Saturday, February 25, 2017

Advanced Engineering: Grove Model Complete!

If you've been following this blog, you might recall that the Advanced Engineering class was laying out conceptual designs for a playground structure destined for the Lower Campus. They have been fairly quiet since then, except for announcing a grant that was awarded in October. However, much has gone on in the background: our six students have been learning about stress strain, Hooke's Law, materials science, and cross-section analysis. They also began work on a long-term design report that will be completed by the end of the year.

And then...

Our own Sarah Jane suggested that the group take the advice of local architect Jeff Shelton, and turn out a scale model of our intended structure. It wasn't in Mr. Meadth's original curriculum plans, but it seemed like a good idea!

So they turned to the CAD model.


For any CAD nerds out there, you'll recognize this as having been created in SketchUp, a fully-featured free program commonly used by architects and product designers the world over.


This model was completed jointly by the entire class, with each of the six tackling individual parts and then sending the file to Mr. Meadth for incorporation into the whole.


Some aspects of the model have been since changed, such as standardizing the railing system across the entire model. It's a continual work in progress, as the group shifts from conceptual to detailed design.

After some packs of balsa wood, modelling clay, and other miscellaneous items arrived in the mail, the team set to work making a 1:16 scale model. Caleb became quite proficient with a craft knife.


The four surrounding trees were created in clay, courtesy of Sarah Jane, and Kylie got very good at staining balsa with a foam brush.


Hot glue guns at the ready!


Jake carefully placed his pieces onto the board (helpfully supplied by Tys)...

Much work was done by Aaron and Kylie over the next few weeks, in lieu of their usual teacher assistant job in Foundations of Engineering II, and our Westmont engineering intern, Robert Huff, also lent a hand at the very end. A few 3D-printed black tires and a whole lot of sawdust completed the scene, and the designers gathered to celebrate!






Finally, the completed model was transported to Lower Campus, and descriptive labels were attached so as to describe some of the features to passers-by. Mr. Knoles proudly placed the entire scene with some CAD images right by the front door of the office, and it only took a few moments for a small crowd to gather and start asking questions!



Bottom line: the project is alive and well, and please stop by the Lower Campus to view the completed scene. We have another grant in the works, and already have some parents who have offered to help with donations and construction (commencing in May and continuing through the summer), but please reach out and contact Mr. Knoles (mknoles@providencesb.org) or Mr. Meadth (rmeadth@providencesb.org) if you would like to offer skilled help/resources, or know someone who can.

And don't forget to cheer on our engineering students when you see them!

Tuesday, February 7, 2017

Robo Puppies

Meet Astro and Cookie--they don't eat much and they won't mess up your house. They will, however, bark and sit and nod their heads, and maybe even roll over!

The star attractions at our table; note the colored "bone" used to give commands
to the two puppies

Last Friday, Astro and Cookie--and their human handlers of course--were invited to come play with the elementary students at El Montecito School, as part of their Techsploration Day. Twelve groups of ELMO students came to visit the robot puppies one by one, and everyone saw just how easy it is to write code and have fun!

Four of our high school engineering students (Jake, Caleb, Tys, and Sarah Jane) guided the El Montecito students through a ten-minute crash course in robot programming. Our students asked the younger ones what they wanted each puppy to do...

Sit up?

Bark?

Nod its head?

Blink its eyes?

Say what color was in front of it?

Roar like a T-Rex?

Jake and Caleb show the younger students how Astro receives his coded instructions

After writing in this command, the students then included some sort of trigger in the code, again asking the younger ones what that trigger should be...

Show the puppy a specific color?

Pat it on the back?

Press the buttons on the front?

Sarah Jane explains the finer points of Cookie's
inner workings

In just a few minutes, the older students were able to write the program described, all shown in full color as it was being done. It downloaded instantly via Bluetooth, and the students could see the outcome. Astro ran on the spot, and Cookie nodded approvingly. Astro sat up when he saw red, and Cookie showed off by naming any of four colors shown to her.

