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The NXTCam from mindsensors.com

Vision systems are one of the more useful, albeit trickier, sensors that can be used in a robotics system. They allow a microcontroller to literally ‘see’ an object, its color, shape, and (in some cases) the material it is made from. They are used extensively almost anywhere an automated system needs to make a decision based on an object’s visual properties.

Fortunately, MindSensor’s NXTCam combined with Xander’s driver suite allows NXT users to quickly and easily program a vision system for their robots. ROBOTC forum member alain has recently created one of the basic NXTCam robots (a robot that will track a colored ball with relatively high accuracy) and was kind enough to share his programming journey on the ROBOTC forum and the video below.
 
 
 
 
 
 
 

If you’re interested in building your own color-tracking robot or have other, unique ideas for an NXT cam with ROBOTC, be sure to check out the Robotics Academy demo video for ideas on how the NXTCam can be used and the ROBOTC forum for coding help.

We ran into Paul Utley from Pitsco at the 2013 FIRST Championship who designed a model of the Curiosity Rover with TETRIX parts, NXT brick, and programmed in ROBOTC! We were lucky enough to get a short interview with him about it. Check it out here …
 
 
 
 
 
 
 
 

The Robot Virtual Worlds team has been developing a multiplayer game mode, and our group was lucky enough to get a sneak peak last week (and I made sure to record the event for you!)

Check out the video from the preview:

It will work with ROBOTC, have CS2N connectivity for achievements, private rooms so only the people you invite will be allowed in, structured chat rooms, and a lot more!! Look for it to be released at the end of the summer.

What do you think? What features would you like to see included in it?

Martin Mason, professor of Physics and Engineering at Mt. San Antonio College and ROBOTC user, has developed a new VEXduino Shield. He created a board that you can plug in VEX sensors but, combined with ROBOTC, uses an Arduino to control the robot instead of a Cortex or PIC. Combining the Shield with an Arduino, some VEX parts, and a small breadboard is a perfect recipe for teaching electronics with the ROBOTC for Arduino!

Read the rest of this entry »

Just like many of you, we have to get creative with the tools we have around us for different tasks. Today was no different. Tim is reformatting a computer today, and long story short, needed to click the “retry” button every time a window pops up. To make sure we didn’t have him wasting his day pushing a button (you’d like ROBOTC 3.6 released one day, right?), we made a VEX ‘auto-clicker’ to get the job done. Check out our picture and short video …
 
 

While scouring Vimeo a couple weeks ago, I came across a “Vimeo Staff Pick” time-lapse video featuring beautiful landscapes, lakes, mountains, and skies called “Hdr Skies.” When looking in the description for more details, I noticed that ROBOTC was listed! I sent the creator, Tanguy Louvigny, an email to learn more about his process with ROBOTC and time-lapse photography. He was nice enough to answer some questions for us …

- When did you start using ROBOTC?

I started using ROBOTC some 3 years ago, when I started my TETRIX based time-lapse rig project.

- What made you decide to program your time lapse rig with ROBOTC?

Version 2 of my rig used three motors to move the camera on three different axis, and was thus more complex to program. That’s when I decided I needed something more convenient and powerful to be able to control the TETRIX encoders and synchronize the motors with the camera shots. ROBOTC was the solution to my problems and worked like a charm.

- What did you use to build your rig?

My goal with this project was to construct a motorized base for my camera to add movement in my time lapse clips. The first, one axis version of the rig simply used a LEGO MINDSTORMS NXT 2.0 kit to support the camera. For version 2, I needed more robust parts and powerful motors to be abled to sustain the weight of new and bigger cameras, so I went for a TETRIX kit that I would couple with the MINDSTORMS brick to control the motors.

- How long was this video in production?

The ”Hdr skies” video was a compilation of one year of time lapse shots. Since then, as I shoot more, I try to achieve a new video every six months or so.

- How has your experience been with ROBOTC?

I had a great time programming with it, I already knew a bit of C, so I found it very easy and natural to use, in fact so simple I was rapidly able to code all my ideas with ease!

