1. For downloading SimTools plugins you need a Download Package. Get it with virtual coins that you receive for forum activity or Buy Download Package - We have a zero Spam tolerance so read our forum rules first.

    Buy Now a Download Plan!
  2. Do not try to cheat our system and do not post an unnecessary amount of useless posts only to earn credits here. We have a zero spam tolerance policy and this will cause a ban of your user account. Otherwise we wish you a pleasant stay here! Read the forum rules
  3. We have a few rules which you need to read and accept before posting anything here! Following these rules will keep the forum clean and your stay pleasant. Do not follow these rules can lead to permanent exclusion from this website: Read the forum rules.
    Are you a company? Read our company rules

MWB 4 DOF Simulator

Discussion in 'DIY Motion Simulator Projects' started by MWB, Aug 29, 2016.

  1. MWB

    MWB Drive it like you stole it!!

    Joined:
    Jan 2, 2016
    Messages:
    131
    Occupation:
    Commissioning Engineer
    Location:
    U.K.
    Balance:
    424Coins
    Ratings:
    +146 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform, 4DOF, 6DOF
    Hi @Nick Moxley, I like what you have done. I may well be pinching you're idea :thumbs do you know the wattage of you're motors? and how have you found them?
  2. MWB

    MWB Drive it like you stole it!!

    Joined:
    Jan 2, 2016
    Messages:
    131
    Occupation:
    Commissioning Engineer
    Location:
    U.K.
    Balance:
    424Coins
    Ratings:
    +146 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform, 4DOF, 6DOF
    • Like Like x 4
    Last edited: Dec 28, 2016
  3. MWB

    MWB Drive it like you stole it!!

    Joined:
    Jan 2, 2016
    Messages:
    131
    Occupation:
    Commissioning Engineer
    Location:
    U.K.
    Balance:
    424Coins
    Ratings:
    +146 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform, 4DOF, 6DOF
    More motor testing

    • Like Like x 2
  4. MWB

    MWB Drive it like you stole it!!

    Joined:
    Jan 2, 2016
    Messages:
    131
    Occupation:
    Commissioning Engineer
    Location:
    U.K.
    Balance:
    424Coins
    Ratings:
    +146 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform, 4DOF, 6DOF
    • Like Like x 2
  5. MWB

    MWB Drive it like you stole it!!

    Joined:
    Jan 2, 2016
    Messages:
    131
    Occupation:
    Commissioning Engineer
    Location:
    U.K.
    Balance:
    424Coins
    Ratings:
    +146 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform, 4DOF, 6DOF
    Using Solid Works I started designing my rig.
    IMG_3483.JPG
    IMG_3484.JPG
    IMG_3485.JPG
    IMG_3489.JPG
    • Like Like x 5
  6. MWB

    MWB Drive it like you stole it!!

    Joined:
    Jan 2, 2016
    Messages:
    131
    Occupation:
    Commissioning Engineer
    Location:
    U.K.
    Balance:
    424Coins
    Ratings:
    +146 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform, 4DOF, 6DOF
    A lot of the builds on here seem to be using server power supply's, I been testing with a couple of old car battery's and an 11A 24v PSU (£10 from eBay) set to 26v as to trickle charge the battery's when in use and it seems to be ok. Got 1580A cold cranking from the battery's alone ⚡️
    • Creative Creative x 1
  7. OZHEAT

    OZHEAT Active Member

    Joined:
    Oct 26, 2015
    Messages:
    212
    Location:
    Australia
    Balance:
    2,449Coins
    Ratings:
    +104 / 6 / -0
    My Motion Simulator:
    3DOF, DC motor
    @MWB,
    Have you tested your design in solidworks to see if it will fall down?
    lt doesn't look constrained in all positions.

    Batteries are good but how you going to combat over draining and over charging the batteries?
  8. MWB

    MWB Drive it like you stole it!!

