ROBOTMAK3RS Blog

The Coltar  (or Colour-Guitar for those of you not as cool!) looks like a fantastic little project. YouTube user Philipp Lenssen has put together a nifty little guitar that gets its cues from a coloured fingerboard and a colour sensor.  Place the sensor over a different colour and get a different note - simple but effective. What makes it stand out over similar projects ( like my very own sequencer ) is that a button on the side changes the chord that the colours relate to.  This allows him to create songs by following a set chord progression.

From the guys who brought you the C5 NXT Blimp , have a look at this awesome industrial color and size sorting plant commissioned by Dynaway . T his model is used to demonstrate their manufacturing execution system. It sorts 2x4 and 1x2 bricks in size and color. The bricks get sorted directly into pallets in a high bay storage system. When a new color is detected, an empty pallet in the high bay storage is assigned to the color. When a pallet is full, a robot retrieves it, and returns a new empty pallet.  There are 7 NXT’s in the plant, and they all communicate with each other and a PC application over Bluetooth. The software written in leJOS, with is a java language for MINDSTORMS®. Full details can be found on the  BrickIt    team's website

Xander over at BotBench has a great post on the inner workings of the official LEGO Color sensor. He took to it with a knife to explore the insides and how it works. I won't spoil it, but there is a fantastic little twist at the end so read the whole thing :) via BotBench -  http://botbench.com/blog/2011/09/16/exposed-lego-colour-sensor/

The relentless sensor makers of  HiTechnic have released a new sensor for the NXT: the barometric sensor . It can be used for measuring both the atmospheric pressure as well as its temperature. From the web page: "The pressure value from the sensor is in 1/1000th of inch Mercury (inHg) and the temperature is in 1/10th degree Celsius. The NXT-G block allows the NXT to read the pressure in either inHg or hPa (hectopascals) and temperature in either Celsius or Fahrenheit degrees. Once adjusted for current conditions, the block can also calculate altitude in feet or meters." As usual, HiTechnic also provides support for the new sensor in NXT-G as well as in RobotC . By experience I'm positive that other NXT platforms like leJOS NXJ or NXC will integrate support soon, too.

I haven't had a lot of time lately to work on hobby robotics*, so instead of waiting until my current project is finished, I wanted to share some of the development of this new project. Here's a video that shows two sub modules of it in action. The new project isn't something unique. In fact, it's just another NXT brick sorter. However, since I'm not limited to one-set constraints, I tried a few things I haven't done before. The sorting machine that I intend to build is a little bigger than otherwise, and it's also a bit smarter. For example, it is now able to identify the size and color of a brick no matter its orientation. My older sorters required bricks to be placed in a straight chute, one by one in a sequence. Additionally, the idea is to make it fully automatic. That is, just throw in a big pile of bricks and wait while they're being sorted. *The joy of an engineering degree is that you get to build robots outside your hobby, too! I hope to be abl...

This Checkout Scanner project I posted recently uses the NXT 2.0 Color Sensor in Light Sensor mode to scan simple "barcodes" made out of LEGO beams and imitate a laser barcode scanner. The interesting thing is how fast it is able to work (the standard light sensor would be as fast as well). Here is a video of the scanner in action: This project was inspired a bit by one of the missions on the FLL board this year, the Medicine Dispenser, where teams might want to use a light sensor to count black lines on the mat to get the exact distance right. My team was doing this mission and driving very slowly to make sure the sensor was able to count the lines properly. As I was watching them, I was thinking this was one of those cases where your instincts as a human don't relate well to what a robot can do. I knew the sensor could work much faster (and therefore the motor response is the limiting factor, not the sensor), but I was curious how much faster. So I did some tes...

Here is a little eye candy just for fun. I was taking pictures of my most recent project (post coming soon), which uses the LEGO color sensor in light sensor mode, and I was surprised to find the following image of its red LED in one of my pictures: This is not Photoshopped, the star-like rays appeared on their own, I guess due to an interaction between the shape of the camera aperture and reflection/refraction/diffraction between the different lens elements. This is with the red LED shining brightly, as it is in light sensor mode with red illumination (or red lamp mode). The photo was taken at f/16 for 0.8 seconds with fairly bright but diffuse ambient lighting, and a fixed (prime) 50mm lens. So then I had to try the other colors. Notice how the different wavelengths of light cause different diffraction effects. Or is this just differences in the LEDs themselves? Getting a similar image in color sensor mode, when all three LEDs are shining, was harder, because the LEDs are much d...

This Vending Machine project is one of the "bonus projects" available on the CD LEGO MINDSTORMS NXT 2.0 by Example from nxtprograms.com . A preview and video of the project are available on the website (see video below), and full building instructions and the fully commented NXT-G program are available on the CD. Built with a single NXT 2.0 kit, the machine displays four LEGO parts for sale on the rack in front. The colored balls act as different coin values, with the color sensor detecting them as they are inserted. Using the display and buttons on the NXT, you choose your item from a menu on screen, then you insert balls to pay for it. If you inserted enough money, the selected item is dispensed down the slide in the front, and if you inserted extra money, the machine automatically computes and dispenses the correct amount of change via a hidden change reservoir into the change cup in front. The machine also handles various other error cases such as not inserting enou...

NXT user Robin Newman has started a cool new web site where he fully documents three different ball sorting robots he designed for NXT 2.0 (and I hear another one is on the way). Included on the site are full building instructions with photos, programs, videos, and a nice description of his design process and experiences working on these. Nice work Robin! Check it out.

