1. Do not share user accounts! Any account that is shared by another person will be blocked and closed. This means: we will close not only the account that is shared, but also the main account of the user who uses another person's account. We have the ability to detect account sharing, so please do not try to cheat the system. This action will take place on 04/18/2023. Read all forum rules.
    Dismiss Notice
  2. 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!
  3. 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
  4. 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

First Motion Sim - 2DOF Seat Mover With DIY Peripherals

Discussion in 'DIY Motion Simulator Projects' started by CBC_North, Jul 10, 2018.

  1. CBC_North

    CBC_North Member

    Joined:
    Jun 29, 2018
    Messages:
    40
    Occupation:
    Computer Engineer
    Location:
    Ottawa, Canada
    Balance:
    333Coins
    Ratings:
    +34 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino
    Edit: Finished simulator video first.



    ------------------------------------------------------------------

    Starting this build log to track progress on my first motion simulator. Will feature:
    - 2DOF seat mover (Leaning towards shoulder mounted now but also looking at compact desk racer)
    - 3 bass shaker channels running simvibe
    - DIY peripherals - Sequential shifter, handbrake, pedals

    I currently have an 80% functional sim without motion. Based it off the wooden "Death Mobile" design over at ISRTV. Really like what the bass shakers added using simvibe but instantly wanted more feedback. This got me looking for motion sims and ultimately subscribed to this forum. Tons of great inspiration here and I'm going to be taking heavily from it for my design.

    Picture of my current rig below. More details of what I currently have and my plans will come later...

    Current_rig.jpg
    • Like Like x 4
    Last edited: Mar 30, 2019
  2. Zeraxx

    Zeraxx Member

    Joined:
    Jun 28, 2018
    Messages:
    38
    Balance:
    188Coins
    Ratings:
    +17 / 0 / -0
    My Motion Simulator:
    2DOF
    Welcome, and welcome to your newest addiction, I just completed my first motion seat mover (2DOF) and the first time I used it I couldn't help a grin from ear to ear, that being said an hour later I was already starting to think of what else I could add.

    Regarding your decision about seat mover design. In addition to your storage requirement, you need to consider what type of motors you will be using also. If your going to be using smaller motors your going to want as much leverage as possible not only to produce snappy,strong movements, but also to keep temperatures down and prolong the life of your motors/psu/motor controllers.

    I used the PGsaw 50:1 80 rpm 12v 60Nm Torq. Motors from Ebay for a compact (under the seat mounted motor) and I can say the experience is amazing, but if you don't have as much torque i'd definitely consider going over the shoulder.
    • Agree Agree x 1
    • Useful Useful x 1
  3. CBC_North

    CBC_North Member

    Joined:
    Jun 29, 2018
    Messages:
    40
    Occupation:
    Computer Engineer
    Location:
    Ottawa, Canada
    Balance:
    333Coins
    Ratings:
    +34 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino
    @Zeraxx Thanks for the welcome, I've actually already ordered the identical motors (50:1 from pgsaw on ebay). I figured the extra torque will give me a little more flexibility in my design. The motors should be here tomorrow.

    I've paired those with two 750W Dell NPS-750BB power supplies. Got them used off ebay for $32 CAD + shipping from ebay.

    IMG_20180710_182022.jpg

    I also bought the universal joint for the platform. There's a very good junk yard near me where you pull your own parts and pay a flat fee per part type despite what car it came from. It's where I got the seat for the rig in the first post. $40 CAD for a passenger seat from a 2007 Mitsubishi eclipse. It's actually fairly nice with suede on the bolsters and headrest but its fairly heavy. I was originally going to pull a driveshaft from the yard to salvage a u-joint ($36) but took a trip to princess auto first and am glad I did. For only $4 more I was able to get a nice beefy hardened steel universal joint and not have to crawl under a car to saw it out.

