle 6" and mark its center point Machine projects will be due Thursday April 18th. Be prepared to do a live demonstration for the class. After demonstrations, we will open voting for "students' choice awards" in the categories of (1) sophistication of drawing output (2) novelty of end-effector / drawing technique. Winning teams will be awarded perfect scores for the assignment. Please consolidate documentation to a single page for your group. Include a ~30-second demo video of your machine. ### 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> <br> <!-- <a href='https://forum.arduino.cc/index.php?topic=284828.0'>Arduino Forum Stepper Motor Basics</a><br> --> <!-- <a href='https://docs.google.com/presentation/d/1ZqWlTu3C6ChjgVlh-ZcghNG3y8bAC1Wpp0kyp3fGtFE/edit?usp=sharing'>Principles of Machine Design</a><br> --><!-- <a href='https://digital.library.cornell.edu/collections/kmoddl'>Reuleaux Kinematic Mechanisms Collection</a> (especially belt drive mechanisms)<br> <a href='https://cabaret.co.uk/'>Cabaret Mechanical Theatre</a><br> -->