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5

If you wish to program the EV3 with Scratch, then check out this project on github: https://github.com/koen-dejonghe/ev3-scratch-helper-app This software is a so-called helper app, that interfaces between the Scratch 2.0 offline editor and the Lego Mindstorms EV3. The EV3 must be booted from Lejos (http://sourceforge.net/p/lejos/wiki/Home/), requires a ...


5

Yes, it is possible to pass the port number as a parameter to a sensor or motor block via data wire. It's just that it's manually selected by default. To change this, go to the port of the sensor or motor block, and select the top-most option which has the plug icon on it: It will then create a data port for which motor port you want to use: The same ...


4

I could not find this in the help file, but according to this thread "Another little known characteristic of MyBlocks is that they aren't re-entrant. No two copies of the same MyBlock can be running at the same time." I tried a few simple programs in EV3-G and confirmed that this is true. The order in which they run appears to be random.


4

To get the actual time of day, you can use the mindsensors.com Realtime Clock Sensor.


3

I think I'd use the ultrasound sensor instead of the touch sensor (or the brightness sensor with the light turned on in a dark tunnel). I haven't tried this but I'd worry about the touch sensor derailing or scratching the train. Otherwse, your system sounds pretty doable. The collision risk could be addressed by setting up the sensor a little further before ...


3

You can use the Bluetooth mailbox feature to pass messages back and forth between 2 NXTs. If you want to use sensors, you could use the HiTechnic NXT IRLink Sensor (NIL1046) and NXT IRReceiver Sensor (NIR1032).


3

This can usually be achieved on the EV3 with a bootable SD card - you would set that up with a new firmware image and a loader that copies it across to the brick. The leJOS team have ported their codebase to the EV3 - so with a bootable SD card you can indeed load a modified version of the firmware onto your EV3 brick. You can then use their WiFi stack to ...


2

I am working on a project called ev3dev that runs Debian on the EV3. We are not quite to the point that we support "all the Robot EV3 functionalities", but we are getting very close. We are also using a version 3.3.0 Linux kernel, which is more up to date than the other EV3 firmware projects that I know of (which use a 2.6.33 kernel). If you would like to ...


2

I think that it mean that the virtual machine running on the EV3 brick has encountered an unknown instruction. Perhaps your program has become corrupted or there is an block that is not configured correctly. I would copy and paste your blocks into a new program and see if it works. If it does not, start a new program from scratch or just copy a little bit ...


2

Since you are a C# pro, I would recommend MonoBrick. I know they have a plugin for Xamarin Studio/MonoDevelop that lets you do remote debugging. Not sure if they have one for Visual Studio yet.


2

Works for me if you set buffering to 0 and get rid of the newlines. import time # command to start motor on port A at speed 20 start_motor = '\x0C\x00\x00\x00\x80\x00\x00\xA4\x00\x01\x14\xA6\x00\x01' # command to stop motor on port A stop_motor = '\x09\x00\x01\x00\x80\x00\x00\xA3\x00\x01\x00' # send commands to EV3 via bluetooth with ...


2

I started coding using NXT software and later EV3 and lately I have switched to java using leJOS. EV3 software ( and NXT ) is great for quickly hacking your ideas but when things get ugly the graphical language doesn't help at all. Just watch what I needed to do to create a playable version of Pong for one player at ...


2

I got also the wheels and found it really interesting... so I wrote an article were I explain all the maths and show you how to build one yourself ( instruction attached ) http://thetechnicgear.com/2014/04/howto-build-3-wheels-holonomic-robot-using-lego/ The code is for EV3 software and I will surely rewrite it for leJOS ( despite there is a class that ...


2

No, EV3 MyBlocks cannot be recursive. If a MyBlock contains a copy of itself, then the following error will be produced upon compiling: For some reason, LEGO's programming software has become progressively less immediate about notifying you that this cannot be done. In EV3-G, it waits until compile to let you know that you can't do this. In NXT-G (the ...


