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MajorAlvega

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Everything posted by MajorAlvega

  1. MajorAlvega
    The PUP handset is not a HID device. But I think it is possible to create a driver that creates a HID device with it but that would depend on the operating system. And yes, the PUP hub can assume both roles (master and slave) at the same time device, that makes it very interesting when several devices are present (like several hubs and one handset joined in some sort of BT mesh).
  2. MajorAlvega
    Hi. I live near Lisbon. We are still waiting for an official LEGO shop in Portugal. Until that happens (probably after Finland wins the Eurovision festival and Hell freezes), best option in Lisbon is that shop on the post above. We also have 2 or 3 Toys R Us stores in Lisbon or nearby and a few "hipermarket" brands sell LEGO but just a few sets. The shop has a presence on facebook ("https://www.facebook.com/profile.php?id=116519548720655&ref=br_rs") so you might ask them for prices. Hope you enjoy Lisbon... Autumn arrived this week but weather is still warm.
  3. MajorAlvega
    Thanks. I also hope so. The Technic forum has a strong Technic community, it's nice but of course it really is Technic biased and I felt there was no space for MINDSTORMS to get noticed there, even worst for less known fields like WeDO. BOOST/Powered Up might change things a bit as more and more people start programming their LEGO sets, let's see.
  4. MajorAlvega
    There are two LEGO NFC/RFID devices (that I know of): - the Codatex RFID reader that was in fact sold as LEGO. It works with NXT but doesn't work with EV3 native firmware (EV3-G), you need LeJOS or RobotC or ev3dev linux (I wrote an ugly python script for ev3dev, https://github.com/JorgePe/CodatexRFID-ev3dev) - the LEGO DIMENSIONS Toy Pad, it has 3 NFC readers inside and can be used with ev3dev through USB, you can see a silly demo I wrote here: https://ofalcao.pt/blog/2017/ev3-minifig-inventory Non-LEGO devices can also be used but you then your only option is ev3dev. I used the Innovations ID-20 with a USB reader on my automatic turntable, it accepts the same 125 kHz cards/tags used by Codatex/LEGO RFID sensor. I'm not sure but I think I added a link to the code on the notes of the video I published here on the forum, it's very simple (most devices available for Raspberry Pi or Arduino are very easy to use in ev3dev). Also used a NFC device compatible with Mifare NFC tags (like the DIMENSIONS tags) but don't remember which, perhaps the PN532 for Arduino, with a USB FTDI cable to connect to the EV3 USB port.
  5. MajorAlvega
    Thanks for creating this new forum. Maybe it's time to get back to Eurobricks. https://www.eurobricks.com/forum/index.php?/forums/topic/141648-lego-laser-harp/ https://www.eurobricks.com/forum/index.php?/forums/topic/107133-wip-automatic-train-turntable-and-other-things/ https://www.eurobricks.com/forum/index.php?/forums/topic/102638-lego-wedo-with-linux-and-mindstorms-ev3/
  6. MajorAlvega
    You can use Scratch with BOOST. You need a computer with a custom USB dongle, the BLED112, or a Chromebook. And S2Bot: http://www.picaxe.com/LEGO-Boost/ Scratch is visually similar to the LEGO BOOST App (both concepts were born at MIT). And if you are the geek type, you can use some of the projects that have born after we started to reverse engineering the BOOST: https://github.com/JorgePe/BOOSTreveng Side note: you can also use the LEGO Dimensions without a "computer". Just not with the LEGO game :)
  7. MajorAlvega
    First link you gave for those AA 1.5 LiPo batteries states that "Maximum output current: Less than 1A". That's not good If you plan to use the several of the large EV3 motors at the same time. Also 400 mAh capacity is very low, your robots will have short autonomy. And you still have to take batteries out to recharge (or at least open the robot and plug 6 USB cables on it) - why don't you just use common NiMH batteries? The total voltage isn't so important.
  8. MajorAlvega
    A diode conducts electricity but it also generates heat while doing it. Each diode as a drop voltage, the 1N5401 voltage is between 0.6 Volt and 0.8 Volt (it drops more with more current). So if you use 2 fake bateries with diodes of this type and one shunt (a fake batery without diode) and 3x 14500 batteries @ 4.0 Volt each, you will get 3x4 - 2x 0.7 = 10.6 Volt. Test it for a minute or two and see if it gets to hot inside the Power Functions box. With normal Power Functions M or L motors it will not.
