Friday, October 23, 2009

SA BEST Game Day is Saturday, October 24

Today, SA BEST volunteers will tear down the game field and move it to the main auditorium in the Greehey Convocation Center. During the past week, the game field has been installed on one of the basketball courts in the Auxiliary Gym at Greehey. Our intent was that the field would be available for teams to practice with their robots. This afternoon, we will move the field and set up all of the support areas (pit, display, check-in, etc.). The last of the oral presentations will be given this afternoon and evening.

Tomorrow, Game Day, we will perform final checkout of the field and all support, and finish checking in teams at 10 AM. That's the signal for the chaos to begin. If you're coming, you might want to bring some earplugs, because it can get noisy in the gym.

Thursday, October 22, 2009

RFG final meeting

Yesterday, October 21, was the final meeting of this fall's Robotics for Grandparents class at ALIR.

I must apologize for my poor presentation of the material and the lab for Lesson 6. Although I was able to get the robots to communicate at home, they would not link up properly at ALIR, and so the lab was useless.

I did, however, have some video material on space program robotics, and was able to show several short video clips. The clips showed a variety of activities, including one with an astronaut riding on a workstand at the end of the Space Station RMS. Another clip showed the SRMS and SSRMS handing off and berthing the OBSS (alphabet soup!). SRMS is the Shuttle Remote Manipulator System; SSRMS is the Space Station RMS; OBSS is the Orbiter Boom Sensor System, an extension that carries cameras and other instruments for detailed tile inspection.

Toward the end of the class, our invited speaker, Mike Henry, arrived. Mike shared his enthusiasm for youth robotics, as well as a comprehensive coverage of the various programs for youth robotics in San Antonio. His brief talk was very well received, and I think he may have inspired a couple of new volunteers!

Just a reminder: On Saturday, starting about 10 AM, San Antonio BEST Robotics will hold its 2009 competition, entitled "High Octane". The game theme involves robots of the future operating a fuel refinery. The competition is held at St. Mary's University, in the Greehy Convocation Center. It's a free public event, so please come and cheer on your local team: home school, high school, or middle school. There are 29 teams competing this year, some from as far away as Laredo. I'll be there, and I hope you will, too.

Finally: It has been great fun teaching Robotics for Grandparents this year. I plan to return and teach it in Fall 2009. In the meantime, there are rumors that there could be a similar course for seniors taught as a continuing education course in the Spring. I hope that my students enjoyed Robotics for Grandparents as much as I did!

Tuesday, October 20, 2009

Tomorrow is the last class meeting for Robotics for Grandparents 2009

Due to time pressure from other activities (over-volunteering), I have had to reduce the scope of the lab for tomorrow's class.

My original intent was to write software for three robots that would establish one as the dance leader and the others as followers.  That's not going to happen - not right now, anyway.

The lab for this time will be to connect the three robots together with very simple programs.  One bot will wait for a button press, then send a message to the other two bots.  The other bots will wait for the message to arrive over Bluetooth, and will take some action (making a sound, moving, or other).

The NXT line dancers will have to wait for another day.

Monday, October 19, 2009

Demonstration Day at SA BEST

Sunday was the Demonstration Day for the teams in the SA BEST competition for 2009. Each team had to bring something that looked like a robot, even though incomplete, and an "Engineering Notebook" that described their concept and their work so far, as well as their methods. I'm going over the notebooks now, as one of the judges. They vary in quality, as would be expected. I have to have my review complete by noon today, so I can pass them back to the "Head Judge", Tom Deeter.

Friday, October 16, 2009

Encino Park Robo Club

At today's meeting of the Encino Park Robotics Club, I presented the kids with the same material I used for Wednesday's Robotics for Grandparents.
I had a small group - about a third of the club - and they picked up very quickly on the line-following technique and the details of the light sensor. I heard some interesting questions, and we answered many of the questions by trying experiments with the robot. We didn't get through all of the kids, so one of the teachers or another volunteer will use my Powerpoint slides and the line-following robot at next Friday's meeting. I invited the kids to come to the SA BEST competition on Saturday, October 24th.

Wednesday, October 14, 2009

RFG Week 6 (The Final Episode!)

Next week's lesson will cover Bluetooth communication among a set of NXT robots with almost identical programming.  One robot will command the others to move in sync (sorry, no music), and will do the same motions itself.

As a bonus, we will have a guest speaker, Mr. Mike Henry, who will discuss the several youth robotics programs that can be found in the San Antonio area.