2

I am currently maintaining my own fork of NQC for use on OpenBSD and OS X. As you have discovered, the recent compiler changes on OS X broke NQC in many places. Not to mention that the USB tower integration was pretty outdated. If you can compile it, it should work better than the ports version. AFAIK, I am now the de facto maintainer for NQC. (And may ...


2

Time is thought of as a sensor value, measured in seconds. The Timer sensor can be used directly, as part of a Wait For block, as part of a Loop block.


2

It is not possible to modify the properties of myBlock in the current version of EV3 SW. It is possible by tampering the block source files: create a copy of your *.ev3. Just in case rename *.ev3 to *.zip extract all files from the zip edit files as needed move changed files back into zip (Under Windows drag and drop to zip) rename *.zip to *.ev3 I ...


2

Checking the source code, it appears that the opOutput_Get_Type command is not implemented. In both links, it is mentioned in the comments, but there is nothing in the actual code. Unfortunately, I am not finding a different way to get this information.


2

Sadly, there isn't much info yet. Current options for audio are: USB Sound Card BlueZ 4/Pulseaudio 4 (BlueZ 5/Pulseaudio 5 supports A2DP only) The number of devices that have been tested and documented is extremely limited, but at least one has been confirmed to work. The non-bluetooth solutions that have been tested successfully are the following. ...


2

This is more of a LabView answer than a Mindstorms answer, but you should be able to create a SubVI that represents a task, and then you can place that in the main VI. This help document might be useful: http://zone.ni.com/reference/en-XX/help/372962A-01/lvnxt/creatingusingsubvi/


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

If you need to change something that is setup in the "My Block Builder" dialog box like the default value or min and max values for a slider, then yes, you need to create a new My Block. This is easy though. Just select everything in the existing My Block except for the Input Parameter block, the Output Parameter block and the Start block and then select ...


1

The main problems I see are the following: The value in the numRight variable is wrong for two reason: The 'right' sensor is not reseted at the proper time and you read the 'left' sensor value instead of the 'right'. The angle calculation is faulty The half rotation is performed in the wrong direction Here are my code comments: //Move forward until you ...


1

Disclaimer: I have never used the EV3 interface, only the text based programming languages for the NXT. Therefore I might be proven wrong. I need a reliable way to read the gyro sensor readings I think the gyro sensor should have come with the appropriate instructions to do that. If not, you can find many tutorials online, such as this: ...


1

To understand how to use the data, it help to understand how the color sensor works. Let's take a step back for a minute and have a look. The sensitive electrical component here is just a photodiode or phototransistor that lets us measure light intensity. If we turn all of the LEDs off we are just measuring ambient light. If we turn on just one of the LEDs ...


1

You can consider this the "official" answer based on the EV3 firmware source code. This file is used for scaling the values that you see in "Port View" on the EV3 brick itself. The NXT Light Sensor is defined in these two lines: 2 0 NXT-REFLECT 1 1 3 0 2 119 0x32 3372.0 445.0 0 100 0.0 100.0 20 0 pct 2 1 NXT-AMBIENT 1 1 3 0 2 119 0x30 3411.0 633.0 0 100 ...


1

Copied from Github: I haven't heard of anyone using a microphone yet, but you have a couple of options. 1) a USB sound card/microphone or 2) Bluetooth headset/hands-free device. The built-in speaker uses an alsa sound driver, so theoretically, it should work with any linux program. If you are looking at purchasing something USB, make sure it does not ...


1

Can I only set an [out] param once? Yes. You cannot tell it to be 2 different values at the same time. This applies to any block, not just the output block. Does setting the [out] param act like the "return" keyword? Not really. The return keyword in most (if not all) programming languages causes the function to exit, which is not the case here. ...


1

Here is an article that may be useful: http://botbench.com/blog/2014/05/11/omniwheel-article-in-dt-practice/



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