Questions tagged [ev3]

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

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1answer
151 views

Why is the EV3 Ultrasonic Sensor (45504) out of stock?

The EV3 Ultrasonic Sensor (45504) has been out of stock for a long time. Is the sensor discontinued due to an accuracy problem? Is there an alternate version of "Gyro Boy" that works without the ...
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0answers
46 views

online ev3 robot with laser tag

I made these EV3 robots that move like a player avatar in an FPS computer game and want to set up some of them in a room for people to play with by remote control over the internet. Youtube video of ...
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4answers
9k 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 ...
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2answers
258 views

The center “ok” button does not work

My son has Lego Mindstorms EV3. The brick turns on when he pushes the center ok button, but he can't use it in the menu. What's the problem?
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36 views

T-R3X the look My Block problems [duplicate]

OK I am making the look My block for the T-R3X program but there is this block which don't know how to make at the end of the diagram in the book.
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0answers
45 views

how to send direct command to ev3 brick

I am new to ev3 python but am working on a project. I was reading about NXT-python that " It works by sending the direct commands detailed in LEGO's "Blue-tooth Development Kit" to the NXT brick" I ...
14
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2answers
7k views

Export Lego Mindstorms Code

I was wondering if it was possible in any way to see the actual code that is generated by the Lego Mindstorms IDE. I know there isn't a direct 'export to code' option within the tool but I wondered ...
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0answers
14 views

changing ev3p file back into an ev3 project file

how do I change an ev3p file into an ev3 project file. Everytime that I click on the ev3p file to open it, it turns up as text in notepad.
0
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1answer
33 views

Is there a way to restart a program with EV3?

I've got a program with a code lock, and I would like the program to restart when you enter the incorrect code. Does anyone know of a way to do that?
8
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1answer
243 views

How can body segments be moved to precise angles in snake robot?

I want to create an EV3 robot similar to this: I've glanced at the mentioned papers. To me it seems that some simpler equations to govern the motors will work also. I have 9 segments, articulated by ...
2
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2answers
15k views

Code for PID for EV3-g

I want to use PID for my Ev3. I used PID for NXT-G before, but I have never used EV3-G before and don't know how to get PID. Could someone please post a screen shot of the code or upload the file?
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1answer
91 views

Run Code From PC

https://www.ev3dev.org/projects/2014/05/09/Python-Rubiks-Cube-Solver/ The other one gives a solution in around 20 steps, but takes around 500 MB of memory, so I need to run it on a computer How do I ...
5
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1answer
95 views

How to mirror an EV3 motor?

I want to get one EV3 large motor to copy the other. So if I move one half a rotation the other copies.
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2answers
218 views

Is EV3 Device Manager still active?

Link to https://ev3manager.education.lego.com/ is broken - will this be fixed?
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0answers
46 views

What does this error symbol on the EV3 mean?

I get this error image pop up when I power on my EV3. What does it mean? Also, is there a list of different error codes anywhere, I looked in the User Manual and I could not see anything. Cheers!
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2answers
385 views

Is the NXT forward compatible with EV3 sensors and motors?

Is it possible to use EV3 sensors and motors with the NXT intelligent brick? I've read that the EV3 is backward compatible with NXT motors and sensors, but does vice versa work as well? Is the NXT ...
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0answers
37 views

The HiTechnic Color sensor is not detected in the port view in lab view

When I inserted the HiTechnic Color Sensor Block into the Ev3, the Ev3 detected the color sensor. But in my Mindstorms lab view, the HiTechnic color sensor does not appear on the port control. Can ...
2
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1answer
49 views

Stuck on “Installing rootfs” when installing leJOS on the brick

When following the instructions for creating an SD card with leJOS, the brick freezes when it comes to the screen “Installing rootfs.” I'm using a new 32 GB SanDisk SD card. I've confirmed that I'm ...
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5answers
1k views

How can I make my robot heavier?

I'm building a 3kg LEGO EV3 sumo robot and I need to make it as small as possible. Which LEGO items do you recommend to add more weight on it? (tires, plates, wheels, blocks, minifigs etc.)
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1answer
66 views

How to make of point coordinate system for EV3

I'm trying to make a internal coordinate system for an EV3 Python project I'm doing, but at a complete loss on how to do it. It needs to keep track of how it moves (with wheels) in an X, Y coordinate ...
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5answers
9k 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?
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2answers
95 views

What does this symbol on the EV3 Brick mean?

I can’t figure out how to get my R3PTAR to open and close it’s mouth to bite. I keep getting this symbol. What does it mean?
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38 views

EV3 Brick is Stuck on Red

The EV3 brick started by flashing red. Then started where it is stuck on two red buttons. Have changed batteries, and manual reset with no change.
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1answer
42 views

Looking for custom EV3 block to control LEDs independently

The EV3 brick has 2 LED sets, one on the left side of the button panel and one on the right. Software such as python for ev3dev let's you control them both individually, the normal EV3-G LED block ...
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0answers
43 views

Using switch block with Hitechnic color block

Can I compare the Hitechnic block --> measure --> color output in a switch block? For example, if the Hitechnic color sensor is seeing black, then do something, else do another thing. If not, then how ...
2
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2answers
113 views

Seeking HiTechnic Color Sensor V2 control block for EV3-G

I'm looking for the EV3-G control block for the HiTechnic Color Sensor V2, previously distributed by HiTechnic (https://www.hitechnic.com/cgi-bin/commerce.cgi?key=NCO1038&preadd=action), ...
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1answer
74 views

Anyone have the control block for the hitechnic color sensors?

