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5

If the ultrasonic cannot echo-locate the objects because they're too small, even with the sensor suspended very close to the floor, I suggest using a very sensitive feeler out front. It can be sticking forward like a jousting lance, and your robot can swivel back & forth while traveling to scan. The trick to making it very sensitive is to: (1) make it ...


5

The NXT actually uses IEEE 794 32-bit floating point number format in little endian byte order. I like using this site for conversions. So, to decode your messages: TX: 00 09 00 05 60 EA 00 00 00 Byte 0: 0x00 - response required Byte 1: 0x09 - write message command Byte 2: 0x00 - Mailbox 1 Byte 3: 0x05 - Message size of 5 bytes Bytes 4-7: 0x60 ...


3

Yes, it is possible. Have a look at the "Comm module functions" section of the NXT help file. For example, since the touch sensor status is a boolean value, you could use the SendRemoteBool and ReceiveRemoteBool functions. You can communicate wirelessly using the Bluetooth functions (BT*) or you can have a wired connection using RS485 by connecting input ...


3

You probably don't need it, but the LEGO Education NXT 2.1 Software is still for sale through LEGO Education (at least in the USA). They do not advertise and upgrade price, but it does not hurt to ask. The Energy Meter blocks are available for download on the LEGO Education website. I went to http://education.lego.com/en-us/downloads and checked the box ...


2

I agree with HaydenStudios, it is impossible to disassemble completely NXT motor without breaking the orange axle hub. You can nonetheless half-open it enough to see what's happening inside (you need a Torx screwdriver - T10 size if I remember well - to open it. See photos here http://philohome.com/nxtmotor/nxtmotor.htm. Anyway, first try to see what LEGO ...


2

No, there is no automated way to convert source files from other programming languages into un-compiled NXT-G code. The .rbt format is very complex, so writing a program to interpret programs written in other languages and generate a proper .rbt file with properly placed and configured blocks would be an incredibly time-consuming and tedious task that ...


2

Without 3rd party hardware or software, the only way to do this is to use Bluetooth messages. For example, you could write motor power to a Bluetooth mailbox on one NXT. The other NXT just has a simple program with a loop that reads the Bluetooth mailbox and connects it to a motor block.


2

Raw sensor value works, but shows a level of dark, not of light :), meaning that higher values indicate lower light. Ambient light works directly, but for reflected light you need to insert a EV3 Color Sensor block with Reflected Light mode to turn on the light in the NXT Sensor. After that, use raw values or the Sound sensor block. The Sound sensor block ...


2

If I were you, I'd make it this way: The leader robot has a very bright light shining backwards, but not in a tight beam, rather a wide cone, so it can be seen from the back easily. The follower robot has the light sensor facing forward, with a cowl around and in front of the sensor in order to narrow its sensing angle. In other words, the sensor is ...


2

It could be that one wheel slips more than the other. This happens when the tires get dirty. Also, you can adjust your center of balance so that more weight is on the drive wheels and they will slip less. You can also use the gyro sensor to compensate for any slippage of the wheels.


2

Not sure what language you are using, or calls you are making before this, but: float var_Min = var_R; if (var_G > var_Min) var_Min = var_G; if (var_B > var_Min) var_Min = var_B; Should be (note the use of < rather than >) float var_Min = var_R; if (var_G < var_Min) var_Min = var_G; if (var_B < var_Min) var_Min = var_B; Your posted code ...


2

That's not possible - sensor ports don't have the hardware to drive motors. That said, you can buy a motor multiplexer like this one to do the job for you, if competition rules allow this.


2

https://bitbucket.org/Thad_Hughes/cortex/src Here's something in NXC and python that routes from NXT1 to NXT2 through the PC; emulating a non-master/slave config between all three devices. Has the added benefit of a seamless pairing method. It could be helpful to give a little more detail (what languages you are using, what direction(s) of communication ...