This simple code 1) waits for the color green to be shown to the sensor, 2) plays
the sound file "Dog bark 1", and 3) runs the motor to raise the head

Sarah Jane, Jake, Caleb, Tys, and Mr. Meadth (rear)
Astro and Cookie (front)

Many thanks to Tim Loomer, Colette Crafton, and all the staff at El Montecito for receiving us, and running a highly successful Techsploration Day. The rain couldn't dampen anyone's spirits, and it was a delight to see the meaningful collaboration between the two Christian schools.

Saturday, February 4, 2017

Middle School: A Mechanical Advantage

The second semester of the middle school elective, Intro to Engineering, takes on a special theme each year, and is intended for 7th and 8th Graders who are repeating the class. Last year, the theme was space exploration, and the theme was matched with our first annual Science & Engineering Expo, which was a huge success.

This year, the second semester theme is "Machines", with a focus on the simple machine types described by Renaissance scientists. We have looked at the history of modern and pre-modern humanity in this area, wrapped around such figures as Leonardo da Vinci, Archimedes, and Vitruvius (not the LEGO wizard--sorry!). As well as the artistry and ingenuity, we're also studying the idea of the physical concept of work, and how energy is conserved and transmitted in mechanical systems.

One of the simple machines that was studied in antiquity was the pulley--a rope wrapped around a wheel to change the direction of force. The compound pulley is even more interesting, and allows us to dramatically increase our "mechanical advantage". In everyday terms, this means that we can make ourselves stronger. But to talk about it is not enough: you have to prove this kind of thing outside!

Using Mr. Gill's outdoor education equipment and some 400 lb pulleys from Ace Hardware, the students themselves arranged the constituent pieces, hanging from the sturdy structure of the outdoor basketball hoop (not the hoop itself). On the previous day, they had worked with small model version indoors, so they knew how to set things up. It didn't hurt to have some Boy Scouts in the group, too!

Students working out how to set up the equipment

With everything secure and checked, and a safety mat below, the first student was hoisted up into the air.

Julian was our first contestant!

Pedro gets a taste of the air up there

Josh holds on as Pedro slam dunks!

Our particular compound pulley system had two wheels where the hanging student was located. This means that there are four lengths of rope leading away from the load. This gives a mechanical advantage of four, which means that, aside from friction losses, the person pulling is made four times as strong! If a 100 lb student hangs from the pulley, the person pulling only feels 25 lb.

Two wheels at top and two at bottom; the lower pulley moves up with the load,
while the upper pulley stays in a fixed position; note Sam's bowline knot!

Other notable moments possibly occurred as well...

Chloe representing for the girls!

Tommy and Julian being lifted together at once

Mr. Meadth showing a great deal of trust in Sam

Success!

Payback time for Chloe and Belen

More news coming up later this semester, and keep an eye out for this semester's Science & Engineering Expo in April!

Friday, January 20, 2017

Guest Speakers: Patrick Lindsey and John Horton

Last Tuesday, our Foundations of Engineering II class had the privilege of hearing from chief mechanical engineer, John Horton, team manager and driver, Patrick Lindsey, and Lindsay Lindsey, Patrick's wife, of Park Place Motorsports. Park Place Motorsports is a professional racing team that competes in WeatherTech, a branch of NASCAR devoted to racing sports cars.

John Horton stressing the importance of teamwork in racing.

Mr. Horton recounted his journey to a profession in the racing industry from his childhood fascination with his Erector metal construction sets to a life-changing auto shop program that he joined in high school. He stressed the importance of cooperation when working as an engineer, particularly in a field such as professional racing which combines a multitude of engineering disciplines.  On the matter of cooperation Mr. Horton said, "There's always something that you don't know about that you need a network to help you solve. Communication is key."


Patrick Lindsey explains the art of cornering in a race car.

Mr. Lindsey focused on the driving aspect of the race, showing data gathered from tire sensors during a lap at Daytona Speedway. He related the shape of the graph at a particular instant to what the car was physically doing at that point and talked about the importance of such graphs in making sure that the car was operating at absolute peak performance.

Our guests were also able to relate their profession to our recently (almost!) completed project: the robotic self-driving car. Jakob explained the various elements of his team's robot to Mr. Horton, such as the drive motor system and the rack-and-pinion steering, and Mr. Horton confirmed that the same features were present on their Porsche, just scaled-up and more advanced.

The Foundations of Engineering II class with their guest speakers.