    Joined:
    Jan 2, 2016
    Messages:
    131
    Occupation:
    Commissioning Engineer
    Location:
    U.K.
    Balance:
    424Coins
    Ratings:
    +146 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform, 4DOF, 6DOF
    Hi @OZHEAT, yes I tested it in SW, took a bit of mucking around to get everything positioned correctly, but it seems stable now. Fingers crossed.
    My thinking on the battery's, is that in a car with the engine running the 12v car battery is allways being charged my the alternator and regulated to 14.6v, so you could say that with two battery's connected in series to get you're 24v you could charge them at 29.2v. This would need to be monitored. I have heard of car batteries exploding due to over charging, but I think the biggest danger is the production of hydrogen.



    I don't think this will be a problem for me as I'm only trickle charging the batteries at 26v, I did at one point crank that up to 28v and popped one of my IBT-2 boards (max volt 27v).
    See earlier in my thread.
    I had been testing for a couple of hours with two motors, the batteries were holding up pretty well still had 12.6 V on both and wasn't charging them at that point.
    May need to think about a ventilated box to contain an explosion if something did go wrong, but I think the risk is minimal, also in the video above, the battery cell tops are off, I've got them closed, and in a car the battery's always charging with the cells closed.
    Last edited: Dec 30, 2016
  9. MWB

    MWB Drive it like you stole it!!

    Joined:
    Jan 2, 2016
    Messages:
    131
    Occupation:
    Commissioning Engineer
    Location:
    U.K.
    Balance:
    424Coins
    Ratings:
    +146 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform, 4DOF, 6DOF
    Started mounting at couple IBT-2 in a box so that I could also mount fan's on the heatsinks
    IMG_3356.JPG
    IMG_3358.JPG
    IMG_3366.JPG
    IMG_3367.JPG
    IMG_3368.JPG IMG_3370.JPG
    • Like Like x 1
    • Creative Creative x 1
  10. MWB

    MWB Drive it like you stole it!!

    Joined:
    Jan 2, 2016
    Messages:
    131
    Occupation:
    Commissioning Engineer
    Location:
    U.K.
    Balance:
    424Coins
    Ratings:
    +146 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform, 4DOF, 6DOF
    Also got two motors connected to Dirt Rally via Simtools

    • Like Like x 3
  11. MWB

    MWB Drive it like you stole it!!

    Joined:
    Jan 2, 2016
    Messages:
    131
    Occupation:
    Commissioning Engineer
    Location:
    U.K.
    Balance:
    424Coins
    Ratings:
    +146 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform, 4DOF, 6DOF
    Hall affects pots turned up from Farnell today! :thumbs

    IMG_3934.JPG
    • Like Like x 4
  12. MWB

    MWB Drive it like you stole it!!

    Joined:
    Jan 2, 2016
    Messages:
    131
    Occupation:
    Commissioning Engineer
    Location:
    U.K.
    Balance:
    424Coins
    Ratings:
    +146 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform, 4DOF, 6DOF
    This is my my bucket seat, and my metal turned up so I've been busy Busy cutting, grinding, welding, filing. I'll pop up some pics later. IMG_3364.JPG
    • Like Like x 4
  13. MWB

    MWB Drive it like you stole it!!

    Joined:
    Jan 2, 2016
    Messages:
    131
    Occupation:
    Commissioning Engineer
    Location:
    U.K.
    Balance:
    424Coins
    Ratings:
    +146 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform, 4DOF, 6DOF
    Happy New Year everyone!
    • Like Like x 4
  14. MWB

    MWB Drive it like you stole it!!

    Joined:
    Jan 2, 2016
    Messages:
    131
    Occupation:
    Commissioning Engineer
    Location:
    U.K.
    Balance:
    424Coins
    Ratings:
    +146 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform, 4DOF, 6DOF
    Struggling with one of my motors so I decided to clean up the commutator. IMG_3941.JPG
    Gear box grease is pretty grim!!
    IMG_3942.JPG
    In order to get to the commutator, I needed to remove both brushes and modify a flat blade to get the two nuts off.
    IMG_3945.JPG
    Then the outer case of the motor could be removed. IMG_3949.JPG
    The commutator doesn't look to bad.
    IMG_3951.JPG
    But I cleaned it up anyway, using my drill and 1200 grit, then 2500 grit.
    IMG_3953.JPG
    Had one stubborn score! Little more to come off.
    IMG_3954.JPG
    All done!
    IMG_3955.JPG
    Just needed to scrape out and crap between the commutator tracks.
    IMG_3956.JPG
    Then just a good clean up to get rid of any carbon from the brushes and sand paper. I had buzzed everything out before and after with a ohm meter. Hope this works a little better now! I'll let you know how I get on.
    • Like Like x 2
    • Useful Useful x 1
  15. MWB

    MWB Drive it like you stole it!!

