Robotic Tracks / Treads

Tracks or treads, whatever you want to call them, are often the first thing that pop into many people's heads when someone mentions the word robot.  During my robotics course, I have run into a number of tread configurations, some better than others.  Below I have stolen a diagram that reveals a number of track configurations:

I have personally used methods A, E, and C.  The simple method (A) is relatively easy to configure but often requires re-gearing in order to drive the treads.  Most of the time the motor will not fit directly on the wheel since the treads are low to the ground.  In an attempt the correct the problem, I changed my robot to tread configuration E.  My mistake was I used the upper wheel to drive the treads.  Big mistake because in order to effectively drive the treads they should wrap close to 180 degrees around the wheel.  The upper wheel in configuration E wraps about 45 degrees and slips terribly.  In an effort to correct this problem, i changed to configuration C.  This has proven to be an effective design because it keeps tension in the treads and wraps the treads about 180 degrees around the drive wheel.  Below is a photo of my latest and greatest robot:

Happy roboting.

Essential Engineering Tools: A Video Blog

Just watch it and don't ask.

Evolution Wars: The New Global Warming Stunt

Just like global warming, the Evolution Wars represent another publicity stunt in an effort to obtain funding to research something.  Evolutionists strongly believe that life itself is a result of organisms evolving from one another as a result of Darwin's theory, survival of the fittest.  These new age Intelligent Design people on the other hand strongly believe there is no possible way life could have evolved on it's own and somewhere it received a 'little push' in the right direction from an intelligent designer (aka God).  Evolutionists can explain everything back to the Big Bang.  Their biggest flaw is they have no concrete idea where the bang came from.  A good Christian would proudly admit this bang came from God.

What I don't understand is these two things, evolution and intelligent design, can be considered the same thing.  That is to say, one could believe in both evolution and intelligent design.  Since atomic theory is still just a theory, we have no definite knowledge of the true design behind the atom and matter itself.  Did anyone stop to think that maybe, just maybe matter was design to 'evolve'.  Bonding is a natural phenomena that occurs in all matter.  If matter was all ready preprogramed to evolve, then both intelligent design and evolution occurs at the same time, and both parties are correct.  Just something to think about.

My Short Story

The moment that changed my life was the one knee inquiry I presented to my girlfriend of five years.  Moments before the big question, I tried to be somewhat of a gentleman and ask her father for permission.  His reply started with an "Oh no..." and ended with an "... I guess."

Bow-tying the ringbox with a bright red ribbon around my yellow lab's neck, I sent my furry friend into my girlfriend's grandparent's house, where her family gathers every Christmas morning like this one.  To my surprise, the mut actually made it through the house and to my girlfriend with the ring in one piece.  He then proceeded to meet my expectations when he violently shook the ring across the room the instant he arrived at her feet.  I'm still not sure why she said yes.

Actuators ex Libris: Hydraulic Power

Actuation and mechanical engineers go together like lamb and tuna fish.  Yet there are plenty of engineering schools that do not even touch the subject as it applies to the practical world, and above all else, how it applies to industry.  But man I am sure glad I learned to make that black box model.  The standard google search for designing actuation systems will leave you high and dry unless you use the right keywords which you conveniently don't know.  Lucky for whoever is reading this, my stumble-upon searches usually end up at some tech resource.

Enough crap, lets get to the good stuff.  Actuators are used to provide displacement in a mechanical system. The traditional actuator provides linear, or single axis displacement usually in the form of cylinder slides.  Actuation is provided primarily by electronic solenoids, pneumatics, and hydraulics. Gear systems (depending on how you look at it), can also be used but present an additional design element.  As general rule of thumb, system power and size increase in magnitude from:

electronic solenoids -> pneumatics -> hydraulics

Electronic solenoids and pneumatics generally provide forces up to the order of 100lbf, while most hydraulic actuators provide forces in excess of 10,000lbf.  

Actuators require a complete power system to function.  System design is the challenge engineers face, whether manufacturing the components or building the systems.  This article will address hydraulic power, but pneumatic systems are very similar operating on the same fluid principles and often using very similar components.  A basic actuation system is comprised of two main components: motive power and actuation.  The power in the system follows:

Motive Power -----> Transport Medium -----> Actuation

Electronic solenoids are simple, typically powered by a controlled AC/DC power source, the transport medium electrical wire connecting the components.  Pneumatic and hydraulic systems are slightly more complex, requiring a few more components.  The motive power is provided by a pump, and the transport medium consists of piping and valve controls.  It is worth noting a pump is comprised of two components: a motor and pump head (A topic to be discussed in a future article). A general hydraulic system is illustrated by:

Parker Hydraulics is a high end hydraulics manufacturer, and is also a great place to start for system components and information.

Self Evaluation Try Two

Well I did not really know where to start with myself so I took a look at my first Self Evaluation post and I have to say, I have definitely improved in all aspects of my blog.  I have doubled my blog content with relevant posts that reflect engineering tools.  I have increased my comments on other's blogs, but unfortunately have not received many comments on my blog that I can reply to.  My posts strive educate the reader about engineering tools and their uses.  I have incorporated many types of media into my blogs including hyperlinks, self-taken / create photos, and tutorial videos.

The Voltmeter

A voltage detector is essential tool to every handyman, craftsman, tradesman, and engineer.  The handyman and craftsman would use the small analog voltmeter in the bottom right to measure small time voltages every so often. The tradesman would use the voltage detector at the top in red to check high voltage levels from 120V to 600V.  The engineer would use the voltmeter, or more specifically digital multimeter (DMM) located at the bottom left in yellow, to measure circuit values.  Anyone and everyone should have the pencil voltage detector in yellow at the top right to detect the presence of electrical potential without any contact.  This little guy can and has saved many lives.

Today I will focus on the DMM, since it is widely used in engineering.  A good multimeter should be able to test AC/DC voltage, AC/DC current, resistance, continuity, diodes, and capacitance.  Some meters may also feature transistor testing, a nice feature.  A good multimeter should cost around $100-$150 and should have a replaceable fuse (try and get a few spares because if you mess up measuring current you will for sure blow a fuse).  The video below teaches the basics of electronics components and taking measurements with a DMM.