Ronald mcRae, creator of some impressive models, build this supersized MINDSTORMS 1.0 ball sorter. Check out some if his other models too. Martyn

I have received a lot of questions and requests about line following over the last several months. Some requests are coming from the FLL direction and such, but also users of the NXT 2.0 retail kit are wondering how to do line following using the color sensor, which is somewhat harder and/or less obvious than with the (NXT 1) light sensor. So I have posted this NXT 2.0 Line Follower project to show two ways to do this (there are many other approaches), a simple "Two State" line follower program, and a more complex "Proportional" line follower, which is smoother and faster. In addition, the Proportional version includes an automatic calibration sequence, where the robot automatically scans the line and surface to determine the minimum and maximum expected brighness values on its own. These programs will only work on NXT 2.0. I will follow up with some info and programs for NXT 1.0 users later. Although under good conditions you can make a simple line follower using ...

Philo has just put up a really well-done comparison of two of the color sensor that are currently available for the NXT. The first is the official one from LEGO, included in the V2 NXT kit, while the second is the HiTechnic V2 color sensor which can be purchased separately. I'm not going to bother summarizing Philo's excellent presentation too much, because reading it is an education in itself - not just on how the sensors "perform", but on how to compare sensors properly: developing tests, and understanding the results. Please read his page for the whole scoop. A dirt-simple summary is both have strong points, with the HiTechnic one being amazing at detecting multiple colors and handling challenging ambient light conditions, and the LEGO one (by virtue of using the rapidly-reading AtoD converter on-board the NXT) being much faster (probably important for line-following, for instance). Thank you Philo for doing comparisons like this - and please read his summary , it...

For any FLL teams using the NXT 2.0 kit, note that the color sensor is not allowed in the FLL competition. The FLL rules allows for up to 2 "Light Sensors", and this refers to only the original NXT light sensor or the older RCX light sensor. The Color Sensor is not allowed, even if you only use it in "Light Sensor" mode. I verified this with FLL to be sure, and they confirmed. So if you have the NXT 2.0 kit, you can buy the original NXT light sensors separately from LEGO Retail or from LEGO Education .

More information and pictures are found on the MINDSTORMS news page and on the LEGO shop website .

This is the parts list inventory of the new set. Notice that the set also includes 4 wheels with tyres, even though the latter parts are not used in any of the set models. The box includes more smaller beams than the old set, and the amount of length-15 beams is reduced to 2. However, you get a lot of other useful beams in return. Apart from new parts, some of the older parts have a different color. Here's a more detailed picture of the back side of the box. Two new features of the software are shown here: Remote control (USB or BlueTooth) and the possibility to create custom sounds and image files for the NXT. The box also promises 10 models with downloadable building instructions from mindstorms.com upon the set's release. Two of the models are shown here. One of them is a six legged Mantis, and the other one is a cool transforming robot. This image is not very new, but it shows the color sensor functionality, with three separate functions: - It can be used in Color Sensor Mo...

One things I'm always keen to explore is the use of MINDSTORMS in ways that are not immediately obvious. I was lucky enough to have the chance to play with the new colour sensor that will ship with the 2.0 kit and came up with this little music sequencer. Each coloured ball represents a different note. As the colour sensor passes over the top, the note assigned is played. Different rhythms are possible by placing the zamor spheres in different places on the holder. Inspiration for this came from the BeatBearing project. http://www.beatbearing.co.uk/ -- Damien Kee

New images from toy fairs all over the world slowly pop up. Gadget review blog Pocket-Lint states , "Mindstorms NXT 2.0, will focus on offering 10 to 14-year-old boys a good robot experience rather than trying to appeal to the hardcore fans that use the kit. Other new features include the inclusion of ten robot instructions from the software rather than two as in the previous model." The article also tells us that this kit will cost around £200, which is about $285. However, these prices may vary per country: LEGO usually has different prices for different countries. If follow the article link and click on more images , you will also see something which appears to be a new NXT- G feature, a remote control. This would suggest that the kit comes with newer software than version 1.1, which currently ships with NXT kits. Update: One of readers correctly states that the target audience referenced on the Pocket-Lint blog doesn't cover the complete audience. Of course, Mindstorm...

I was just surfing the HiTechnic Website when I found that they have released a new sensor. The Electro Optical Proximity Detector or EOPD is used to ...accurately detect objects and small changes in distance... The sensor has its own internal light source so it won't be disturbed by external light signals. Objects can be detected from distances up to 30 cm. Has anyone got or tested this sensor - if so please comment and share your experience with the rest of us. Anders

Watching a typical multi-degree-of-freedom robotic arm can be a joy. Separate from precision welding on car frames, they sometimes seem to have a life of their own, and the way they seem to dance and flow is almost mesmerizing in some cases. PnP ("Pick and Place") was built for a couple of reasons - first, because it was fun, and second, because a number of folks seemed to think it would be hard or impossible. It started as part of a challenge that involved building LEGO using only LEGO - a hard challenge in the first place, but we were trying to do it with only the parts available in a NXT kit. A lot of folks commented that this would be "very difficult" without some easy mechanism for linear motion, like gear racks... but I wasn't convinced. First, there were other ways to generate linear motion (lead screws, or certain mechanical linkages). And second, I wasn't sold that linear motion was required... so I set out to do it without linear motion, and using...

I've received a ton of emails about The Mayan Adventure over the past year or so, and I'm glad to hear that so many people have enjoyed the book. I've heard from students, teachers, and parents about the different ways they've used the book - classroom, camps, and parent/child activities. (I've even been asked to teach a camp class this summer that will use the book.) Teachers have been the most vocal - asking for more information, more activities, more of everything! Well, here's what I've got so far... I've developed a 3-part module series for teachers/coaches called "Mystery Warehouse." Like The Mayan Adventure, it uses a fictional storyline to encourage more activity (building and programming) with the NXT kit. Each module is broken down as follows: * Instructor Resources -- Two Pre-Challenge Activities - These give the students experience using and programming each sensor used by the robot in a particular module -- Module Main Challenge - ...