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Archive for April, 2012

Bucket ‘o’ Bricks Brick Sorter

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NeXT-Generation, over on the ROBOTC forums, posted a very cool project he’s been working on for the last two months.  It’s an automated brick sorter made with a combination of Mindstorms NXT, Power Functions and Pneumatics.


YouTube Direct Link 

The video might be long but it’s well worth watching!

Naturally, we asked him questions about his creation:

What motivated you to make this?

I wanted to build a robot that was interactive and would entertain smaller kids, and be mechanically interesting to older ones, and even adults. Here’s what happened: I planned for it to be able to “learn” where the colors were supposed to go. You could tell it if it put the brick in the right or wrong area until it learned where they all belonged. But, mechanical glitches in the construction that I didn’t have time to fix prevented that from happening. I probably would have made another console with the other NXT with the yes/no buttons, and it could make sounds and use the display to interact.

How long did it take?

Well, if you count total time it’s been built, about two months. But, now here’s the catch: I’ve really only been working on it for about one month, because I got sick twice over the last two months, so in total I was out of it for about a month. During that month I was also working on other stuff. Probably about a week was lost to messing with my Boe-Bot and Pololu 3Pi.

Do you have any plans for future improvements or modifications?

I plan to revisit the same kind of concept, but with no deadline so that I can work out any problems that come up.

What is the average air speed of a laden swallow?

The average airspeed of a laden swallow is 42.

A very cool project, indeed!

Written by Xander Soldaat

April 30th, 2012 at 11:46 am

Posted in Cool projects

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Full Set of Possible Characters for VEX LCD

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Full credit for the work behind this post goes to ROBOTC user Matthieu V. Thanks Matthieu!

The VEX LCD is a fantastic tool, allowing you to display messages and values on the robot with very little effort. Some programmers even use a combination of the screen and input buttons to create a basic user interface on their robots – allowing them to choose between multiple autonomous routines, choose a specific sensor and display its values, and more.

What many programmers don’t know, is that there’s a wider selection of symbols that can be displayed with the LCD! Shown below is a full list of characters that can be displayed, along with their numerical equivalents, in a useful table Matthieu put together.

 

Full character look-up table:

You can download a printable PDF of the table, along with some additional notes, here.

To display any of these custom characters, you should use either the displayLCDChar(); or displayNextLCDChar(); commands as you normally would, but specify the numerical value instead of an actual character in single quotes. For example, the following code will display a right arrow on the very first position (0,0) on the LCD:

task main()
{
//Create and initialize variable x
//Value stored in x must be between 16 and 255
int x = 199;

//Clear Line 0
clearLCDLine(0);

//Display the character associated with the value in x
displayLCDChar(0, 0, x);

//Wait 5 seconds before the program ends, clearing the screen
wait1Msec(5000);
}

Written by Jesse Flot

April 27th, 2012 at 1:58 pm

Posted in Cortex,General News,PIC,VEX

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LIVE pictures and videos from 2012 FIRST World Championships in St. Louis

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We’ll be continually updating this blog post to put up any awesome videos we grab from the 2012 FIRST World Championship in St. Louis.

TETRIX Shooter bot

 

Humanoid TETRIX robot

 

NXT Gyro Balancer with Bluetooth remote NXT

Check out this video! It’s an NXT that is using a Gyro Balancer in order to keep itself up. But that’s not all! It’s also using a Bluetooth Remote NXT to control it.

Check out our Facebook Gallery as we update it!

Our 2012 FIRST World Championship Gallery on Facebook

Written by Vu Nguyen

April 26th, 2012 at 10:28 am

Posted in General News,NXT

Neat video of an NXT game made in ROBOTC

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Here’s a neat video we found of a user who made a Pong / Brick Breaker type game in ROBOTC.

They’re using a wheel in order to control the platform to keep the ball from exiting the screen.Take a look!

