Archive for the ‘Engineering’ Category
I did this engineering challenge last year, but it didn’t go the way I wanted it to. I provided the kids with a stick, about 25″ long as the basis of a reach device. My mistake was allowing them to split the stick in half. As a result, they all made a big scissor and then made some small modification to make it grip.
This year, I have added a whole new level to the challenge. The stick can not be cut, only drilled for brass fasteners. They are given a budget and each item has a cost. I made sure they can only purchase a single stick with their budget. Purchasing two of them will put them immediately over budget and cost them lots of points.
The challenge came from pbs.org/designsquad, they have a few things there worth looking at if you are into engineering challenges. I downloaded the information a while ago. Here is the link for the activity: http://pbskids.org/designsquad/parentseducators/resources/helping_hand.html
Here is how I modified the activity for use in my classroom: Helping Hand Challenge. If you use this, let me know what you add or change. I will be using this tomorrow. The scoring rubric is at the bottom.
Update: I’m still angry over how some of the kids approached this. A couple of the really lazy ones did nothing but complain for two days. At the last second, they purchased a foot of tape, wrapped it around the stick and then tried picking up the objects with the sticky tape. Naturally, I changed the rules so that can’t happen next year. Tape got very expensive. I also changed the grading to downplay the points earned for moving the object and increasing points for the design. Essentially, I changed the grading to reflect effort and creativity. With the change in focus, I will need to watch for students copying ideas.
I’m not one to reblog. Once in a while I get an email asking me to post something. I usually ignore the request or politely tell them, “No thanks.”
This is from one of those spamish emails I get. I have searched the site and it links mostly to University of Phoenix. Regardless, ignore the rest of the site if it bothers you, but the article is worth your time. It’s called the “25 Female STEM Superheroes of Today”, here is the link: (http://www.onlineuniversities.com/blog/2012/06/25-female-stem-superheroes-today/).”
I know if you asked me to list influential female scientists and engineers, I’d be very hard pressed to name five, let alone twenty-five. It’s kind of a shame, but it’s nice to know someone is keeping score.
#3 – Ribbon Climb
#2 – Battle Bots
and #1 – Inventorying the kits for next year.
Sorry for the trick, but we started trying to put the kits back in order. Most weren’t done after a full hour. All the groups have both a standard kit and a blue resource kit. They were under orders not to borrow or loan to other groups. That didn’t happen. I needed the basic kits back in shape so the students next year can build the basic robot that we use for the first couple of months. The kits are a complete mess.
One trick I came up with from my manufacturing days… I made photocopies of the groups of parts. The student place the identical parts on their picture. When the sheet is full, they deposit that sheet’s parts into the assigned storage location. So simple a child can do it, or hopefully a high school senior.
On to the ribbon climb. This was a variation of the rope climb, but the kids liked it a lot more. The ribbon was a 7 foot-high, 3 inch-wide strip of manila folder that was covered on all sides with duct tape. The folder gave it rigidity so that it could stay within edge guides. The tape gave us protection from massive paper cuts and also provided a higher friction surface.
I educated the kids on the use of gears and mechanical advantage. Some of them listened and their robots carried between 0.5 and 1.5 kg of additional weight up a ribbon.
The actual last challenge was Battle Bots. The rules quickly morphed into the following, and it was a major hit.
- Teams can battle every robot once a day for points. I had to witness the point battles for it to count. Teams can battle as often as they want, just not for points.
- Robots can only be built with the parts in their two kits. No outside materials are allowed.
- You win by flipping your opponent’s robot over or pushing it out of the arena. (Nobody got pushed out, the wall were too high – there will be lower walls next year.)
- The battle goes one minute. If at the end of a minute, there is no winner, both teams get one point. If there is a winner, the winner gets 3 points, the loser gets 1 point.
- You win by accumulating the most points over the period of 5 days.
In the last couple of weeks we’ve done some new LEGO Robot Challenges and I’m really pleased at how they turned out.
First was my LEGO version of the Hungry Hippo game. The students were tasked with creating a robot that drives around gathering balls and marbles. The robot that collects the most points worth of marbles and balls in 60 seconds wins the challenge. The balls are the colored balls that are included in the robot kits. The large balls are worth 5 points each, the marbles are worth 2 points. Students had to come up with a strategy and then build to that strategy. The best design drove around with a scoop on the front that shoveled the captured balls into a bin on top. Many designs had rotating claws in front to direct the balls into a pen.
