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.

learn more… | top users | synonyms

1
vote
0answers
14 views

Access WeDo on OS X from a real programming language

I'm trying to talk to the WeDo USB interface from Python or really any real programming language. I tried the clever WeDoMore library, but can't get it to bind the WeDo. I think this is because the ...
3
votes
1answer
59 views

Custom EV3 Block: “Unable to compile…” (“string subsection”)

I am attempting to make a custom block according to the EV3 Block Developer kit (found here). I was able to create a simple block that returns the length of a string. This is what it looks like: (The ...
2
votes
1answer
45 views

Have Multiple Inputs to Programming Block

Originally, I had a simple program to move until the robot hit a wall, then it reversed and turned and moved again, repeated to infinity. It works by turning the motors on, waiting for input from the ...
1
vote
0answers
32 views

Tufts MAZE LabView Program Will Not Run on EV3

Through the 2012 LabVIEW for LEGO software package, I found an example of a maze from Tufts. I cannot get it to run on an EV3. It appears to just constantly execute the initialization. How can I ...
0
votes
0answers
63 views

RGB To HSL Algorithm? [migrated]

I have seen many algorithms and formulas for converting RGB data to HSL but none were successful. So where can I get few algorithms/formulas for converting.
0
votes
1answer
105 views

Raw RGB data to Color?

I'm trying to convert the raw RGB values from a Colour Sensor into HSL but it doesn't seem to be working: R = rgbn[INPUT_RED]; G = rgbn[INPUT_GREEN]; B = rgbn[INPUT_BLUE]; var_R = ( R/255 ); var_G = ...
0
votes
2answers
65 views

Programming NXT color sensor with NXC?

I am programing Lego Mindstorms NXT 2.0 color sensor in BricxCC. I already have RGB data with the command ReadSensorColorRaw. I heard that it is easier to get the colour from HSL format. I've tried a ...
2
votes
1answer
92 views

How can I rotate an EV3 motor an exact number of degrees using RobotC?

I'm trying to rotate the motor of an EV3 by an angle of 50°. I can't. How I can rotate a NXT/EV3 motor by a given angle using RobotC?
1
vote
0answers
63 views

Programming the LEGO Mindstorms T-Rex [duplicate]

I followed the instructions up to the MoveAbsolute My Block for the T-rex but I'm not able to link the last connection (Brake at End). Can anyone advise what I might need to change?
2
votes
1answer
35 views

I need a block that can combine a movement program with NXTbee radio

I am a student. I am working on a science project using LEGO Mindstorms robots enhanced with NXTbees creating a mesh network. My engineering mentor has me using LabVIEW. I am trying to find a block ...
0
votes
0answers
94 views

Daisy chaining EV3 with RobotC

I'm trying to run EV3 programs with RobotC and trying run on EV3 Daisy Chaining. I have three independent EV3 bricks labelled A,B,C. I want, according to the color reading by the color sensor on ...
0
votes
0answers
36 views

Use of Mindsensors IMU with Labview

I thought someone could help me with a the Mindsensors AbsoluteIMU ACG and its use with the Lego Mindstorms NXT. Is it possible to use it with and get data out of it?
0
votes
0answers
42 views

How to transfer my F# exe file to NXT brick

I have developed a project in F# with MonoBrickFirmware library. I want to transfer the project to NXT brick, and run it.
1
vote
1answer
118 views

Execute program programmatically

I want to program our Ev3 for FLL (class assignment), and I want to use an object oriented approach in a very procedural environment. Is there a programmatic way to execute another program inside the ...
1
vote
2answers
151 views

Reading current motor speed, opOutput_Read

I'm trying to read current motor speed using direct command: Instruction opOutput_Read (LAYER, NO, *SPEED, *TACHO) Opcode 0xA8 Arguments (Data8) LAYER – Specify chain ...
1
vote
1answer
167 views

How to program light sensor to follow moving light using NXT

Cannot figure out how to simply program Lego Mindstorm NXT robot to follow another moving robot that has a bright LED light attached to it. Currently my programme looks like this:
2
votes
1answer
116 views

Trying to get a modified traffic signal challenge worked out

The challenge is for a robot to go around the perimeter of a rectangular field and execute 90 degree turns when it gets within 4.5 inches of a wall. Simultaneously, if the bot encounters a red flag, ...
1
vote
1answer
107 views