    IMG_20180710_182221.jpg IMG_20180710_182303.jpg

    A co-worker has a mig welder I can loan and I have welded in the past but I might bring this to a proper shop to get a top and bottom flange/plate welded to it. Will depend on what kind of a quote they give me. I plan on making the base/motor mounts out of heavy aluminum square stock and plate. I have a good blade for cutting aluminum on my tablesaw so I would be able to make very accurate cuts. My CNC router is also nearing completion and I'm optimistic that I will be able to mill up to 1/4" aluminum plate with it (albeit slowly). It's a "Mostly Printed CNC" (MPCNC).
    IMG_20180710_183342.jpg

    Going to start the CAD for the base tonight.
    • Like Like x 1
  4. CBC_North

    CBC_North Member

    Joined:
    Jun 29, 2018
    Messages:
    40
    Occupation:
    Computer Engineer
    Location:
    Ottawa, Canada
    Balance:
    333Coins
    Ratings:
    +34 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino
    After combing through almost the entirety if the projects forum I've decided to go with a compact desk racer vs the shoulder mounted design for the following reasons:
    - Simpler and cheaper to fabricate. Won't have to fabricate the tall metal frame that extends up the back of the seat and my connector rods can be much shorter. This will limit welding as well.
    - Smaller footprint. Half of my unfinished basement (about 14' x 20') is my VR mancave. This is going in the corner of my VR play space so the larger it is, the more space I will lose from the area I use to play other games.
    - The motors I have (pgsaw 50:1) should be plenty strong for this type of rig.

    Any counter arguments to the above?

    As for a compact seat mover design, when mounting the connecting rods to the side of the seat, any advantages in mounting near the back vs the front? With a person in the seat I'm thinking the centre of gravity will likely be around the center of the chair base so neither way will give any more leverage than the other? If I mount it near the back I'm thinking I can drill a hole in the metal frame brackets of the reclining mechanism in the seat. If I mount near the front I will have to fabricate external brackets.
  5. Zeraxx

    Zeraxx Member

    Joined:
    Jun 28, 2018
    Messages:
    38
    Balance:
    188Coins
    Ratings:
    +17 / 0 / -0
    My Motion Simulator:
    2DOF
    Great choice, that's the same reasons and design choice I did for my setup. If you wanna see it in action check out this link.


    Regarding CG position, my arms connect to MDF plywood, and then the UJoint is mounted so the center is slightly is about 2/3 back from the front of the chair.

    I also have sliders for my chair which is nice for a "fudge" factor lol, your going to love it the PGSAW 50:1 have plenty of torque, mine don't even get luke warm after hours of use. Just make sure you have some beefy speed controllers.
    • Like Like x 2
  6. CBC_North

    CBC_North Member

    Joined:
    Jun 29, 2018
    Messages:
    40
    Occupation:
    Computer Engineer
    Location:
    Ottawa, Canada
    Balance:
    333Coins
    Ratings:
    +34 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino
  7. CBC_North

    CBC_North Member

    Joined:
    Jun 29, 2018
    Messages:
    40
    Occupation:
    Computer Engineer
    Location:
    Ottawa, Canada
    Balance:
    333Coins
    Ratings:
    +34 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino
    Sigh, used tab to autocomplete your name and ended up posting before I was finished...

    I'll be happy if I can achieve something similar. I'm planning on using a pair of monster moto boards, one to drive each motor.

    My CAD is progressing well. Using Fusion 360 to model everything so that I'm sure it fits together before I start fabricating. This will give me more accurate numbers to plug into the sim calc program as well. I've changed my plans a bit and now will have the following:
    • Base of the platform out of wood to save on costs. Also matches the rest of the frame which is currently wood.
    • Seat base will be made of 1 inch steel tubing with an MDF or plywood platform to which the u-joint will attach. I MAY try this with just the 3/4 plywood platform as the metal seat reals I'm bolting it to may be rigid enough.
    • Motor mounts will be made of 3/16" aluminum plate cut on the CNC (hopefully).
    • Potentiometer brackets will be designed in fusion 360 and 3d printed.
    I should have some CAD to show in a few days. In the meanwhile, some new packages showed up today. New wheel for my T150 base. The adapter is being 3d printed as I'm typing this:

    Racing_wheel.jpg Wheel_adapter.jpg

    Next up after that is to redesign and reprint the faces of my DIY pedals.
  8. CBC_North

    CBC_North Member

    Joined:
    Jun 29, 2018
    Messages:
    40
    Occupation:
    Computer Engineer
    Location:
    Ottawa, Canada
    Balance:
    333Coins
    Ratings:
    +34 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino
    Made progress on the new wheel. I have a thrustmaster T150 base which is great but I really don't like the size or the feeling of the rim. I'm also having a mechanical issue with one of my shift paddles.