- Do you have any other projects coming up that you are using ROBOTC with?

My next project is a new TETRIX based five axis rig using a motorized jib. I’ll use ROBOTC to control the motors and build a new MINDSTORMS interface to program the moves. I’m also exploring new possibilities to use ROBOTC to fire the camera directly, thus simplifying the robot/camera synchronizing part.

Tanguy also mentioned that all his time lapse videos are made with the rig.

Thank you so much Tanguy for sharing your awesome project! Do you have a cool projects that you created using ROBOTC? If so, let us know! We’d love to feature it here.

When it comes to setting up any new robot, the age-old saying ‘knowledge is power’ tends to ring particularly true. This is why one can find a variety of beginner guides already available, such as the Video Curriculum Trainer and the ‘Getting Started with NXT and TETRIX’ ROBOTC wiki guide. There’s no such thing as too much knowledge, though, and the more tools a roboticist has at their fingertips the higher their chance for success.

Because of this, we are pleasantly surprised by the depth of content covered by Avi, aka TheProgreammerDude’s YouTube tutorial video. Avi is a member of FTC team 5773. Not only is his tutorial straight from the screen of an FTC team programmer, it focuses on ROBOTC programming concepts specifically for the FTC competition (such as using competition templates and setting up a TETRIX robot using the Motors and Sensors Setup window).

If you’re looking add this video set to your ROBOTC toolkit, be sure to check out the first video in his series.

Screen capture of a ROBOTC program being edited in Sublime Text Editor

ROBOTC community member Mike McFarlane has recently released a plugin for the popular Sublime Text Editor. This new plugin will allow users to edit .c files on both Linux, Mac, and Windows platforms, which can then be opened and compiled in ROBOTC (the Sublime Editor will not be able to compile the code to a robot, unfortunately).

Quote from Mike (full post on the ROBOTC forum):
“I’ve written a plugin for the elegant and productive Sublime Text editor that will allow you to create and edit RobotC code on Mac, Linux and Windows. It’s got autocomplete on the full set of RobotC functions and variables, search via functional and platform category, tabbing between a functions values, syntax aware colouring and code snippets. Only v0-2 right now, but it works…It’s not possible to compile or debug outside the RobotC IDE, but I’ve got some ideas on ways to get the files quickly in and out the IDE.”

For more information on the new plugin, check out Mike’s blog post. If you are comfortable with the Sublime Text Editor and wish to download the plugin directly, you can do so from this site.

Any features you’d like to see added in the future?

Miniaturized SPRAT model controlled by 3 NXT bricks using ROBOTC.

ROBOTC community member Didier Coll has created more than a few awesome robots. In the past couple of months, though, he has made some truly spectacular bridge-laying robots using ROBOTC over multiple NXT bricks.

The first creation is an AMX-13 type bot, which (unlike the other two robots) carries the bridge on its front. Like the MLC-80 though (below), the AMX-13 is programmed to place the bridge and then drive across: it uses 2 motors and 8 actuators controlled via 2 ROBOTC-coded NXT bricks to achieve this goal.

The second robot is based off of the French Army’s current EFA design. Much like a real EFA, the robot drives to the middle of the ‘river’ and extends the folded bridge sections using a series of LEGO pistons; the robot stays in the middle of the bridge and the other robots effectively drive over it. The EFA model uses 2 NXT’s, 3 Multiplexors, 4 motors, and a staggering 10 actuators to perform this task.

Didier’s final robot is a replica of the SPRAT MLC-80 used during WWII. It uses 3 NXT bricks, a whopping 9 motors, 9 actuators, and 5 servos to place the bridge and drive across it, all controlled by ROBOTC for MINDSTORMS. A sample of the ROBOTC code used for this robot is below.