Lego EV3 - Get output device type, opOUTPUT_GET_TYPE

I would like to know what kind of motor (XL, L) is connected to EV3 output port (A|B|C|D). I need to use direct command: Instruction opOutput_Get_Type (LAYER, NO, *TYPE) Opcode ...
2
votes
1answer
124 views

EV3 RMIregulatedMotor Regulation Problems

I have problem with regulation of the motor when I control EV3 with Bluetooth. Here is the code: RemoteEV3 ev3 = new RemoteEV3("10.0.1.1"); ev3.setDefault(); RMIRegulatedMotor leftMotor = ...
3
votes
1answer
40 views

NXT brick not executing programs correctly

I have an issue that I am hoping someone might be able to resolve: We're using Mindstorms in the classroom as part of a STEM program and have one NXT brick that wont execute programs correctly. The ...
3
votes
2answers
584 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
1answer
103 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 ...
1
vote
1answer
88 views

Teleoperated arm trouble

I have built a robotic arm with the lego Mindstorms ev3. My goal is to control its motion via teleoperation, that is , to have a gyro sensor strapped onto my arm and have the robot mimick the up and ...
2
votes
1answer
58 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 ...
3
votes
2answers
72 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 ...
4
votes
1answer
323 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 ...
1
vote
1answer
641 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 ...
5
votes
1answer
172 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.
3
votes
2answers
425 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 ...
2
votes
1answer
313 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> ...
4
votes
2answers
364 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 ...
1
vote
3answers
533 views

My Blocks with return parameter

I have the retail EV3 kit and have created a function with in and out numeric parameters. While using the [in] params seem quite straight forward, it seems that I can only set the [out] param once. ...
4
votes
3answers
227 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 ...
2
votes
1answer
373 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
3answers
1k views

API for Android or iOS connecting to EV3 by bluetooth

There is official API for Windows, WindowsPhone8 and WinRT https://legoev3.codeplex.com/ it lets you connect to EV3 brick and control it remotely from your WindowsPhone. Are there any libraries ...
2
votes
2answers
674 views

EV3 Brick Error Symbols?

I am currently developing an EV3 robot that sorts colored technic beams. However, the brick will only run part of the program and then generate a strange error code on the brick's screen. The error ...
2
votes
1answer
408 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 ...
1
vote
1answer
582 views

RGB sensor HOWTO use?

I've got an RGB sensor (this one with the three LED thingies) and wonder how to access it using NXC. I know I can SetSensorColorFull(IN_1); and then access it using ReadSensorColorEx or, for ...
3
votes
1answer
67 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
543 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 ...
0
votes
1answer
143 views

Can Mindstorms EV3 communicate using protocol 802.15.4?

My aim is to make the robot communicate using protocol 802.15.4 through a USB dongle 802.15.4 over 6LoWPAN. The robot has to be able to get information from TelosB. I wonder whether this possibility ...
0
votes
1answer
73 views

I can’t run the NXT 1.0 program software on my Mac version 10.6

How do I fix this? I run the install program, restart my computer, go to the “Applications” folder and there is a folder named “LEGO MINDSTORMS NXT”. I open the folder and there are three “options”: a ...
1
vote
1answer
263 views

EV3 Event Delegation

My problem is that the robot, which should just remain in the program until the Escape Button is pressed, just stays in the while-loop. The current code looks like this: using System; using ...
1
vote
1answer
470 views

“The type or namespace name ”Brick“ could not be found” Xamarin Studio with MonoBrick

I managed to establish a wifi connection with the Ev3 Brick via WinSCD and am programming the Ev3 with XamarinStudio/Mono Develop(http://xamarin.com/studio "XamarinStudio"). My problem is that "The ...
0
votes
1answer
273 views

Guide me on how to use my Mindstorm RCX kit on OS X Mavericks

Any suggestions on how I can use my old RCX set on Mavericks? I have set up Xcode command line tools, and I am getting compiler errors while trying to download nqc through Macports. Even downloading ...
4
votes
3answers
945 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
2answers
220 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
1answer
697 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
2answers
2k 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 ...
5
votes
2answers
2k 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!