Day 4: (Mon Sep 12, Week 3) Mechanical Components

Notes for 2022-09-12.

New Assignments

  1. New assignment, due in a week: Exercise: Actuated Marble Run Tile

  2. In general, when uploading a video or zip file, please include your name or Andrew ID in the title since I often download them and it helps me track the files.

Administrative

  • A few students reported trouble with laser cutter access. Please be sure to follow through on qualifications as per IDeATe Laser Cutter Policies. If you have specific access problems, please immediately email help@ideate.cmu.edu with a detailed request for help. In the short term, please also be aware of IDeATe Open Fabrication Hours.

  • If you were unable to finish the assignment due to laser cutter access problems, please obtain access and complete your device by Wednesday. You will also need to create a short documentation video of it operating with marbles and include that in your post.

  • Each student is required to report their vaccination status to the Children’s School, either via form to your instructor or via email to Kelly Delaney. Please answer the following one-question form before the end of the day: CKS Vaccination Report.

Agenda

  1. In-class testing of the marble run tiles.

    1. Can we discover some combinations of tiles which work well together?

    2. What can be observe about the effects of varying the slope?

    3. What new designs do the results suggest?

  2. Quick review of SolidWorks part and sketch terminology.

  3. More SolidWorks tips: part configurations, sketch blocks.

  4. Working with SolidWorks assemblies.

    1. Mates

    2. Simulating joints with unconstrained freedoms.

    3. Four-bar linkage example.

    4. Assemblies and external dependencies.

    5. Actuated tile example.

    6. Importing standard parts.

      1. Physical Computing Lab Inventory

      2. McMaster-Carr

  5. Lab part show and tell.

    1. F22 Course Kit

    2. Visual Part Guides

    3. SolidWorks files on course site

    4. Sample Mechanical Designs

    5. Pivots and bearings

      • clevis pin

      • cotter pin

      • bushing

      • shoulder screw

      • ball bearing

    6. Fasteners

      • M3 machine screw

      • washer

      • self-tapping sheet metal screw

      • standoff, spacer

      • dowel pin

      • wire tie

    7. Components

      • spring

      • O-ring

    8. adhesives

SolidWorks Terminology of the Day

For more, please see SolidWorks Parametric CAD word list.

  • mate

  • fixed, float

  • in-context feature

  • component pattern

Figures

../_images/four-bar-linkage.PNG

Four-bar linkage example, abstracted to simple link shapes. In the sample actuated tile above the ‘ground’ link role is played by the base, the input rocker is the servo horn, the output rocker is the ball driver, and the connecting link is a wire tie rod.