Questions tagged [ev3]

EV3 is the current generation of LEGO MINDSTORMS, released in 2013.

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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 ...
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1answer
3k views

Can you extract a program from the EV3 brick to the computer?

As part of an assignment, I made a program for my EV3, but however my computer automatically restarted, so I lost that program. I need to show the program! However, the program is still in my brick. ...
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Why I get this “message unable to compile some documents for deployment ev3”?

I have a LEGO Mindstorms EV3 program that I was working on for a long time but recently and suddenly when I try to download the program the software displays the following message: "unable to ...
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274 views

EV3 low battery communicate right after startup

I just bought EV3 and started having battery problems. I am using 6 NiMH 1.5V batteries for my EV3. They lasted for around 10 minutes of work and went flat (that's what EV3 kept saying but the ...
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1answer
88 views

How to use the direct command to make ev3 motor backward?

I write the java language. I use ev3 direct command make ev3 motor to run, example: "opOUTPUT_POWER,LC0(0),LC0(0x01),LC0(20), opOUTPUT_START,LC0(0),LC0(0x01)" In this case, the power is 20 so I ...
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1answer
834 views

Mindstorm EV3 no longer recognises SD card

I followed the instructions to install leJOS on an SD card, to get Java support for the Mindstorms EV3 brio. The brick detected the leJOS files and processed the whole installation procedure ...
2
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1answer
519 views

What is a better algorithm for wall following with an ultrasonic sensor?

This wall following algorithm uses the ultrasonic sensor. It has a horrible worst case behavior. Place the robot about 3 cm too far from the wall. Instead of moving closer to the wall, the robot ...
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7answers
12k views

Direct control of EV3

I need to control a car with an EV3 brick. I want to control it remotely. The trouble is, I'm using an education set so I don't have the remote. What means of controlling it remotely could I use? I ...
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LEGO Mindstorms Spik3r won't move

I built my Spik3r as usual, but it wouldn't run when I tried to program it. I checked the wheels and the legs and everything seemed fine. I even looked back in the instructions, and redid it. It still ...
5
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1answer
574 views

How to pause, and restart (without resetting), a timer block - ev3

We're trying to pause the timer block, and then have it restart at the same time where it left off. By using the touch sensor in a loop before our timer code we were able to get the text output to ...
4
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1answer
157 views

LEGO MINDSTORMS EV3 Can't find MyData Block

While going through the challenges of the Gyro Sensor Investigation I came upon the issue that I do not have the MyData Block (It's a dark blue block with a graph on it) on the coding program. Could ...
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EV3 Home edition for mac missing import block option

I'm running EV3 HE 1.3.1 on mac Sierra 10.12.6, and I'm unable to import the ultrasonic sensor. When I open tools -> import block -> browse, the open button is always disabled, it does not allow me to ...
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1answer
150 views

Do we need WiFi Dongle to install Scratch on EV3

I was wondering if I can install Scratch program on EV3 brick without the wifi dongle. Appreciate any insight here.
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3answers
374 views

Why won't the loop block in my EV3 program stop?

I am building a robotic hand, and I programmed the finger to close when the touch sensor is pressed, and release when the touch sensor is released. It did that with a loop block - but when I ran ...
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0answers
260 views

Why can't I install the NXT software?

I just got an Mindstorms EV3 for Christmas, and learned that you can have the NXT communicate with the EV3 in the NXT software. I tried to install the NXT software on my Mac, but all that happens is a ...
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653 views

Ev3 spik3r mission 2 doesn't move

So I was building Spik3r and I thought I got mission 2 completed. Wheels are turning, legs are moving but the robot just does not move. It looks like the small wheels should be moving the robot but ...
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1answer
1k views

Slow down the mindstorms EV3 motor so target position is not overshot

I have Debian jesse installed on a mindstorms EV3 and I'm using the ev3.lego library: https://github.com/topikachu/python-ev3 I want to be able to slow down the motor as it reaches its target ...
4
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1answer
403 views

What is the LEGO EV3 rpf file?

I read the LEGO Mindstorms EV3 Communication Developer Kit's document. I have a question in 4.2.1 (Start program “Demo” on EV3 brick) it is mentioned "The file-extension is "rpf" and NOT "rbf", so ...
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1answer
1k 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?
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491 views

Installed EV3 software on Win 8 and it won't load

EV3 software used to work on my laptop. Now it does not load any more. When I double click on the LEGO Mindstorms icon. It starts the procedure of loading the software. Then it stuck there and won'...
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2answers
2k views

What are the differences between NiMH and Alkaline batteries for the EV3?

Currently I am using six rechargeable batteries for my Lego Mindstorms EV3. A few seconds after I start a motor the EV3 gives a notification that that the battery is low. I know that good batteries ...
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1answer
1k views

EV3 with NiMH batteries

Could I use 6 NiMH 1.2V batteries and keep pressed the small black circle in the battery compartment in order to adjust the battery gauge and low battery alarm?
6
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1answer
167 views

Colored balls detectable by EV3 color sensor

I'm looking for large balls in standard Lego colors that are detectable by the EV3 color scanner. So black, white, green, brown, yellow and blue and between 5 and 10 cm. I'm aware of the Duplo balls:...
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1answer
57 views

Mindstorms program - myblocks that work fine when run individually but when executed as part of a larger program, break

We have a line following myblock, which follows the line perfectly if it runs alone. However, if we include it as a block as part of a larger program, it goes haywire when it gets to that step and ...
3
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1answer
192 views

EV3 Rapt3r's head cable interfering with slithering

My Rapt3r is working great, except that the cable that goes from the head to the "Intelligent Brick" physically interferes with the slithering on the side on which it is plugged (port 4). Physically ...
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2answers
736 views

“Unable to compile” error code with LEGO EV3 Arm Robot Program

Does anyone know how to fix this error with my LEGO EV3 program? Unable to compile some documents for deployment: Program.ev3p: Use of a block which no longer exists. INI.ev3p: A My Block cannot ...
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3answers
8k 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 ...
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2answers
2k views

Sort the program list on EV3

When uploading a project to the EV3 brick, is there a way to control the sorting order of the programs on the brick? E.g: Prog_1 Prog_2 Prog_3 ... When playing a robot match in FLL one often needs ...
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1answer
79 views

Why do two EV3 bricks have different power outputs?