Written by Vu Nguyen

April 24th, 2012 at 10:10 pm

Posted in Cool projects,NXT

NEW! VEX Speaker module and ROBOTC Support

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Got a new VEX Speaker?

VEX Robotics just announced (and released) their new Speaker accessory for the VEX Cortex Microcontroller. This cool new speaker will allow you to play tones, sounds and wave (.wav) sound files from your VEX Cortex. The new speaker plugs into the “SP” port on the Cortex – check near the bottom of the sensor bank of ports. The speaker even has a built in volume control:

Check out our cool unboxing photos below, exclusive from the VEX World Championships!

[scrollGallery id=5]

The awesome thing with this new speaker accessory is that ROBOTC already has support for this new speaker built into version 3.08! For more information on how to use the speaker, check the ROBOTC help documentation built into ROBOTC, or look at our new (under construction) ROBOTC code wiki!

Wiki Link: http://www.robotc.net/wiki/VEX2:_Functions_-_Sound

To help you get started, here are two sample programs to try out your new VEX speaker attachment.

Sound Test:


task main()
{
//Basic "Play Sound" commands
PlaySound(soundBeepBeep);
wait1Msec(200);

//Intelligent "Play Sound" command
//Delay until sound is done playing
PlaySound(soundFastUpwardTones);
while(bSoundActive)
wait1Msec(1);

//Play a tone:
//First Parameter: Frequence in Hz
//Second Parameter: Length to play in 1/100th of a seconds (50 = .5 seconds)
PlayTone(440, 50);
wait1Msec(500);

//Play a Sound File (need to use the File Management to Upload First)
PlaySoundFile("1.wav");
wait1Msec(1000);
}

In addition, we also have some sample sound files that you can try out. Lastly, we also have a set of PowerPoint slides that go in-depth on how to use the new sound functions as well.

Sample Program Downloads:

Powerpoint explaining the VEX Speaker:

Sound Files:

Written by Vu Nguyen

April 20th, 2012 at 11:55 pm

Posted in Cortex,General News,VEX

New ROBOTC Firmware for VEX Cortex Users with Integrated Motor Encoders

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There have been reports of the VEX Cortex locking up when using the new Integrated Motor Encoders. The root cause appears to be an unhandled exception that is generated when the I2C communication link between the Cortex and encoders is compromised. To prevent the Cortex from locking up, we’ve put together a new ROBOTC Firmware file that handles the exception. The differences between this new firmware and the version included in ROBOTC 3.08 only apply to the new Integrated Motor Encoders, so users who aren’t taking advantage of them should continue using the firmware included in ROBOTC 3.08. VEX Robotics Competition teams that are using the encoders are encouraged to load the new firmware, and to take extra steps (zip ties, ect) securing the 4-pin I2C wires, to help prevent them from coming loose in the first place.

The new ROBOTC firmware, “VEX_Cortex_0912A” can be downloaded here. Once the file is downloaded, you will need to extract the .hex file from it.

To transfer the firmware to your Cortex:

  1. Open ROBOTC
  2. Go to Window > Menu Level > Expert
  3. Make sure the Cortex is connected to the PC over USB or VEXnet
  4. Go to Robot > Download Firmware > ROBOTC Firmware > Choose File…
  5. When the File Selection window appears, navigate to the “VEX_Cortex_0912A.hex” file you extracted and select it
  6. A Download Progress window will appear in ROBOTC and begin the download
  7. When the Download Progress window closes, the Firmware download is complete

More information on the problem can be found in this post on the VEX Forums.

Thanks to everyone for submitting your testing results, and for your patience as we work out the issues. A special thanks goes out to VEX Forum user, jpearman.

Written by Jesse Flot

April 14th, 2012 at 3:37 pm

Sneak Peek: Robot Virtual Worlds Release

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Robot Virtual Worlds (RVW) has announced a new release scheduled for this Friday, April 13, 2012!