The Park Place Motorsports Team ended their presentation with an inside-the-car video of a lap around Daytona Speedway and a directive to pursue their passion for science and engineering to wherever it may take them.

We are thankful for the visit from the Park Place Motorsports Team, and wish them luck in their upcoming 24-hour race at Daytona Speedway!

Wednesday, December 21, 2016

Project: The Self-Driving Car

We've recently reported on the Advanced Engineering I playground design project, but what exactly is keeping the younger group busy right now? If you pass by Room 401 most any afternoon, you'll find twelve freshmen and sophomores, six computers, three VEX robotics sets, two T.A.s, and one teacher very hard at work! The project? It's a little ambitious, but we are intending to design, build, and program three self-driving robot cars, in the manner of Google, Uber, Tesla, and a few others.

Just another typical day of class in the Providence Engineering Academy

The way of the future! But first a bit of background. Robotic cars fall into two broad categories: smart cars and smart roads. Smart car systems have all of the design and engineering and intelligence in the car itself, relying on GPS, lots of sensors, and careful programming. By contrast, smart road systems have some sort of marker built into the road itself to provide information to the car--one idea proposed in the past was to have magnets embedded into the road surface. While all companies are now putting all of their efforts into the "smart car" option, ours fall into the "smart road" category; we have a white line track on a dark background that shows the car where it needs to go. No white line means no navigation.

Left: the design brief and the plans for the roadway; right: the actual roadway,
newly constructed, mounted on an 8 foot by 8 foot plywood base

So what does it take to get this going? The number one resource is human intelligence; each of the three teams comprises four students, with distinct roles as follows:
  • Team Leader: co-ordinate efforts, give attention wherever needed, be an all-around expert in everything, and keep a daily Captain's Log.
  • Mechanical Engineer: primarily responsible for building the physical structure of the robot, mounting sensors, and attaching custom parts.
  • Programmer: working on code that will navigate the robot around the course.
  • CAD Specialist: design custom parts in a CAD program, and then print them out for use in actuality.
The beauty of this is that each member necessarily must work together with the others to achieve the outcome. The mechanical engineer needs input from the programmer as to where to place the sensors so that they work with the written code. The CAD specialist needs to also work with the mechanical engineer to decide what is most needed and where it should be placed. The team leader needs to choose just how to spread themselves each day to get the current priorities in order.

Ben (left) working on code; David (center) attaching his wheels to the frame

Samy, one of the mechanical engineers, putting together a frame for his
team's vehicle

Each team was allowed to choose between two types of steering design: rack and pinion, or a simpler design where the entire wheel and axle rotates around a central pivot. All three teams went for the rack and pinion, which is the same design found on modern cars. A single gear (the "pinion") rotates on a flat linear gear (the "rack"), which pushes it left or right, in turn causing the front wheels to point in either direction.

The custom CAD parts are another particularly exciting part of this project: the three CAD specialists are using the online platform Onshape to make pieces that are specific to their own robot. Just for fun, one team created a license plate with their team name, which is now proudly mounted on the front. Two teams are currently working on a box to hold a payload to be delivered along the route. The third team created a "shadow shield" to go underneath the vehicle and keep the line-sensing infrared sensors out of direct sunlight to make them more effective. The CAD specialists had to create bolt holes that match with the VEX robotics system, and they have infinite control over everything else.

One team's container design, intended to hold a small payload; a door is going
to be added to keep things secure until delivery

Another team's payload device is an open tray which flips up to release
upon command; note the square axle hole for connection to the motor

Both of the above designs are printed full size; so far, it looks like they will
be perfect!

The teams have another couple of weeks to finish this project, and they look to be on schedule for completion and demonstration.

Mr Meadth also decided that it would be fair for him to produce a proof of concept--can this really be done, after all? He used one of the spare middle school LEGO sets, which has an array of similar sensors and mechanical capability, but a very different coding language.

LEGO Mindstorms coding language--colourful blocks that snap together!

RobotC coding language, as used by the high school students--lines
and lines of colour-coded text

After a few hours of work, he came up with this smaller LEGO version, and it gets around the full track in about 18 seconds on its slowest, most cautious speed.

