Questions about programming the various LEGO programmable bricks, including Mindstorms (EV3, NXT, and RCX), Wedo and Scout, in either the provided languages and editors, or more advanced languages.

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31
votes
6answers
17k views

Is there any other way to program the Lego Mindstorms NXT other than the provided software?

I'm curious to know if there is any way to program the NXT other than the provided software. I don't necessarily have any issue with the software. Does the program created by the software translate ...
17
votes
4answers
5k views

How to calibrate NXT motors to travel the same distance?

The motors included with the NXT are not all created equal - when given the same input power level, they do not always go the same distance or turn at the same rate. I measured this by creating a ...
16
votes
3answers
2k views

Can you program Lego Mindstorms with the Scratch programming language?

My child is learning programming using Scratch in school. Can she program her Mindstorms using Scratch?
15
votes
1answer
896 views

Can I write programs for the LEGO RCX 2.0 in Java/C++?

Is there a library which makes it possible to write LEGO Mindstorms programs for RCX 2.0 in Java or C++? With the LEGO software it takes so much time to write good programs.
10
votes
4answers
2k views

Can I control 2 NXT bricks from a computer using bluetooth at the same time?

I am thinking about starting a project involving controlling the movement of a mindstorms robot depending on some input from a Kinect device; however the robot will require at least 6 motors. I have ...
9
votes
4answers
3k views

How to make Mindstorms respond differently, depending on which sensor is triggered?

I am new to Mindstorms (but in my day job I am a programmer). I want to make my robot do one thing if the touch sensor on port 1 is pressed, and do something different if the touch sensor on port 2 ...
9
votes
2answers
424 views

Why does this program work in LabView when targeted to computer but not to NXT?

I have a program written in Labview for my LEGO Mindstorms NXT 2.0. When the target is set to the computer, the program works just fine. However, when I set the target to the NXT, the program doesn't ...
8
votes
2answers
972 views

Can we program Nxt2 in C++ under Visual studio 2010?

I'd like to know if it is possible to develop C++ software for NXT2 using Visual Studio 2010 as IDE. I know there are small online projects for NXT but I can't find nothing about NXT2.... Any ...
8
votes
1answer
248 views

NXC Saturation algorithm for limiting motors?

What is a good algorithm in NXC for control saturation? I want to make sure my motors don't turn past a certain angle, or they will break the model. I could do something like: if (angle > 45) ...
7
votes
1answer
392 views

How can I power an NXT motor without the NXT brick?

I know almost nothing about robotics, so I was wondering how can I power the nxt motor without using the nxt brick, and how can I send signals to it?
6
votes
2answers
302 views

Ultrasonic problems with the red and blue balls?

I'm still new to NXT, I try to make the robot locate a ball using the ultrasonic sensor, while there I should be in a square area marked by white color. How can I make the robot locate the object (by ...
6
votes
1answer
220 views

NXT motor power accuracy

When turning the motors, how precise is the speed parameter? I am programming in the NXC language (standard firmware) and wishing to know how many decimal points will be taken, if any, and whether the ...
6
votes
2answers
161 views

Mindstorms start block is missing

the start block is missing on my mindstorms NXT 2.0 programming space. i cannot run any program without it. i have tried, restarting the programming window, placing a block and even just undoing to ...
6
votes
1answer
453 views

NXT brick output ports not working properly

My NXT brick will not let motors run. When I download a program the motor will move forward and backward and then stop - sort of a wiggle. Another motor will not work at all. This happens for all ...
6
votes
1answer
184 views

Is there a way to change the Lego NXT sensor polling frequency?

I am using LEGO NXT 2.0 with the native NXT flowchart-style programming environment, I would love to be able to poll the sensors more frequently. (In particular, it seems that the light sensor is ...
6
votes
1answer
294 views

Is it possible to display large text on an NXT using LabVIEW?

In RoboLab and using RobotC, it's possible to write LARGE text to the screen of the NXT. In RoboLab, this can be done by just typing [\big] at the beginning of a string constant which is wired into a ...
6
votes
0answers
196 views

PosRegEnable - How to change motor parameters?

