Engineering: Time Machine

Note:  We have these 3 articles courtesy of UC ILL.  Mr. Sorensen has uploaded them to Canvas.

"Feedback Control in Ancient Water and Mechanical Clocks"
IEEE Xplore Digital Library

"On the Dynamics of the Escapement Mechanism of a Mechanical Clock"
IEEE Xplore Digital Library

NIST also posts technical reports and monographs:
"Time and Frequency Metrology:  Fundamental Concepts"
Raul Solis

Hewlett Packard application note
"The Science of Timekeeping"
David W. Allan, Neil Ashby, Clifford C. Hodge
1997

"A Brief History of Telling Time"
The Conversation

Additional articles are available by searching our databases!

ProjectClock.org

Clickspring  channel on YouTube
"How to Make A Clock in the Home Machine Shop" series
 

• Walk through Time:  Early Measurement
• A Revolution in Timekeeping
• Time and Frequency

• Clockwork (windup) mechanisms

• Pendulum clocks
• Water powered clocks

Design Problem: Design and Build a timing device that can measure a 10 minute interval to an accuracy of +/-5% (+/-30 seconds)

Design constraints:

• Design must have a maximum footprint of 11" x 16" and a maximum height of 12". (Must fit in a box lid inside a small cubby near the door.)
• Pre-existing parts may be used, but those parts CANNOT interact with any other parts from the source of that part or a source of the same "kind".
  • For the purposes of this design, a single "part" will be any part that is removable by reasonable means from other parts.
  • If you decide to utilize an hour-glass type design, you may not use a pre-existing hour glass shape.
• The device itself must clearly indicate when 10 minutes has been measured
• Prior to testing day, you must run and record 5 separate trials of your device attempting to measure a 10 minute time interval.
• Arduinos may be used, but only to assist in counting a repeating pattern of the main device and communicating what that count is. The Arduino cannot be used to do any timing.
• If an hour glass is used, it may only be responsible for timing a maximum of 7 of the 10 minutes.

Timing:

• You will have 8 days to complete the project and prepare your presentation.
• No building will be done on the first two days of the project. Those days will be for research, brainstorming, project planning, and project drawings. We will all be in our classroom during those first two days.

Official final testing:

• Will take place at the beginning of Day 9.
• There will be a 5 minute set-up period and then timing will begin.
• All devices in that class will start and end at that same time
• Official final timing device will be my cell phone.
• For your prior 5 trials, it is safe to assume that your phones are timing devices with similar accuracy and precision to my phone.

Presentations

• Presentations will begin on Day 9
• You will have a 5 minute period after official testing is completed to modify your presentation with your timing data and conclusions based on that data
• A presentation rubric will be supplied to you at the beginning of the project

Responsibilities for clarification of any questions:

• If you have any issues with interpretation of the meaning of this document, you need to ask.
• Mr. Sorensen will be the final decision maker about the interpretation of the design constraints. My purpose is to preserve an appropriate level of challenge for the project.

• Grandfather clocks - gravitational potential energy driven pendulum clocks
• Water clocks
• Chronographs - spring driven mechanisms
• Hour glasses
• Marble Machines
• Pythagora Switches   

• Specific names of time keeping mechanisms listed above
• Horology - theory and application
• Metrology
• Timekeeping
• Time measurement
• Clocks - design and construction
• Hourglass - also ampolletas (Spanish), clepsammia, sand clock, marine sandglass
• Mechanical Clocks
  Weight driven mechanical clocks
  Spring driven mechanical clocks
• Water clock - also clepsydra (Greek) also Time Flow clock
  If you search specifically for clepsydra, you will get more focused articles. 
  Example: "When Time Flowed:  the History of Clepsydra"
  If you search for Time Flow Clock you will get a very different set of returns.
  Artist / physicist Bernard Gitton is renowned for his "time flow clocks."  Here is a sample article that explains the concepts behind them:
  "Inspiration: The Water Clocks of Bernard Gitton"
   

Research Tip:
Read the 2008 ASME paper by Wagner, Huey & Knaub: "Clock Mechanism Fundamentals for Education: Modeling and Analysis"  (Posted in Canvas).  Mine the article for subject specific keywords and fundamental engineering concepts).  Use these terms to further search and refine your design concepts and solve technical problems.  You will develop a much more sophisticated list of keywords than the ones above.  Sophisticated vocabulary, the jargon of the discipline (mechanical engineering, physics) will return articles geared toward that audience.  Use Google Scholar in addition to the databases.

Example vocabulary:

• kinetic/potential energy
• rotational/ transitional motions
• torsional springs / compressional springs
• pendulums / oscillating devices
• vibration
• escapement speed
• verge assembly / linkage
• cycle analysis
• stability analysis
• gear train ratios
• energy flow
• torque impulse
• time train / gear train
• oscillator
• frequency stability / frequency accuracy

Research Tip: 

The more specific your search terms (example: ampolletas (Spanish), clepsammia, clepsydra), the more focused your returns will be.  A few examples:

A Google Scholar search for clepsammia yields this Jstor article:
"The Operation of Sand Clocks and Their Medieval Development" from the peer reviewed journal Technology and Culture
Note - if you access from Google Scholar, click on the link in the RIGHT HAND COLUMN.

A Google Scholar search for mechanical engineering timekeeping yields this peer review article from Journal or Applied Mechanics
"The Mechanics of Spiral Springs and Its Application in  Timekeeping"
Access on campus - contact library@stxavier.org if you have a problem loading.  
Note - if you access from Google Scholar, click on the link in the RIGHT HAND COLUMN.

A Google Scholar search for engineer "sand clock" "water clock" returns an article from Notes and Records of the Royal Society of London (primary source) accessed through Jstor.
"Newton's Water Clocks and the Fluid Mechanics of Clepsydrae" 
Note - if you access from Google Scholar, click on the link in the RIGHT HAND COLUMN

A Google search for metrology time mechanical clock finds an article from the Naval Postgraduate School
"Precise Time and Time Interval Clocks, Time Frames and Frequency"

"Ten Crazy Clocks You Won't Believe Exist"
Source:  YouTube Tech Planet

Please contact library@stxavier.org if you find an article and need help accessing the full text. Send citation details.