#pragma config(Sensor, S1,     HTIRL,          sensorI2CCustom)
#pragma config(Sensor, S2,     PSPNXV4,        sensorI2CCustom)
#pragma config(Motor,  motorA,           ,             tmotorNXT, openLoop)
#pragma config(Motor,  motorB,           ,             tmotorNXT, openLoop)
#pragma config(Motor,  motorC,           ,             tmotorNXT, openLoop)
//*!!Code automatically generated by 'ROBOTC' configuration wizard               !!*//

//*!!Code automatically generated by 'ROBOTC' configuration wizard               !!*//
///----------------------------------------------------------------------------
/// didier  TWO MASTER SLAVE NXTBee modèle
//  NXT MARRON
///
///
///----------------------------------------------------------------------------

#include "drivers/mindsensors-ps2ctrl-v4.h"
#include "drivers/hitechnic-irlink.h"
#include "ROBOT DATA SPRAT 3 NXT ONE.h"
#include "didier GESTION SPRAT 3 NXT ONE.h";

///////////////////////////////////////////////////////////////////////////////

task main()
{
bNoPowerDownOnACAdaptor = true;   // will NOT power down when connected to AC adapter

bFloatDuringInactiveMotorPWM = false;  // the motors will NOT coast when power is not applied

StartTask (ROBOTData);
StartTask (gestionSPRAT);

while (true)
{
wait1Msec(10);
}
}

Want to see more pictures, videos, and information on these bots? Have any thoughts, comments, or questions? Check out Didier’s forum posts (links above) or comment below!

Looking for an awesome opportunity to test your ROBOTC skills this spring? Our friends at Parallax have the solution: the 2013 National microMedic Contest. The microMedic contest challenges participants to create cool, open-source medical devices powered by microprocessors and sensors. To motivate inventors to think outside-of-the-box, the microMedic challenge is giving away 100 free contest kits on a first-come, first-served basis and is also offering prizes to the winners of the contest (over $25,000 rewarded across 25 total winners). There are no restrictions on hardware or programming languages, so this is the perfect opportunity to hone your ROBOTC expertise with the VEX, LEGO, or Arduino platforms. For more information, please see the contest’s article on CS2N or the contest homepage on Parallax’s website.

“The U.S. Army’s Telemedicine and Advanced Technology Research Center (TATRC), Carnegie Mellon University Entertainment Technology Center, and Parallax Inc are offering over $25,000 in prizes to inspire the next generation of medical innovation. The 2013 National microMedic contest is an opportunity to show the country what citizens can do with new technology – encouraging technical innovation with significant use of microcontrollers and sensors in the medical industry. This contest is perfect practical application for STEM (Science, Technology, Engineering, Math) students around the nation.

The 2013 National microMedic Contest will create significant interest around new open-source medical applications. TATRC’s Dr. Brett Talbot, Medical Simulation Portfolio Manager, says about the contest “we’re looking for microcontroller-based projects for the health and medical simulation community that combine the latest use of sensors, 3D printing, CNC and science disciplines. This is a call to action for inventive people to put our skills to use for the benefit of Army personnel and civilians.”

Inventors and students are encouraged to participate by creating medical applications and products for possible use in the healthcare industry, medical simulation training, and the battlefield. STEM teachers are encouraged to get their classes involved. Over 100 free contest kits valued at over $40,000 will be given away on a first come first serve basis to qualified applicants. Use your favorite microcontroller or apply to receive a free kit that includes either the Parallax multi-core Propeller chip or a shield for use with the Arduino microcontroller. The kit also contains various sensors, LED displays, infrared emitters, a blood pressure cuff, heart rate monitor and many other components to spark your imagination. Use of the official contest kit is not required to win.

To help get competitors started Parallax Inc. is hosting resources such as mini tutorials with code examples for sensors, lists of application ideas and an online discussion forum specific to the microMedic National contest where contestants can ask questions and collaborate. Applicants have until July 31st, 2013 to submit their microMedic entries. Over $25,000 in prizes will be awarded to 17 educational winners and 8 winners from the public category. The award ceremony will be held in September 2013 at the TATRC Innovation Lab in Fort Detrick, MD. For more information on the 2013 microMedic Contest visit Parallax’s website.”