I want to set PID parameters for a faster 'attack' when using PosRegEnablePID() on a motor. I am compiling with nbc/nxc 1.2.1 r4 mac osx fatbinary using -Z2 and -EF flags. But the compiler says: # ...
5
votes
1answer
429 views

What can cause programmed NXT 2.0 motors to misfunction when small resistance is applied?

I have robot built per the Alligator tutorial included with Mindstorms NXT 2.0. Everything works correctly if I hold it off the ground and make sure there is no load on the two leg motors. However, if ...
5
votes
1answer
72 views

Pass sensor or motor port number as a parameter

I want to create a block for one light sensor or one motor separately. Is it possible to give the number of the port as a parameter to a sensor or motor block via data wire? In NXT-G it was possible.
5
votes
1answer
169 views

Gunner bot programing

I just build the RCX Gunner Bot using the instructions from this web site. I had to build something different to the one we built in the class, I added a touch sensor and light sensor, so the bot ...
5
votes
1answer
442 views

Program a full rotation of a NXT motor in X seconds

I'm interested in mimicking the functionality of the Arqball Spin, at $60 it isn't cheap so I'd like to make the most out of my Mindstorms parts. I'd like to use NXT-G to program a motor to rotate ...
5
votes
1answer
2k views

Mindstorms 2.0 can't download to NXT brick with error 142023

Using Mindstorms education 2.0 on a Windows 7 computer I can't seem to get the program to see the NXT via USB or bluetooth dongle. When connected by USB nothing appears in the NXT window with device ...
5
votes
2answers
914 views

How to program two NXT motors to run at the same time?

I'm working on a project with multiple axis of movement… trying to get two motors to run at the same time in order to achieve a mix of two!
5
votes
1answer
490 views

RobotC for RCX cannot find USB IR Tower

I have looked for similar question but found null. So here I am asking. I have Win7, a RobotC fo RCX and Mindstorms for RCX (both are old version, but available free). I borrowed an old LEGO kit ...
5
votes
1answer
2k views

How to control a RCX from a Mindstorms NXT

I have both an RCX and an NXT. I would like to control the RCX brick from the NXT (and possibly communicate back to to the NXT from the RCX). I would like to avoid purchasing the Mindsensors RCX to ...
4
votes
3answers
574 views

In lego mindstorm EV3, can you make the individual programs in a project into functions which can be used in the other programs?

The bit where you program what the robot does using your computer. I'm making a project and I can't fit it all onto the screen, so if you can't do functions, is there any way to zoom out of the screen ...
4
votes
1answer
2k views

Can you program an RCX using the Mindstorms NXT 2.0 software?

I was asked to teach a robotics class and found several RCX bricks in storage. Can I use these bricks with the Mindstorms NXT 2.0 software? If not, what would be the software I would need to use the ...
4
votes
3answers
152 views

Holonomic robots using Mindstorms

I just got some Rotacaster wheels and want to try building a 3 wheeled Mindstorms omnibot (holonomic robot) and I'm looking for a practical (easy) discussion about writing a driving program. I've ...
4
votes
1answer
174 views

Set to run a program within another program using NXT-G

I'm using NXT-G to program my robot to do few tasks autonomously for so many possibilities. When using C programming, we can call a function from different file into the main program. So, I wonder if ...
4
votes
1answer
189 views

How to build an automatic Lego train system?

I was wondering if anybody has ever tried using the IRLink NXT sensor to make an automated train system and if so, what kind of setup did you have to make it all work? I have been working on a train ...
4
votes
2answers
171 views

How can I find the analog output of a color sensor?

Could anyone provide me with an image of the voltage output of an NXT or EV3 colorsensor. I would like to have the analog output if it's possible, and not the digital output.
3
votes
2answers
57 views

Is there a time mechanism that can be added to an NXT program?