I have two identical box designs with EV3 bricks. When I upload the same programs to both, one moves about twice as fast as the other. Is there a reason that this might be happening? Is there ...
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1answer
371 views

EV3 Installation failure on OSX El Capitan 10.11.3

Hi This is the first time I've tried to use EV3 software since upgrading to El Capitan. Before then, it worked perfectly. When I tried to launch the application a message pops up saying it has ...
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1answer
353 views

List of parts to buy for to “upgrade” existing Mindstorms NXT 1.0 to Mindstorms EV3 set?

Is there a list of parts available I need to buy to "upgrade" an existing Mindstorms NXT 1.0 (8527) set to a Mindstorms EV3 set?
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1answer
776 views

How to make Lego Mindstorms EV3 robot go in reverse when move steering input comes from proximity sensor

I saw an program on the Lego Education page which makes a Lego Mindstorms EV3 robot gradually slow down as it approaches a wall. The info from the proximity sensor is used as the direct wire input of ...
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2answers
5k views

Is the LEGO BOOST kit compatible with EV3 or PowerFunctions motors and sensors?

I'm curious if I can use my existing EV3 and/or PowerFunctions motors to extend the functionality of my LEGO BOOST set. Is this possible?
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3answers
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Does the Mindstorms EV3 software work on macOS Sierra?

I guess this is a continuation of these two questions: Does the Mindstorms EV3 software run on OS X El Capitan? Is the LEGO Midstorms EV3 software compatible with OS X yosemite? macOS Sierra was ...
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1answer
890 views

Can't create block: “Use of a block which no longer exists”

Unable to compile some documents for deployment: Program.ev3p: Use of a block which no longer exists. PutInRange.ev3p The block i want to make. It will put a input value inside a given range. When i ...
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1answer
229 views

Is code written for NXT bricks compatible with EV3 brick (for Johnny 5 building)?

My son is mad on the robot from Short Circuit (Johnny 5) and I want to build robots with him. We have a copy of Daniele Benedettelli's "Creating Cool Mindstorms NXT Robots" and I was planning to start ...
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1answer
2k views

How do I have an else in conjunction with an if statement with two conditions?

I can't find a way to emulate an AND statement in a switch statement: if (angle >= 10 and angle <= 30) ;// do smth else ; // this is what I want Until now, I just nested two if ...
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1answer
6k views

EV3 brick cannot connect my to computer

I can't connect my brick to my computer. It keeps saying it can't communicate with the brick. My brick has no firmware. My friend said to change the USB cable but it still doesn't work. I can't ...
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1answer
2k views

Is it possible to fix a broken EV3 Port?

I have an EV3 running RobotC version 4.55. The medium motor connected to Port A does not run, but if I connect it to another port (B,C,or D) it works. I tested it manually through the EV3 motor tab ...
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3answers
9k views

How can I use multiple switch options in Lego Mindstorms EV3 software?

What I see is just a simple if/then/else. What I am looking for is to be able to add multiple options, more than yes/no. I use a motor as a switcher, so I rotate it to some position and measure its ...
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1answer
891 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 ...
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0answers
320 views

Is there an leJOS simulator for EV3?

I found this but this seems to be using their own library to control the EV3.
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1answer
654 views

Lego Mindstorms EV3: programming language recommendation

I am planning to build an autonomous car in LEGO Mindstorms that will use ultrasonic or infrared sensors and in the future also a camera for line tracking. Currently I construct my programs using the ...
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0answers
821 views

LEGO Mindstorms EV3: Camera recommendation for lane tracking

I am planning to build an autonomous car in LEGO Mindstorms that will use ultrasonic or infrared sensors for collision avoidance and in the future also a camera for line tracking. I am now wondering ...
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1answer
421 views

LEGO EV3 on Chromebooks

I teach two LEGO robotics classes in middle school and in one of my classes I am using EV3 and in the other NXT. I was able to have these classes because of the Chromebook app, but the problem I am ...
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1answer
531 views

Does the Lego Mindstorms EV3 software work on macOS High Sierra?

Will there be issues with the software, or will it work properly on macOS High Sierra? My Mac: Retina MacBook Pro 13", Early 2015
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1answer
210 views

Why does my EV3 not have data logging in Brick App menu?

I recently purchased a 45544 Educator Mindstorms product. In working through tutorials. I am at section on data logging, but my Brick Apps menu stops at Brick Program. Data Logging is not on menu My ...
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2answers
150 views

Programming to get data

I am using EV3 with Linux V1.09 and I am doing a project in which I want to send the sensor data from the EV3 to a remote web server using POST method - is this possible?
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1answer
199 views

EV3 motor control proportional to another motor when more than two motors

From what I understand, in EV3-g you can use "move steering" or "move tank" blocks to regulate two motors proportionally to each other as they have a built-in PID controller to do that. If one motor ...
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1answer
686 views

LEGO EV3 I2C Compatibility

I'm having difficulties with communication between the EV3 and Arduino boards. Does anyone know if the EV3 is really I2C compatible, or is it just close enough? Background: I can get the EV3 to ...