  9. MajorAlvega
    Each 1N5401 diode drops 0.6 to 0.8 Volt (depends on current). I usually use 2 diodes and one shunt so 1.2 to 1.6 Volt. If you have enough diodes you can use a pair for each fake battery, reverted, so you don't need to care about polarity when inserting on the battery box. Take care with heat - 0.8 Volt at 3 Ampere means 2.4 Watt on each diode. Not dangerous for short races but not neglectable.
  10. MajorAlvega
    I made them myself - just wrap tin foil around each diode anode/katode, you can use something like the body of a plastic pen to give it more strength: Dummy AA battery with diode by Jorge Pereira, on Flickr The batteries on my photos look pretty ugly but after 2 or 3 attempts you'll have something decent. If you just want a fake battery without diode just wrap enough tin foil around a stick of hot glue or a pencil. For 3A diodes I used common 1N5401.
  11. MajorAlvega
    You are confusing battery types. 18650 is not AA size, is much bigger. AA size compatible LiIon batteries are the 14500. These are rated for much lower mAh (I've been using 600 mAh, I know there are some up to 900 mAh, not more - even if some sites announce more, don't believe). Both 14500 and 18650 batteries are LiIon, not LiPo. They have very high discharge rates - the 14500 that I use have internal protection that cuts at 4A, I think - that's good to use with the SBrick. But a few models don't have internal protection - and that is very dangerous. You need a proper charger - common NiMH chargers don't work but there are some models that can charge both NiMh and LiIon. I've used 14500 batteries with LEGO a few times. Here you can see my 42965 RC Tracked Racer running with 3x14500 - that's 12.6 Volt when full charged so I use some dummy batteries with diodes inside to reduce to a safer value, around 11 Volt:
  12. MajorAlvega
    If your Android has IR (some have) there are apps that can use LIRC configuration files to control Power Functions IR. It is also possible with IRDroid and other Audio-to-IR gadgets. I've done it in the past with Android 4 but never achieve it again with Android 5, think that something must have been changed in API used by those apps.
  13. MajorAlvega
    Seems a little bit faster. But still having problems with multi-paged topics (at least with Technic forum), seems to stop while loading. Firefox 51.0.1 (64-bit) with Ubuntu 16.10
  14. MajorAlvega
    "It seems that the battery boxes (AA or AAA) are the only official Lego components where the 2-wire-to-4-wire connection is made." As far as I know, yes. If you do need to use a LEGO switch, wiring a custom switch in the same way it is done in the battery boxes is no option. I guess using a Mindstorms is overkill? But I think you can do the same "left-center-right" movement with an ordinary motor and some clever mechanical setup, like Isogawa or other master builders (look for stepper motor).
  15. MajorAlvega
    The servo position is proportional to the voltage at C1/C2. It's not always 0 or 9V - with the LiPo battery it goes from 0 to "9V" in 6 or 7 steps (both directions). The AA and AAA boxes are wired in a way that C1 and C2 are connected the way you observed. The empty battery box trick is the only one I know for a manual switch. Using a Power Functions remote is not an option?
  16. MajorAlvega
    Yes, that makes sense. My cheap back surface mirrors tend to distort the beam and/or create optic effects.
  17. MajorAlvega
    The 20193 mirror is not so bad. In fact, it reflects my cheap red laser better than a real (also cheap) mirror I used: Your green laser seems to be better focused than mine red laser and also more powerfull so you may like this LEGO mirrors. They were not cheap a year ago but lately the price seems to be dropping a bit at bricklink. If you want to take pictures of the beam add some smoke or fog. There are some cheap USB water foggers that do the trick for short paths.
  18. MajorAlvega
    OK. Be carefull not to short the + to the - The LEGO battery has an internal protection to prevent overcurrent but just in case test it with used alcaline batteries.