I wanted to create a system where an NXT block would be set into function at a certain time of day (maybe 5:00 and then 5:10 and so on). I would want the timing function to be embedded into the NXT ...
3
votes
2answers
318 views

Is it possible to change the OS in the EV3 Mindstorm Brick

I'd like to know how to change the OS embedded into the EV3 mindstorm Brick ( list of it ). For example, would it be possible to replace the existing one by a linux release without losing any ...
3
votes
2answers
919 views

Invert motor block in EV3

New to EV3 so this should be simple. I would like my simple wheeled robot to go backwards. So I put two invert motor blocks, one for port B the other for port C followed by a move steering block. The ...
3
votes
1answer
56 views

How to minimize the impact of erroneous sensor readings?

A group including myself are using the Lego Mindstorm kit to design a robot that is going to compete in a school competition. However, the sensors aren't as reliable as we would like them to be, ...
3
votes
2answers
168 views

IDE recommendations for EV3 programming

Does anybody have any recommendations for non-GUI programming of the EV3 unit? I'm impressed by the LabVIEW software, but as a professional C# and VB.Net programmer (with C, C++ experience), I find ...
3
votes
1answer
380 views

Can I open my old NXT program files in the new EV3 software so I don't have to rewrite the entire program?

I would like to use or convert NXT-G 2.0 programs for use with the new EV3 software. Is there an easy way to convert them besides just building them from scratch in the EV3 environment?
3
votes
1answer
132 views

Setting priorities in LEGO NXT Programmer

For a sumo bot competition I made a robot that has a perfectly functioning ultrasonic senor. However, when I made a second branch on the program for a light sensor, I calibrated the light sensor and ...
3
votes
1answer
182 views

Is there a microphone that works with Mindstorms EV3?

I'm planning to program my EV3 robot to do voice chat over VOIP using ev3dev and a Debian program. Is this possible? Are there microphones known to work with EV3, and has anyone had experience using ...
2
votes
1answer
39 views

How to make NXT bricks communicate information?

Is it possible to connect, in some way, two NXT bricks that has program functions running on both. For example, Brick one would tell brick two that it is okay to start a program. Are there any sensors ...
2
votes
3answers
937 views

What is a normal range of reading of the Light Sensor using EV3 Raw Sensor block?

EV3 software does not support the Light Sensor. It does support the Color Sensor. The solution is to use the Raw Sensor Block. What is "normal" for raw sensor block readings? I'm getting readings ...
2
votes
1answer
186 views

can't send multiple commands to EV3 using Python

I want to use Python to send commands to an EV3 brick. In C++ things work as expected - for instance, this starts the motor on port A and then stops it after a while: #include <unistd.h> ...
2
votes
1answer
219 views

Can EV3-G MyBlocks be recursive?

Imagine I create a MyBlock called "function1" from a line of blocks. Can I call that block from within itself? This is the program for the block "recursiveTest." Will this block function properly? ...
2
votes
1answer
176 views

NXT Programming not working

I recently got back into NXT stuff (keep in mind I have a NXT 1.0). My screen was broken,but got that fixed. The software works,but I think the programming doesnt. I made it so If I push a button,the ...
2
votes
1answer
105 views

NXT brick erratic programming behavior

I think I have a defective NXT brick. It has been programmed to move in a direction for 1 second, wait 1 second and then move in the reverse direction for 1 second. The code downloads on another ...
2
votes
1answer
65 views

How make robot turning going straight?

I have been struggling with this function for a while. I want my robot to turn left until it detects black then turn right until it hits black again. Then, I will divide the angle in half and call ...
2
votes
1answer
201 views

EV3 Block problems?

I don't see what is wrong with the way i made my program. It looks like this. The idea is that in the while loop [01] shall the robot move forward until it see something brown. If it see ...
2
votes
1answer
29 views

Is it possible to edit a my block input parameter value?

I have created my blocks but want to change the input parameter to a negative. Is this possible or must all the myblocks be re-written?
2
votes
0answers
218 views

Ideas for large NXT projects [closed]

I currently have 6 NXT sets. Can anyone think of some large scale projects that I could attempt using most of the NXT bricks and pieces together?
1
vote
1answer
185 views

EV3 parallel MyBlocks, but only one working

TL;DR = Is there any obvious reason why a MyBlock, added twice in parallel to a program, will only run one of them? In my EV3-G program, I have a MyBlock which uses the Proximity Heading to control ...