The LEGO robot car in action--note the three colour sensors in a bank on the
front; having three side-by-side allows for more sensitivity in response to the
car's exact position



Proof positive--it can be done! Upon completion, the robots will be demonstrated to the Providence community; we may go down to Lower Campus and show one of the elementary grades what we've done. Stay tuned.

Friday, December 9, 2016

Visit to UCSB Mechanical Engineering Department

On Monday of this week, sixteen Providence teachers and students took a trip out to UCSB, to visit the Mechanical Engineering department. Kirk Fields, Senior Development Engineer, met the group there and gave a tour of a few of the lab spaces.

The "clean room" was the first stop, and we noted that this is where Sarah Jane's father works to assemble his company's tiny lasers. We didn't see him through the window, but there were many interesting microscopic images of gecko feet!

The materials testing lab tied in well to what we have recently studied with our older group, Advanced Engineering I. Our students have been testing various materials in compression, carefully measuring the loads required to produce deflection, and deducing the modulus of elasticity--in layman's terms, a measure of how "springy" a substance is. This UCSB lab held dozens of industrial-grade machines to do similar experiments in compression, tension, fatigue, and so on.

Kirk (right) shows us the materials testing lab

Kirk was also able to show us a special research project, which involved a Perspex beam that "pushes back" when it a load is applied. Ordinarily, pushing on a beam would make it bend downwards, but this beam is equipped with sensors and motors that resist the action; this creates a beam with "infinite stiffness", so to speak.


The beam of "infinite stiffness" reacts and pushes back against applied load

We walked through some other spaces (including the wind tunnel), ending up in a robotics lab that housed an in-house competition much like what we do in our own middle school and high school classes. The college students design robots using a variety of motors, sensors, and LEGO structures; the robots ("rats") run around a walled-in elevated platform and collect "cheese".

One of the "rats" from last year is on display in the central case

The visit, though short, was well worthwhile. Jake, our senior, recently applied to this college and this department, so he was glad to meet some people and get a firsthand look. Mr Hurt, also present, graduated from this campus, and happily reminisced about times past.

All in all, a positive experience, and we're grateful to UCSB and Kirk Fields for allowing us the chance to come by!

Tuesday, December 6, 2016

Upcoming Event: MS Final Challenge!

In the Providence Middle School, fourteen 7th and 8th Graders are working busily on their capstone project for the semester: the Intro to Engineering Final Challenge! Every semester, the students in this elective are given a game-style challenge to complete, which involves designing, building, and programming a robot using LEGO Mindstorms EV3 sets.

This semester's challenge is being played out on a large elevated plywood platform, 8 ft by 8 ft. Mr Meadth spent a happy few hours putting this together in the science lab.


Each team of two students must create a robot that can sweep the platform clear of various pieces of coloured "debris"; imagine a small robot whose task is to permanently keep a rooftop helipad clear of windblown trash. Two robots are running in each round simultaneously, and whoever pushes off the most debris wins.


Special note: the pieces of "debris" we are using are the game pieces designed by Eva last year for her high school Educational Design project! Naturally, they are printed on our mod-T printers, which are still running strong (and now only $299 on their website!).

There are significant challenges associated with this project. How do you keep the robot from falling off the edge of the platform? How do you actually have the robot find the scattered debris? Does it run a blind search pattern, or does it try to use sensors to actively search? What kind of locomotive means does it use? Tracks or wheels or something else? What if it bumps into another robot?

Let's introduce our competitors this semester:

Isabela and Lily with their wheeled wonder--note the absence of rubber tires
on the front wheels to allow sideways slippage when turning

Christine and Sofi with their light and fast Pretzel Bot

James and Dylan with an imposing bulldozer--note the ultrasonic sensor on the
front to look for debris

Zach and Alan also went with a tracked design, and a large superstructure on
top for style points!

Ma.kaha and Cameron put their colour sensor way out in front to detect the edge
of the table--not falling off the table is critical to success!

Asher and Sam have an armoured design that looks just plain scary

Masato and Isaiah did some late redesign work to try to bring down their weight--
the robot with a lower weight gets the advantage of being placed first

The students will be presenting their completed designs to the rest of the class this Friday. The actual competition will take place in the Boys & Girls Club gymnasium on Monday and Tuesday at 1:00 during regular class time. Parents and friends are welcome, and it promises to be a lot of high energy fun!