    The plan is to use the following adapter to attach the new wheel to my existing base:
    https://www.thingiverse.com/thing:2762614

    Combine that with the magnetc paddle shifters from here:
    https://www.thingiverse.com/thing:1678086

    Finally, I modified the button plate from the above project and 3d printed it. Printed on paper to test the fit first:
    IMG_20180717_210202.jpg

    Sliced with a heavy infill and printed:
    button_plate_slicer.png IMG_20180717_234741.jpg

    Also printed the adapter:
    Wheel_adapter.jpg

    Fits well on the wheel with the adapter. Test fit of the buttons and knob also worked well (rest of the buttons are in the mail). The knobs will be on rotary encoders that will simulate up/down and left/right of the old dpad.
    IMG_20180718_090820.jpg IMG_20180718_135231.jpg IMG_20180718_135242.jpg

    The 3d printed button panel seems to be sturdy enough when bolted to the wheel. If I find it has any issues later on I'll consider cutting this out of a piece of aluminum plate.
    • Like Like x 2
  9. CBC_North

    CBC_North Member

    Joined:
    Jun 29, 2018
    Messages:
    40
    Occupation:
    Computer Engineer
    Location:
    Ottawa, Canada
    Balance:
    333Coins
    Ratings:
    +34 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino
    Almost 2 months since I last posted. Got busy with other things but also had a huge headache with the software for my steering wheel. I was working off existing code to have an arduino emulate the Thrustmaster T150 wheel but I could not get it to work with the wheel base. Worked perfectly on the bench, emulated the wheel perfectly but would not talk to the wheel base correctly. After weeks of messing around with it I don't have the proper gear to troubleshoot it any further (logic analyzer). So.... I've put in an order for some shift registers that are effectively identical to the contents of the original wheel and I'll recreate it with actual hardware. Something I should have done a while ago. This has been put aside for now until I get the parts.

    What I'm working on now is fabricating some brackets to hold the motor feedback potentiometers. I've drawn up some brackets in fusion 360 that will work with some 12mm -> 6.35mm aluminum flex couplers. I'm 3d printing a test model tonight to see how they fit. They're sized off the pgsaw motor models that were uploaded here so if they work I'll upload the STLs so others can print them as well.

    Potentiometer_adapter_model.png Potentiometer_adapter_slicer.png
    • Like Like x 1
  10. Kranky Pantz

    Kranky Pantz Active Member

    Joined:
    Sep 9, 2018
    Messages:
    354
    Location:
    Canada, Eh!
    Balance:
    1,247Coins
    Ratings:
    +290 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, JRK, Motion platform
    Hello fellow 'Nuck!!!!

    Damn, it looks like we're both building practically the same design of seat mover...cool!

    I have the same 50:1 motors as you as well, sourced from PGSaw, they were awesome to deal with directly (bypassing eBay) and also made me up a flanged U-Joint.

    That 3D printed potentiometer bracket paired with aluminum couplers looks slick!
    Did it work as planned???

    How are you for sourcing your threaded rods & rod ends in Canada?
    I'm having a heck of a time, but it looks like Acklands-Grainger may have what is needed, and I believe that they are nationwide.

    I'll be watching your thread as it progresses, Cheers! :cheers
  11. CBC_North

    CBC_North Member

    Joined:
    Jun 29, 2018
    Messages:
    40
    Occupation:
    Computer Engineer
    Location:
    Ottawa, Canada
    Balance:
    333Coins
    Ratings:
    +34 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino
    @Kranky Pantz I'm using the rod ends from aliexpress that are often recommended on here:
    https://www.aliexpress.com/item/4pc...ight-hand-tie-rod-end-bearing/1559309095.html
    I found some at Princess Auto as well but they were much more expensive and didn't have a closed design.
    As for threaded rod, I have a local place here that specializes in fasteners so I go there. However, I'm sure I've seen the identical threaded rod display in every home depot. You could also try Princess Auto.

