Mechanism Teaching Board

thingiverse

The Model:\nThis teaching mechanism uses a common A3 sized pegboard as a base to connect all mechanism models together. The mechanism models provide a useful teaching resource to help students understand how mechanisms work and how particular ones convert or reduce/increase various types of motion.\nThe board, once assembled, includes models of 4 different cam types, the 3 classes of lever, two different pulley setups, a simple gear system, and a compound gear system. \nThe Project:\nIn my classes (Engineering, ages 14-16) students learn about mechanisms and how they work, and are then asked to design and construct a toy that uses at least one mechanism. Mechanism in this context is explored as something that converts one type of motion to another (linear, rotary, osculating, reciprocating, etc). Most students design models of their mechanical toys using various CAD programs to get a visual understanding of what they need to build.\nPrint Settings\nPrinter Brand: Up!\nPrinter: Up Mini\nRafts: Doesn't Matter\nSupports: Yes\nResolution: 0.2 - 0.25\nInfill: 8-12%\nNotes: These are all designed to print in place. If printed face down, no support is required. If printed face up, a significant amount of support is required.\nPost-Printing\nRemove prints / clean up if required. Ensure print in place pivots are working. Push into peg board in relevant holes.\nHow I Designed This\nDesigned using Solidworks and Autodesk Inventor\nThe mechanisms are built individually and assembled in Solidworks. The print in place pivot point on all mechanisms sits flush with the front face, so they can be printed face down requiring no support. My printer looks much nicer on the top side than the bottom side, so I printed them face up with supports to hold up the entire cam/gear/pulley/lever while the pegboard pin stood underneath.\nGaps used in the print in place parts are set to 0.25mm, keep this in mind when choosing your layer height.\nProject: Mechanical Toy\nObjectives\nStudents are expected to learn about:\nThe nature and purpose of mechanisms\nThe components that make up mechanisms\nThe function and operation of mechanisms such as levers, pulleys, gears and cams\nFriction and its significance to the operation of mechanisms\nMechanical Advantage, velocity ratio and efficiency in mechanisms\nMethods of driving mechanisms\nStudents are expected to learn to:\nDismantle and assemble mechanisms to understand how they work\nDesign and construct mechanisms for specific purposes\nCarry out experiments to demonstrate engineering principles\nAudiences\nThis project is suitable for students aged 13-16 who are studying a course related to mechanisms, science, engineering, maths, technology, design, woodwork, etc.\nPreperation\nPrior knowledge required includes understanding and calculating ratios and understanding different types of motion.\nThe project outlined here would consist of either 3D Modelling/Printing or woodwork/plastics construction. In this case it would require, respectively:\nComputer, CAD Software of your choosing, 3D Printer, ample filament, etc\nTimber for construction, relevant hand tools or machinery for working timber, perspex or other plastics for construction, relevent hand tools or machinery for working plastic.\nSteps!\nThis project can be quite simple or quite detailed depending on how you'd like to run it. A suggested workflow:\n1) Confirm prior knowledge of ratios and calculation\n2) Confirm prior knowledge of motion principles\n3) Use above Mechanism Teaching Board to teach about mechanisms and how they work\n4) Design various design solutions and coming up with toy ideas\n5) Create hand drawings of ideas, detailing the mechanisms that will be used. Identify input motion point and type, and output motion point and type\n6) Develop a materials list and/or steps of construction\n7) Create CAD Model/3D Print and/or begin workshop construction\n8) Assemble toy\n9) Testing and Project Evaluation\nResults\nAt the end of the project students would have designed and constructed and mechanical toy out of either 3D Printed plastic or construciton using wood/plastic based on knowledge they have developed regarding motion and mechanisms. Suggestion for grading and assessment of the function of the toy:\nTell the students you will conduct the required "input motion" 10 times, and award 1 mark for each successful "output motion". For example, a toy wherein you turn a handle in rotary motion (input) to move a figurine up and down on top of the toy (output) you would turn that handle 10 times, and for each succesful up and down motion of the figurine, they are awarded 1 mark.