    Joined:
    Jan 2, 2016
    Messages:
    131
    Occupation:
    Commissioning Engineer
    Location:
    U.K.
    Balance:
    424Coins
    Ratings:
    +146 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform, 4DOF, 6DOF
    So the motor was I little better, but I still have the same problem, I think it's the IBT-2 motor controller cutting out, its meant to be good for 43A but I have my suspicions its not anywhere near that. I know that @SilentChill thinks there crap? Also in SMC3 if I set PWMmax to max will this unnecessarily over work the controller?
    • Agree Agree x 2
  16. Tim McGuire

    Tim McGuire "Forever a work in progress"

    Joined:
    Jul 26, 2015
    Messages:
    261
    Occupation:
    Electrical/Electronics Engineer
    Location:
    Canada
    Balance:
    2,071Coins
    Ratings:
    +312 / 1 / -0
    My Motion Simulator:
    3DOF, DC motor
    I'm not familiar with how the IBT-2 bridge works, but if you set PWMmax all the way up it's essentially telling your driver to turn the fets 100% on. This will trip the current limiters on the MMs on my sim, so I have mine set to 235, but this is only because my drivers are not large enough to drive the motor at 100% without going over rated current. If your motors stall current is less than the motor drivers maximum you shouldn't be having any problems though.

    you can check the stall current of your motors by following this procedure:
    https://www.xsimulator.net/community/faq/measuring-motor-stall-current.252/
    • Like Like x 1
  17. MWB

    MWB Drive it like you stole it!!

    Joined:
    Jan 2, 2016
    Messages:
    131
    Occupation:
    Commissioning Engineer
    Location:
    U.K.
    Balance:
    424Coins
    Ratings:
    +146 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform, 4DOF, 6DOF
    Hi @Tim McGuire, Thanks for the help! :thumbs
    I think I've worked out the stall current, correct me if I'm wrong!

    Measuring the ohms across the motor windings accurately will be impossible with a normal multi meter because the value will be to small so, applying a small voltage across the motor and measuring the current is the way to go, then using ohm law (V/IxR) to calculate the resistance. (Motor shouldn't turn when doing this)

    So at 2.9V I got 4A (V/A=R) 2.9/4=0.725

    The resistance across my motor windings is 0.725 ohms

    Motor is 24v so (V/R=A) 24/0.725=33.10

    So if I've done this correctly my stall current is 33.10A

    But I'm running the motors at 26V

    26/0.725= 35.86A
    • Like Like x 1
    • Creative Creative x 1
    Last edited: Jan 17, 2017
  18. Tim McGuire

    Tim McGuire "Forever a work in progress"

    Joined:
    Jul 26, 2015
    Messages:
    261
    Occupation:
    Electrical/Electronics Engineer
    Location:
    Canada
    Balance:
    2,071Coins
    Ratings:
    +312 / 1 / -0
    My Motion Simulator:
    3DOF, DC motor
    Cool! That seems like a reasonable value for a 24V motor to have. So I think your drivers should be able to handle it if they really are good for 43A. Do you have loads attached to them yet?
    • Like Like x 1
  19. MWB

    MWB Drive it like you stole it!!

    Joined:
    Jan 2, 2016
    Messages:
    131
    Occupation:
    Commissioning Engineer
    Location:
    U.K.
    Balance:
    424Coins
    Ratings:
    +146 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform, 4DOF, 6DOF
    I may need some refinement in my settings to squeeze the most out of my controllers. I think I'm unnecessarily pulling to much current through them.
  20. MWB

    MWB Drive it like you stole it!!

    Joined:
    Jan 2, 2016
    Messages:
    131
    Occupation:
    Commissioning Engineer
    Location:
    U.K.
    Balance:
    424Coins
    Ratings:
    +146 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino, Motion platform, 4DOF, 6DOF
    If that doesn't work, it's mm's! I gather there newer technology than the IBT-2. The power chip looks much bigger.