    The potentiometer brackets came off the printer well but the model I was working off of for the motors (the one linked in the FAQ) is slightly off for the following:
    -Distance between the two bottom mounting holes and top mounting hole
    -Postion of the shaft between the mouting holes.

    It's not off by much but its enough that I'll need to modify the design and reprint it. There was enough flex to get it mounted to the motor but as you can see the motor shaft doesn't line up with the coupler. It's just as well anyways because I need to tweek the design to add a little strength where the arms meet the platform that houses the potentiometer.
    IMG_20180922_101817.jpg IMG_20180922_095231.jpg IMG_20180922_102129.jpg IMG_20180922_102113.jpg
    • Like Like x 2
  12. CBC_North

    CBC_North Member

    Joined:
    Jun 29, 2018
    Messages:
    40
    Occupation:
    Computer Engineer
    Location:
    Ottawa, Canada
    Balance:
    333Coins
    Ratings:
    +34 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino
    Second print of the potentiometer adapter has the right space for the mounting holes but still slightly misaligned with the shaft. Looks like third time will be the charm. I'll post pictures as well as the CAD and STL files when I reprint and confirm the fit.

    On another note, the custom steering wheel for my T150 is finally working. I stopped trying to emulate the original wheel with an arduino and just used shift registers to remake the internals correctly (the way it is on the original). I scrapped the idea of just a plate as it was fairly flimsy. The new design is an enclosure that covers all the electronics and adds rigidity to the button plate. It's paired with a set of magnetic paddle shifters that I found on thingiverse and modified slightly for the limit switches I had. It's all printed in PLA+ on an Ender 3.
    IMG_20180805_090427_1.jpg IMG_20180805_091206.jpg IMG_20180805_182318.jpg IMG_20180928_130043.jpg IMG_20180928_131714.jpg IMG_20180928_142229.jpg
    • Like Like x 3
  13. CBC_North

    CBC_North Member

    Joined:
    Jun 29, 2018
    Messages:
    40
    Occupation:
    Computer Engineer
    Location:
    Ottawa, Canada
    Balance:
    333Coins
    Ratings:
    +34 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino
    Potentiometer bracket design is now finished. As shown in the picture the mounting holes and shaft now line up perfectly. I'm not happy with the quality of the print itself as I was messing with some settings so I will reprint these once I nail down my settings.

    IMG_20181001_162214.jpg

    If anyone would like to use these, below are links to the raw fusion 360 file if you need to make changes as well as an STL file if you simply want to print them.

    Note: If you are going to print these I always design any through holes that will accept a bolt ever so slightly smaller than required. After they print I then run a drill bit through the hole to make it the exact size. For this model the mounting holes should use a 1/4" bit and the pot mount is 3/8".

    Fusion 360 link: https://a360.co/2QqdVOi

    Attached Files:

    • Like Like x 3
    • Useful Useful x 2
    Last edited: Oct 3, 2018
  14. noorbeast

    noorbeast VR Tassie Devil Staff Member Moderator Race Director

    Joined:
    Jul 13, 2014
    Messages:
    20,460
    Occupation:
    Innovative tech specialist for NGOs
    Location:
    St Helens, Tasmania, Australia
    Balance:
    144,596Coins
    Ratings:
    +10,741 / 52 / -2
    My Motion Simulator:
    3DOF, DC motor, JRK
    Added to the 3D Printed FAQs: https://www.xsimulator.net/community/faq/3d-printing.129/
  15. Deane

    Deane Old Fart

    Joined:
    Aug 25, 2018
    Messages:
    212
    Occupation:
    Retired
    Location:
    Wirrina Cove, South Australia
    Balance:
    793Coins
    Ratings:
    +89 / 3 / -0
    My Motion Simulator:
    2DOF
    I'm not being critical but I have built a few CNC routers, four including one CNC plasma cutter and to be able to accurately cut ally you need a rigid machine and the more rigid the better
    as you will end up missing steps and losing accuracy with any flex in your table or gantry.
    Just limit your cut depth and travel speeds to minimize flex.
    You will understand better once you use your CNC
    The two pics show some mounts that I cut from 16mm. ally plate with my first CNC Router pictured which was a welded steel base and all ally 12mm. plate gantry.
    It did cut them , slowly but that still had flex issues that limited what I could cut accurately. ally cut.JPG frontside.JPG ozito mount.JPG
    • Like Like x 1
  16. CBC_North