About a week into the challenge, students were tasked with doing a design review with another group. They had to critique the other groups’ project and suggest ways to improve the design, then have the same done for their project. All of the groups felt they got something out of the design review process.
The arena was our own Octagon I created out of 1×4’s. Each side of the octagon was 24″ and the sides were held together with masking tape. It was sturdy enough that the robots could bump into the walls and trigger a touch sensor. The plan was to have the robots go head to head in the arena, but they all locked up so badly that each robot did individual one minute runs.
The latest challenge was a rope climb. I first showed the kids a couple short videos on the space elevator and we had a short discussion on the cost benefits of such a system. They were given a short week (4 days) to design a robot that could climb up a rope. I hadn’t tried this before so I didn’t know what to expect. I had a few robots climbing the rope within 30 minutes, so I had to up the ante. Basically, they got a C if the robot climbed the rope. If the climber carried a 0.5 kg weight up the rope, the group got a B. If the robot managed to carry a full kilogram weight up the length of the rope, the students earned the A. Only one group managed the A using an innovative design of tires and belts.
I’m going to challenge them to go back to the drawing board on this one and see who can carry the most weight up the rope. After that, we are going to do Robot Wars in the Octagon. The goal is to disable your opponent or remove them from the ring. It should be fun.
If you are not familiar with TED Talks, you need to come out of your cave. I have a problem with these videos. I can’t stop watching them. Life got busy and I guess I forgot about filling my brain with a little bit of inspiration. I was recently reminded of the TED Talks by Kaitlyn. She sent me a link to her blog with 15 physics talks. You can find her blog post here: http://www.onlineuniversities.com/15-fascinating-ted-talks-for-physics-students/.
When you are there, make sure you take a look at this talk by Dean Kamen. I’m showing it to my engineering and robotics students tomorrow. My hope is they see the importance of what they are doing.
My two robotics classes have been working on an obstacle course. I made it challenging, but it seems to be too challenging – not because the kids aren’t trying but because the robots do something a little different every time. I’m confused. I called LEGO Education support and they told me the motors are accurate to one degree per rotation.
I’m seeing errors much more than ten times that number. I can’t seem to find a way to solve the problem. We are using yellow RESET block, light green MOVE blocks, and orange rotational WAIT blocks. We have a spot carefully marked on the floor for the start and way points. Starting at the same spot may have the robot as much as an inch off within about 10 rotations. The total motor error should be about 0.17 inches. I can’t determine if it’s a problem in NXT-G or the motors.
I’ve searched the NXT books, blogs, web sites, and books, and I can’t find any references to the inaccuracy issues. Has anyone else seen these problems? How do I fix this?
Last year, the course was actually called Robotics and Astronomy, or Robostronomy for short. The intent was half-year of each. The result was more like three weeks of astronomy and robotics all year-long. Don’t get me wrong, I love astronomy. It’s just, well, Robots took over the Earth. Between the great things we could do with the MindStorm, and then the SeaPerch competition, we were all robots, all the time. This year we are adding the First Tech Challenge. Yep, Robots have taken over the Earth, and it looks like they landed in my classroom.
The goal here is STEM, that’s what opened the door for the robot invasion in the first place. Clearly missing from our program these days is what we called in the old days, ‘drafting.’ Drafting isn’t done on a board with a T-square anymore, but you all know that. Today, 3D mechanical Computer Aided Design (CAD) is available for free from Google (Sketch-up), and from a number of companies who cater to the high-end. I actually know this industry well, I spent 25 years in the CAD/CAM/CAE industry (M for manufacturing, E for Engineering, meaning simulation).
So with some guidance from some friends at Drexel University, and a little research on my own, I decide to go with SolidWorks software. All of the vendors have aggressively priced programs for the educational market, I think we are paying just $1000 for a 10-seat license. What makes this software connect to the students is what we spit out of it. The school invested in a 3D printer, specifically uPrint Plus from Dimension.
If you have never seen one of these, think Star Trek Replicator. The replicator creates parts from ABS+ plastic directly from the output of the 3D CAD. How better to teach engineering principles than to give the students a design challenge, have them work through designs and then fabricate it in the printer. Here is a great video from a customer talking about how they use a 3D printer in their engineering design work.
My new printer is due here any day and I’m pumped up. Yep, geek boy has a new toy. Tea, Earl Grey, Hot!