2

PosRegSetAngle should set the position of the motor relative to the position the motor was in when regulation was enabled. In what way didn't it work when you tried this? It sounds like you may be asking how to wait for the rotation to finish. I'm not sure if there is a built-in way to do this in NXC or not, but I think that something along these lines ...


2

There is a modified Color sensor block available here. As of this writing, this is the most up-to-date direct link to download the block.


2

There are many possible ways of doing this. I am a contributor to the ev3dev project, so I am a bit biased in that direction. To do this with ev3dev, I would install the nxt-python package on the EV3 and use it to remote control the NXT. If you want to stick with the standard firmware, another possibility would be to relay bluetooth mailbox messages ...


1

The adapter itself is generally called a "Molex" adapter. The one you have pictured looks similar to their Mini-Latch style. I would recommend an adapter like this. The pin spacing should be the same even if it is not made specifically for that connector. The red wire connects to pin 1 and the black wire connects to pin 2. The yellow wire is for speed ...


1

Since you are trying to solve a Rubik's cube, check out the source code for the MindCuber. The solution there is that the values are not actually converted into colors. Rather the raw values are converted to HSV and then sorted by hue. The actual value does not matter, just how close it is to the other values. The Mindcuber also has a white calibration. ...


1

You have a number of options. Since you mentioned you know C# the best, have a look at http://monobrick.dk. They have a C# library that lets you remote control the NXT. Then you could use something like http://playground.arduino.cc/Interfacing/Csharp to do the same for the Arduino. For Java, there is a similar NXT remote control library from ...


1

I managed to install my license of Mindstorms Edu NXT v2.0 (Windows 7 x64) and the software has Data Logging and the Temperature Sensor Block. If you have an upgrade from v1.0 to v2.0 at least the Temperature Sensor Block will be available.


1

This depends on the exact configuration of your robot, including but not limited to the distance between the wheels (if it's a differential drive robot), the diameters of the wheels, the gearing (if any is used) between the motors and the wheels. A simple solution would be to experiment with various parameters and making corrections based on the direction ...


1

Your best bet[1] for EV3 is ev3dev. For NXT, you should be able to get BricxCC running on Linux. You can also checkout leJOS and MonoBrick. There is a good change you can get either one of those working on Linux as well. [1] As a core contributor to ev3dev, this may not be entirely objective ;-)


1

Yes it is possible. You just need to write a program for NXT1 that forwards the messages from the PC to NXT2.


1

This is fixed using the NXT software version available from http://www.lego.com/en-us/mindstorms/downloads/software/nxt-software/ instead of CD that came with the NXT set.


1

Communicating with the NXT from the LEGO MINDSTORMS EV3 software is not supported. From http://www.lego.com/en-us/mindstorms/support/faq/: 3.10 Is the LEGO® MINDSTORMS® EV3 Home Edition Software backward-compatible with NXT Hardware? Yes. You can program your NXT Intelligent Brick using the new LEGO MINDSTORMS EV3 Home Edition Software. However, ...


1

There are a few options for the cause of the error. It could be at the microprocessor level, meaning that the execution of the program is wrong, or it could be at the motor driver port, meaning that the NXT tries to drive the motor attached to the specific port but can't due to some electrical failure. The first option can be eliminated by using other forms ...


1

The clicking mode means that you need to reload the firmware on the NXT (under the Tools menu in the NXT software). If you still get the overcurrent shutdown using different cables and different computers, then the conclusion has to be that there is something wrong with the NXT itself. The USB port should be drawing little to no current at all since the NXT ...


1

As you suspected, you cannot use the Ultrasonic sensor without an "Intelligent Brick" (EV3 or NXT). MINDSTROMS would be a great way to automate your train if you are willing to make the investment. For more ideas on how to use LEGO MINDSTORMS with LEGO trains, check out Sioux.NET.


1

If the one motor exhibits the same behaviour on any port with any cable and the other motors are working on all of the ports with any cable, then it is safe to say that the problem is definitely with the motor itself. Make sure you swap cables as well as motors to rule out a faulty cable. Also, check for signs of corrosion on the pins of the cables, motors ...



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