    CBC_North Member

    Joined:
    Jun 29, 2018
    Messages:
    40
    Occupation:
    Computer Engineer
    Location:
    Ottawa, Canada
    Balance:
    333Coins
    Ratings:
    +34 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino
    @Deane I think it really just comes down to expectations. I'm not expecting it to be able to do anything too crazy. I have a good idea of what it should be able to do as it's a super popular design and there's tons of examples of it working.
    https://www.v1engineering.com/aluminum-guide/
    A lot of it comes down to a really shallow depth of cut which is fine with me as I won't be cutting aluminum on it often. There's also a lot you can do in the CAM stage to help out with the limitations of the machine. If I can get anything close to the video that is in the link I posted I'll be happy.

    On a side note, I've eliminated those aluminum mounts from my simulator design so I won't have to use the CNC for this anyways.
  17. Deane

    Deane Old Fart

    Joined:
    Aug 25, 2018
    Messages:
    212
    Occupation:
    Retired
    Location:
    Wirrina Cove, South Australia
    Balance:
    793Coins
    Ratings:
    +89 / 3 / -0
    My Motion Simulator:
    2DOF
    To quote a comment on that site " More rigidity is king!! "
    And Backlash is your enemy so linear rails with anti-lash ballscrews are money well spent and will speed up how fast you can push your stepper motors.
    Ally cuts very well with a carbide tip circular saw and metho for lube. You can also use a hand held router as well for chamfering edges for example.
  18. CBC_North

    CBC_North Member

    Joined:
    Jun 29, 2018
    Messages:
    40
    Occupation:
    Computer Engineer
    Location:
    Ottawa, Canada
    Balance:
    333Coins
    Ratings:
    +34 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino
    Lots of progress but haven't updated much lately, gonna be a big post... Started converting the front of the old rig to work with the new seat mover assembly. The plan is to have them as two separate pieces initially and only connect them if necessary. They're both pretty heavy so I don't think it'll be much of an issue. If I have problems during testing, the base of the front and the back will be identical width so it will be easy to attach them.

    First order of business was to cut the old rig in half with a handsaw. I cut it directly under the steering wheel.

    DSCN4579.JPG

    The main electrical supply for the seat mover base will plug into the house from the front half. It's wired to an emergency stop switch meant for woodworking equipment (35A @ 120V) before snaking its way under the front half where I wired a standard two plug wall outlet. The idea is to run two server power supply cables from the front half to the seat mover base and the emergency switch will kill all power to everything in the seat mover. Also under the front half is the power supply and 2 channel amplifier for the bass shakers but I'll get into that another time.

    DSCN4583.JPG DSCN4584.JPG DSCN4591.JPG

    The new wheel and button plate is mounted on the Thrustmaster T150 base and is fully working. I'm also testing out a new position for the H-Shifter and handbrake. I like the shifter mounted here but the handbrake is a little awkward and feels like it's too far away to comfortably operate. I might move it to the inside of the shifter if there's enough clearance above my legs. Both of these run to the same control box mounted on the side of the front assembly. It houses the amplifier for the load cell in the handbrake as well as the arduino that emulates a joystick for both the shifter and handbrake.

    DSCN4588.JPG DSCN4589.JPG DSCN4594.JPG DSCN4596.JPG

    The pedals are remaining basically the same. I do find the brake's a little stiff and I think I'll swap it out for a softer spring or a urethane spring if I can find one for a reasonable price. All the pedals run off of load cells and again are an emulated joystick using an arduino. An electronics box is going to be 3d printed to cover the boards.

    DSCN4586.JPG DSCN4597.JPG DSCN4603.JPG

    The seat mover base is also getting to the point where it can be tested for the first time. The main wooden structure is made using 2x4 (The good s4s stuff, not the construction grade stuff). Joints were made using pocket holes.

    IMG_20180929_174229.jpg IMG_20180930_155018.jpg

    The motor will mount to the base using a combination of the wooden frame and some beefy aluminum angle stock. The 2x4 was shaped to conform to the curve on the inside of the angle stock using a hand plane and it is attached using 1/4" lag screws. Motors are good and sturdy when mounted.