Among the modifications in this release are new utility tables, new challenges, and new robots!  Check out the blog release here!

 

Not familiar with Robot Virtual Worlds?
RVW allows students to use their ROBOTC code on virtual robots in a simulated environment. Students will be able to write and test code in RVW and then export the same code into a real NXT or VEX robot.

With RVW, students do not have to purchase a robot, they can compile and test code much quicker, and they can use robots in fantastic environments that are unthinkable to do in the classroom!


Written by Luke Reynolds

April 11th, 2012 at 10:02 am

Posted in General News

NXTBee Programming for ROBOTC

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Mark Crosbie over at www.mastincrosbie.com put together a really nice library for the NXTBee. The article provides detailed information how his NXTBee library works and Sample Programs to try out a few behaviors.

You can take a look at it here:

http://www.mastincrosbie.com/Marks_LEGO_projects/NXTBee_Communication_Library.html

The article also provides a nice explanation of how communications protocols are structured, and also talks about data types.

Written by Vu Nguyen

April 10th, 2012 at 4:14 pm

Posted in NXT

VEX Robotics World Championship Firmware Update

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VEX Robotics has released the following information on their website:

The VEX Robotics technical support team has identified an issue that some competition teams are experiencing in which the Cortex Microcontroller is unable to resume VEXnet link after a Microcontroller reset.

To help eliminate this issue at the VEX Robotics World Championship we are releasing a special version of the VEX Firmware, specifically for World Championship teams (3.21_Worlds). This firmware version modifies the Cortex re-initialization to help the VEXnet link reconnect in the event of a reset (i.e. caused by VEXnet Key “jostling”, power interruption, battery brownout, or static).

We know that competition teams dislike updating firmware so close to an event, so we are publishing this update in the hopes that teams will have a chance to test it “at home” before coming to VEX Worlds. If you’re comfortable with the new version, we strongly urge you to use it at the World Championship to help prevent potential problems related to a Cortex reset.

This firmware only updates a “back end” relinking protocol and it does not affect anything related to robot performance — you don’t need to tweak your autonomous mode, or anything like that.

Visit the VEX Forum thread on this firmware release for more discussions and to post any questions or concerns.

Download the 3.21_Worlds Firmware Update.

We’ve done an array of tests and the firmware is compatible with ROBOTC 3.08. User jpearman of the VEX Forums has also posted his test results, here.

We recommend that all competition teams update to ROBOTC 3.08 and use the 3.21 Worlds firmware. The firmware can be downloaded using the VEXnet Firmware Upgrade Utility, or ROBOTC using the following procedures:

1) Connect the Cortex to the Computer over USB

2) Switch the ROBOTC Menu Level to Expert:

3) Go to Robot > Download Firmware > Master CPU Firmware > Choose File…

4) Navigate to VEXnet Firmware Upgrade folder in your Program Files directory and select “CORTEX_V3_21_Worlds.BIN”.

5) Press Open to open the firmware and begin the download process.

6) Once the CORTEX_V3_21_Worlds.BIN Master firmware has finished downloading, you should also download the ROBOTC firmware. Go to Robot > Download Firmware > Manually Update Firmware > ROBOTC Firmware > Standard File.

Written by Jesse Flot

April 5th, 2012 at 3:59 pm

Setup Tutorials Updated in the VEX Cortex Video Trainer

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One of the major improvements recently made to ROBOTC was the ability to “Automatically Update the VEX Cortex” and “Automatically Update the VEXnet Joystick”.

The new functionality has been very well received, saving Cortex users lots of time and effort. To reflect the improvements in ROBOTC, we’ve updated the Setup materials in the VEX Cortex Video Trainer.

We’ve also simplified the Cortex setup process by splitting the instructions into two tracks: wireless and wired instructions. The new materials can be found in the Setup > System Configuration section.

Written by Jesse Flot

April 5th, 2012 at 12:25 pm

Posted in Cortex,VEX

Tagged with