Four-bar linkage analysis

Four-bar linkage analysis: 4R quadrilateral

The four-bar linkage is a basic machine component. It comes in two primary forms the 4R quadridlateral and the slider-crank. Here are my notes for the analysis of the 4R quadrilateral.
http://synthetica.eng.uci.edu/mechanicaldesign101/McCarthyNotes-2.pdf

Four-bar linkage analysis

Four-bar linkage analysis

Motor Torque and Power

DC motor torque and power

A copy of my notes on DC motor torque and power can be downloaded at the link:
http://synthetica.eng.uci.edu/mechanicaldesign101/McCarthyNotes-1.pdf

Motor Torque and Power

Motor Torque and Power

Phyclips from UNSW

DC motor basics

The basic principles of DC motors are presented by Joe Wolfe of the University of New South Wales (Sydney, Australia) at the link:
http://www.animations.physics.unsw.edu.au/jw/electricmotors.html

Phyclips from UNSW

Phyclips from UNSW

Northwestern University (Chicago, Illinois) presents the basics of a DC motor in the Wiki page:
http://hades.mech.northwestern.edu/index.php/Brushed_DC_Motor_Theory

Northwestern University Wiki page

Northwestern University Wiki page

MatWeb:  Material Property Data

Mechanical Properties of Steel

The MatWeb site provides detailed information about materials such as the tensile strength of various compositions of steel.

MatWeb:  Material Property Data

MatWeb: Material Property Data

For example the search “low carbon steel” results in the list of links to information:
http://www.matweb.com/search/QuickText.aspx?SearchText=low%20carbon%20steel

Total Materia

Unified Numbering System for Materials

There are a variety of numbering systems for materials such as steel. The unified numbering system (UNS) uses a letter to designate a material category followed by five numbers constructed from the existing materials designations to coordinate all of these numbering systems.

The unified numbering system (UNS) is described in Wikipedia at the link: Unified numbering system

Some of the category letters for steel are:
– G for AISI/SAE carbon and alloy steels;
– S for stainless steels; and
– T for tool steels.

Generally, the standard designation is inserted after the letter defining the material category. For example, AISI/SAE 1018 carbon steel has the UNS designation G10180.

The AISI-SAE steel alloy designation system is listed in Total Materia.
Also see Wikipedia at the link:  SAE steel grades

Koenigsegg Door

Koenigsegg door system

The doors of the Koenigsegg CCX open using the “dihedral synchro-helix door actuation” system. You can see this movement on the video

Elastic Modulus v. Density

Material Properties Charts

Cambridge University provides a useful overview of materials properties such as the chart below.

Elastic Modulus v. Density

Elastic Modulus v. Density

The tutorial can be accessed at the link:
http://www-g.eng.cam.ac.uk/125/now/mfs/tutorial/non_IE/charts.html

Jansen and Klann Legs

Comparison of Klann and Jansen leg linkages

Joseph Klann provides a useful comparison of the leg designs for his Mondo Spider and Theo Jansen’s Strandbeest at the link: http://www.mechanicalspider.com/comparison.html

This link may be unreliable so here is an interesting article comparing the leg designs:  Mechanical Spider Using Klann Mechanism

This is a youtube video prepared by William Thielicke that illustrates the two leg mechanisms.

Mondo Spider

Mondo Spider walking machine

This walking machine known as the Mondo Spider.

 The leg of the mondo spider has the topology known as a Stephenson six-bar and is described in US Patent 6,260,862 awarded to Joseph Klann. Access it through the link:
http://www.google.com/patents/about?id=70YHAAAAEBAJ&dq=6,260,862

Wikipedia calls this the Klann linkage described here:
http://en.wikipedia.org/wiki/Klann_Linkage

 

Jansen Strandbeest

Theo Jansen’s walking machine

Theo Jansen builds amazing walking machines.
Each leg is an eight-bar linkage. The Wolfram Demonstration Project models this linkage in a Mathematica notebook. See the link:

http://demonstrations.wolfram.com/ATheoJansenWalkingLinkage/