I'm just wondering if anyone has a copy of the control block for the hitechnic color sensor v2? I'll take a v1 if you have that because I'm desperate at this point. The downloads page for it is down ...
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1answer
131 views

Why does the Gyro Sensor not work correctly in Virtual Robotics Toolkit?

I somehow found out about Virtual Robotics Toolkit and when I did, I decided that it would be great software to use for Lego League. Later in my research, I found that it automatically had the newest ...
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2answers
75 views

Can't link variable inside a switch when creating a new block

I have a problem when connecting the variable (from the create a block) to a variable in the function because it's inside a switch. How can I link them? I want to connect the variable to each (20) in ...
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0answers
38 views

Improving EV3 Screen Readability

I often have a hard time reading the EV3’s LCD display. I presume that I’m not the only one who has experienced this issue. Is there a way to improve its readability? For example, are there any good ...
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2answers
52 views

Color sensor reliable?

I am experimenting with the light sensor shipped within the mindstorms ev3 package. My Problem is that the bot is standing quiet at one place. Each value returned by sensor is different, although the ...
2
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1answer
63 views

Two motors are driven forward, why are they rotating in different directions?

I have the Lego Mindstorms EV3 Pack and built a simple car with 3 wheels. The back whels are motorized. When I run the following code: Motor.A.backward(); Motor.D.Backward(); both motors are ...
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1answer
90 views

Using two color sensors simultaneously

I am new to the world of robotics, and I'm preparing a new project with my students. Our goal is to make a self driving robot that can read colored signs from the road in order to turn right or left a ...
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1answer
45 views

LEGO Mindstorm EV3 Line-With-Gaps Follower? [Robotc]

Trying to create an algorithm / code in order to get my robot to follow a track which it currently can do, using a color sensor and following the inside edge. So I'm wondering how to transition to the ...
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2answers
67 views

Buy the complete EV3 set or only the brick?

I have an old NXT (or NXT 2.0, do not remember exactly) bought I think in 2007. I would like to upgrade to EV3, but I am not sure if I should buy the complete set or only the central brick. Is there ...
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0answers
50 views

EV3 Spinner factory not moving in the right order

We've built a spinner factory going by the original instructions in the Lego Mindstorms EV3 Education Software, and downloaded the program for it onto the bricks, the Spinner factory moves around, the ...
7
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1answer
743 views

Understanding the makeup of an XML .ev3p file

When you unzip an .ev3 program, there are many txt and xml files that are inside. In particular, there is an xml file produced with the filename extension .ev3p, which seems to contain program ...
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1answer
55 views

How to connect an NXT brick to the LEGO programmer application on an iPad?

Can you connect a NXT brick to an iPad via either USB cable or bluetooth? For me neither seem to work even though the EV3 brick (and the LEGO programmer application) should be backwards compatible. ...
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0answers
49 views

Read power usage and respond when motor is straining

Is there a way to know if the drive wheels are "straining", like when locked up with an opposing bot? This is for a Lego sumo bot using the Lego Mindstorms Education EV3 Core Set (EV3 Large Motor ...
7
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3answers
2k views

Lego Mindstorms Ev3 home edition on Mac OS Mojave bug - bricks sometimes go blank

I have a fresh install of Mojave and of Mindstorms Ev3 home edition. It seems to work fine but then randomly all the information disappears from the blocks at the bottom of the screen, and sometimes ...
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3answers
129 views

EV3 Multiple conditions: wait sensor activation for N seconds or

How to program EV3 to wait for a sensor activation for at most X seconds? If the sensor is activated in the given time, begin sequence B. If it is not activated in X seconds, begin sequence A. ...
2
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0answers
121 views

How many rotations or degrees do you need to turn your robot?

I have an EV3 Home edition. I have made a tribot. Two main motors for the wheels and a caster in the back. To complete a full turn in place I need to set the rotations to 2.32 or 835 degrees. Does ...
6
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3answers
5k views

EV3 screen stuck at “Starting…”

After I turn the device on, its screen is stuck at "starting..." for a long time. It hasn't change into the regular screen, and the light behind the button was still red (didn't become green). Is ...
4
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1answer
730 views

How to install Firmware 1.10E on an EV3 home/retail edition brick

If and how can you install firmware 1.10E on an EV3 brick from an home/retail edition set (instead of an education set)? Updates 1.0E9 are only recognized from the Mindstorm software, also with ...
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0answers
73 views

Function in EV3 Basic

I have been programming in basic for ~30 years. I want a translation of the following code into EV3 Basic: function index( x , y ) return x + y * ( maxx , + 1 end function sub look for i = 0 ...
3
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2answers
298 views

How To Plug Detected Light Values into Variables and Still be Usable in Programs in EV3-G

I've seen teams, mostly in the world festival do this, and what they do is they program the robot so that when a brick button is pressed, the robot detects a value (usually RLI) and it is used later ...
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0answers
106 views

EV3 Brick and Commander app bluetooth disconnecting

On OSX on an iPad, we're having an issue with the EV3 Brick and Commander app bluetooth connection constantly disconnecting. The brick just stops responding, so we turn the brick off to disconnect and ...
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1answer
113 views

How I can program a solar panel heliostat? [closed]

I want to make a program for an EV3 solar heliostat. It consists of two motors and a color sensor. I want it to follow the light. The station is fixed. EV3SolarStation pdf
3
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1answer
960 views

EV3 motor TACHO signal connection. Hardware schematic questions

I'm trying to understand EV3 motor TACHO signals circuit on the EV3 hardware schematic. Please look at the image below. There are two things I can't understand: On the left side, the TACHOA0 input ...
3
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1answer
52 views

How do I delete custom images I made in my computer?

I created a custom image for a test, and everytime I download the program to my brick, the image shows up in the folder despite me not using a display program. How do I fix this?