Note to interested parties: San Antonio BEST Robotics is in the middle of a robotics competition.  The "Demo Day" will be held Sunday, October 18, in the Convocation Center at St. Mary's University on Culebra Road.  Game Day will be held in the same location on Saturday, October 24.  Details are available at the SA BEST web site,

Week 5 of Robotics for Grandparents

Today the class tried calibrating a light sensor and following a black line on the test track. The results were good, and there was some interesting discussion about how line-following programs and devices work (and sometimes don't). A simple line-follower such as we were using can easily get lost and can't easily recover (its search for the edge is very simple).

On Friday, I'll show the line-following technique to the Encino Park Robotics Club. It should be fun to compare the 5th-graders' reaction to that of the grandparents!

Monday, October 12, 2009

Robots for RFG Week 5

The three class robots are built and tested, and ready to go to work! Instead of a third-wheel caster, the design uses inverted "claws" as skids on the front. The skids press the paper down (if on the paper test track) as the robot goes over it. The robot can go astray - losing track of where the line is - and sometimes it will recover and get back on the line. Other times it will loop around aimlessly.  In the class lab, we will use a version of the program that's split into two parts: a Calibrate program and a Follow program.

Wednesday, October 7, 2009

Week 5 Class

For Week 5 of Robotics for Grandparents, we will work with a new robot design that will follow a black line around the practice mat.  This will involve the use two programs: one to "train" the light sensor using calibration, and another to run the course following the line.  This design and program are from the web site

RFG Class 4 - Ultrasonic Sensor and Display

Today's class covered a lot of ground in a short time. The lab problem involved the use of the Ultrasonic Sensor, the Rotation Sensor, the Touch Sensor, the LCD Display, "wires" to move data around, data conversion, and the "NXT Buttons" sensor. The objective was for the robot to wait until an object came within 12 inches (at the front), then move until touching the object, and display the distance moved (in degrees of wheel rotation). All three teams were able to complete the problem.

Sunday, October 4, 2009

RFG Week 4

In Wednesday's class, we will cover three sensors, the display, and signal wires

  • Sensors
    • Ultrasonic sensor
    • Touch Sensor
    • Rotation sensor (the servo motor as a sensor)
  • LCD Display
    • Displaying text
    • Displaying a number
  • Signal wires
  • Number to Text conversion

Saturday, October 3, 2009

EP Robo Club Meeting Friday

The Encino Park Elementary Robotics Club met again on Friday, October 2nd.  At this meeting, the teams were given challenges based on their readiness.  Those who were making the most progress were assigned a board challenge, in which they had to push an object to a point without going too far, then turn.  It was interesting to see how everyone attacked that problem.  Ms. Craig demonstrated how to use the motor's Rotation Sensor to find out how many rotations would go 12 inches.  I suggested that in this exercise the students use a pointer (like an axle) pointed toward the surface to precisely index the starting and ending locations. 

More on labeling

The Brother TZ tape doesn't stick as well as I thought. Next try is to wrap the TZ tape with some clear 3M tape.

MG Mathscript

I got a good, clear answer from the forum on how to import a block to the NXT development environment. I now have the MG mathscript block in the Advanced group of the Complete palette. The key steps are:

1. You must have the block import/export wizard installed. It's a download available from the same place as new firmware versions.
2. Start the NXT application.
3. Open any program (it can be a new one like untitled-1) for editing.
4. From the menu, select Edit, then Block Import and Export Wizard. This will open a dialog that tells what to do next.
5. From the dialog, click Browse, and locate the folder with the block to be imported. You should now see the name of the desired block.
6. Select the desired block, and select a palette
7. Click the Import button, and you're done.

Thursday, October 1, 2009

Custom blocks from the Web

I found a very cool custom block called MathScript on the web site.  It actually does high-level math by operating on text scripts. 

I've downloaded it to one laptop, and I think I put it in the right location, but the NXT development application can't find it.  There is a patch available to add the import/export block capability, but even after applying the patch, I can't get it to work.  A question to the forum may bring me an answer.

Labeling stuff

I'm working with 3 or 4 Mindstorms NXT kits at a time, so the parts can get mixed around occasionally.

Because the NXT sensor/motor cables are all black, they're somewhat difficult to tell apart, and it's important at the end of the day for each kit to have the right assortment of cables: 2 of the 50cm cables, 4 of the 35cm cables, and 1 of the 20cm cable.

The way I can tell what goes where is to make two labels for each cable: one with the kit ID and another with the cable length on it.  So each cable is labeled "TPO1" and "50cm", for example.  Both labels are at the same end, for ease in sorting them. 

I used Brother TZ tape, 3/4 inches wide, red on white, with large lettering.  This tape wraps around the wire and sticks very well to itself.

A similar scheme will work to keep the USB cables from straying.  It might be useful to label the sensors and motors as well.