ME 8: Design and Manufacturing

Proof required

Link the public repo with the three 2.007 problem sets (design process and machine elements; servomotors, mechanisms and CAD; pneumatics, CAD and gears) written up (a typeset PDF, LaTeX source or notebook), and show the self-check: which answers matched and how you fixed the ones that did not.

What gets checked

• Each design choice is backed by a calculation or a sketch.
• Motor answers check torque and speed against the load.
• Answers match the published solutions, and misses are reworked.

Common mistakes

• Answers copied from a solution with no working.
• Missing units, or a free-body diagram or sign convention left out.

Powstik Guide

A public write-up of the three 2.007 problem sets (design process and machine elements; servomotors, mechanisms and CAD; pneumatics, CAD and gears), with the self-check shown.

Steps

1. Study the linked course material.
2. Solve the problems on your own first.
3. Check them against the self-check and rework the misses.
4. Typeset the write-up (LaTeX or a notebook) in a public repo.
5. Ask someone who knows the subject to check it.

README
ME 8: Design and Manufacturing, unit 1: The design process, mechanisms and actuators
Problems:
Self-check result (matched / reworked):
What I got wrong first and why:

What gets sent back

• No working shown.
• The self-check result is missing.

Resources

What a verifier looks for

• Each design choice is backed by a calculation or a sketch.
• Motor answers check torque and speed against the load.
• Answers match the published solutions, and misses are reworked.
• Is the engineering right, not just the final number?

You'll sign in first, then come straight back here.

Proof required

Link the public repo with the 2.008 practice Quiz 1 papers (2021–2024) written up (a typeset PDF, LaTeX source or notebook), and show the self-check: which answers matched and how you fixed the ones that did not.

What gets checked

• Cutting forces and times are worked from stated speeds and feeds.
• Moulding answers check cycle time from cooling.
• Each practice quiz is marked against its solutions, with the score stated.

Common mistakes

• Answers copied from a solution with no working.
• Missing units, or a free-body diagram or sign convention left out.

Powstik Guide

A public write-up of the 2.008 practice Quiz 1 papers (2021–2024), with the self-check shown.

Steps

1. Study the linked course material.
2. Solve the problems on your own first.
3. Check them against the self-check and rework the misses.
4. Typeset the write-up (LaTeX or a notebook) in a public repo.
5. Ask someone who knows the subject to check it.

README
ME 8: Design and Manufacturing, unit 2: Manufacturing processes: machining, moulding and forming
Problems:
Self-check result (matched / reworked):
What I got wrong first and why:

What gets sent back

• No working shown.
• The self-check result is missing.

Resources

What a verifier looks for

• Cutting forces and times are worked from stated speeds and feeds.
• Moulding answers check cycle time from cooling.
• Each practice quiz is marked against its solutions, with the score stated.
• Is the engineering right, not just the final number?

You'll sign in first, then come straight back here.

Proof required

Link the public repo with the 2.008 practice Quiz 2 papers (2021–2024) written up (a typeset PDF, LaTeX source or notebook), and show the self-check: which answers matched and how you fixed the ones that did not.

What gets checked

• Cost models separate fixed and per-part costs and find the break-even quantity.
• Quality answers use process capability (Cp, Cpk) with stated limits.
• Each practice quiz is marked against its solutions, with the score stated.

Common mistakes

• Answers copied from a solution with no working.
• Missing units, or a free-body diagram or sign convention left out.

Powstik Guide

A public write-up of the 2.008 practice Quiz 2 papers (2021–2024), with the self-check shown.

Steps

1. Study the linked course material.
2. Solve the problems on your own first.
3. Check them against the self-check and rework the misses.
4. Typeset the write-up (LaTeX or a notebook) in a public repo.
5. Ask someone who knows the subject to check it.

README
ME 8: Design and Manufacturing, unit 3: Process planning, cost, quality and assembly
Problems:
Self-check result (matched / reworked):
What I got wrong first and why:

What gets sent back

• No working shown.
• The self-check result is missing.

Resources

What a verifier looks for

• Cost models separate fixed and per-part costs and find the break-even quantity.
• Quality answers use process capability (Cp, Cpk) with stated limits.
• Each practice quiz is marked against its solutions, with the score stated.
• Is the engineering right, not just the final number?

You'll sign in first, then come straight back here.

Proof required

Link the public repo with the sketch and prediction, build photos, a video shorter than 2 minutes and the predicted-vs-measured table, and a README that says how to rerun it and what limits the result.

What gets checked

• The sketch, the prediction script or calculation, and the build photos are in the repo.
• A video shorter than 2 minutes shows the full motion with a scale in frame.
• The predicted-vs-measured table covers eight positions, with each gap explained.

Common mistakes

• A result that nobody else can rerun from the repo.
• A table with no explanation of the gaps.

Powstik Guide

A working mechanism built with hand tools (for example a four-bar linkage or a crank-slider made from card, wood strips and paper fasteners) with a short video, in a public repo.

Steps

1. Write down what you expect before you start.
2. Sketch the mechanism, state whether it meets the Grashof condition, and predict its output motion (angle or stroke against crank angle) by hand or in a short Python script. Build it with hand tools only: scissors, a craft knife on a cutting board (cut away from your hand) and an awl or hand drill for pivot holes. Film it next to a ruler or protractor and read the output at eight input positions. Fill a predicted-vs-measured table and explain the gaps (joint play, link length error, flex).
3. Fill the predicted-vs-measured (or hand-vs-simulated) table.
4. Explain every gap with a cause someone can check.
5. Write the README and ask someone who knows the subject to check it.

README
ME 8: Design and Manufacturing — Design, build and film a mechanism
What I expected:
How to rerun it:
Predicted vs measured:
Why they differ:
Safety: hand tools and eye protection only

What gets sent back

• No video, or no prediction to compare against.
• Machine tools, welding, pressure vessels, combustion, or springs and flywheels storing dangerous energy without a trained supervisor.

Resources

What a verifier looks for

• The sketch, the prediction script or calculation, and the build photos are in the repo.
• A video shorter than 2 minutes shows the full motion with a scale in frame.
• The predicted-vs-measured table covers eight positions, with each gap explained.
• Check the engineering and the numbers, not just that it exists: do the units, the hand calculation and the table agree?
• Build photos show hand tools only and eye protection worn: no machine tools, welding, pressure vessels, combustion, or springs and flywheels storing dangerous energy (unless a trained supervisor and a proper workshop are shown).

You'll sign in first, then come straight back here.