  19. MajorAlvega
    Are you familiar with a soldering iron? If you bypass the diode bridge and revert one of the LEDs, one of the LEDs will light up with positive/direct voltage and the other with negative/reverse voltage. To bypass the bridge you may solder one of the ~ to the + and the other ~ to the -
  20. MajorAlvega
    Great, someone is using my ugly code :) You are right about the regular train remote: it doesn't use Power Functions ComboPWM protocol, it uses ComboDirectMode. This mode sends a command to the IR Receiver and it keeps running these command until it receives another or until you press the small red buttons and reset the receiver. I only tried ComboPWM, sorry. About the short range, that's the biggest problem I see when using IR. We can try to "focus" the IR beam but only when your device is stationery, not an option for trains. Only solution is using radio. Nowadays everybody is crazy about Bluetooth 4 LE (SBrick, WeDo 2.0, Power Functions 2.0 when available) but LEGO also had the CyberMaster, you can use a serial port to send RCX byte-code commands through radio to it.
  21. MajorAlvega
    if you're still considering ev3dev, I've got python working with the IRLink in ComboPWM mode: http://ofalcao.pt/blog/2016/ev3dev-using-irlink-with-python It's just an ugly conversion to python of parts of the code I found from Mike Hatton (“Parax”), Xander Soldaat and Lawrie Griffiths on GitHub, RobotC forum and LeJOS forum but it's a good start.
  22. MajorAlvega
    For small or conventional projects I think there is no benefit at all - the learning curve is to expensive. The real benefit is when you need to do something that is not possible with EV3-G or it might become to complex to handle (like when you find you have to much blocks in your EV3-G code). Image recognition (like OpenCV) and other AI use cases are possible in ev3dev because most (Debian linux) libraries are already available for the language you like (C, Java, Python, R, javascript...). And extended hardware support is also nice - you want to interface with your Domotics system, with your old plotter, with your GPS... you probably can. Of course, it's very nerd/geek. But hey... we are adults working with LEGO, how more nerd/geek can it be?
  23. MajorAlvega
    Yes, the Motors multiplexer work in a similar way. But I have none, somehow I never got interested on it, I think mostly because it requires an external power supply - for some purposes that might actually be a big advantage. The few times I needed more than 4 motors I opted for a different approach (a WeDo USB Hub gives me two more weak PF motors with no extra battery, SBrick gives me up to four strong PF motors with extra battery, IR Link is also an option for PF motors and for non-LEGO motors a USB relay card or a USB servo controller can give me almost an unlimited number of motors). There's also a small limitation, at least with ev3dev: "it does not support all of the possible functions of the tacho-motor class (...) The NxtMMX does not have a way to monitor the duty cycle of the motor." It isn't a big limitation and honestly I don't know if in EV3-G it makes any difference at all (I must be the only EV3 owner in the world that doesn't use EV3-G). ev3dev is very powerful environment but it can also be a shock for the beginner since it lacks organized documentation and it requires some previous command line experience. You need to dig a lot at before gaining some confidence but a patient man like you, who cuts hundreds of rubber pads for your own custom tank tracks, seems a proper candidate to master it ;)
  24. MajorAlvega
    Hi oracid. Thanks! I'm using Mindsensors' EV3 Sensor Multiplexer for EV3 or NXT. It is a 3-to-1 input multiplexer that works with most (if not all) EV3 sensors. I've never used with native EV3-G language but I believe it is just a question of installing a driver from Mindsensors to get a new kind of EV3-G block. I'm using ev3dev (Debian linux for EV3) and it's just "Plug and Play" since by default ev3dev initializes each new input port to work with Color Sensors. For each MUX I get 3 input ports so as I'm using 2 MUX I get 6 ports (and loose 2 so I really gain only 4 ports). I'm not sure but I don't think it is possible to "daisy chain" to get extra ports, so the limit for one EV3 is (probably) 4 MUX which gives a total of 12 sensors. Not bad and less expensive than using 3 EV3 together :) Mindsensors has european distributors. The french one was very fast and has also many other robot-related products.
  25. MajorAlvega
    Thanks. The grey one is rather old (6228b) but the purple one (13392pb02) is from last year set '41072 - Naida's Spa Secret', there's a simillar one (13392pb01) on current year sets.
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