    IMG_20180929_132307.jpg IMG_20180929_133318.jpg IMG_20180929_134713.jpg IMG_20180929_142058.jpg IMG_20180929_143008.jpg IMG_20180929_143056.jpg IMG_20180929_144101.jpg IMG_20180930_162157.jpg IMG_20180930_162311.jpg IMG_20180930_162328.jpg

    The bottom of the frame was closed in using 3/4" MDF for rigidity. Additional cross braces make it even stronger and act as a raised platform for the seat's universal joint. It was then taken outside for paint.

    DSCN4563.JPG DSCN4562.JPG

    The black spray paint definitely improves the look. The open section on the front of the base is where the Moto monster's are going to live. I cut a top cover out of 1/4" mdf to protect the electronics as well as to mount the 120 mm fans that will cool the motor drivers. I think I'm going to wrap this in carbon fiber vinyl instead of painting it black. I have a bunch of vinyl left over from a car project I did years ago.

    DSCN4564.JPG DSCN4565.JPG DSCN4566.JPG DSCN4569.JPG

    Holes were cut in the front of the frame to house the inlets for the server power cords which will run from the front of the simulator to the seat mover base. These run internally to the two 750W server power supplies housed under the cross supports for the chair joint. The power supplies are secured in place using some extra framing brackets I had lying around. Some shelf liner was hot glued to one face and then the other side was screwed into the bottom of the base. They are held in place quite snugly.

    DSCN4616.JPG DSCN4570.JPG DSCN4610.JPG DSCN4611.JPG DSCN4613.JPG

    Finally, today I was working on a cross support that will span between the top mounting hole on each motor. Similar to the one from @noorbeast 's simulator. Should give them more rigidity. The support was to be made using a piece of 1/2" aluminum round stock, drilled and threaded on each end so that the bolt going through the top hole of each motor will simply screw into each end. The support is too long to fit in my benchtop drill press so I cut and drilled a small section on the press and clamped this to the top of the longer section in my bench vise. I then used the hole in the short section as a guide for my hand drill. Everything worked well until I was finishing tapping the last ~2 mm of the second hole. Slightly too much force and Bam!, snapped off the tap. About 1 inch of it is still in the hole.... That's about when I called it a day and grabbed some tacos and beers.

    DSCN4571.JPG DSCN4572.JPG DSCN4574.JPG DSCN4576.JPG DSCN4577.JPG

    Attached Files:

    • Like Like x 3
  19. CBC_North

    CBC_North Member

    Joined:
    Jun 29, 2018
    Messages:
    40
    Occupation:
    Computer Engineer
    Location:
    Ottawa, Canada
    Balance:
    333Coins
    Ratings:
    +34 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino
    Another long gap since the last update but good news to report. Simulator is finally moving! Currently driving it using an arduino nano flashed with SMC3 and two monstermoto's (one for each motor). One of the monstermoto drivers was dead right out of the box. Wouldn't output in one direction. Going to drive these until they're dead and then decide what to do after that, buy more monster moto's or switch to a sabertooth... Problem with the monstermoto's is that ordering from china now will take at least a few months due to the recent strike by Canada post and the massive backlog of international parcels they have to get through.

    https://photos.app.goo.gl/Nhbj5Wybv4kbA4tP8

    Video is just testing one motor at a time using SMC3 utility (Sorry for potato quality, better video will be uploaded once it's fully tuned). Nice and slow for now at about 20% of max PWM. Going to work through the tuning now and get it running with simtools instead of just the test utility.

    Still need to finish:
    -Additional motor crossbar to brace them (There was some flex during testing)
    -Base shaker amp mounting and wiring (shakers are mounted in/under the seat already)
    -Finalize harness mounts
    -Redesign front half a bit since the seat is slightly higher than expected so there's not enough clearance under the wheel deck.
    -Finish button box.
    -Re-tune springs in break pedal (current one is too stiff)
    -Finalize mounting of shifter and handbrake

    That's still a long list, but I've got vacation coming up soon so I'll have more time to work on it.
    • Like Like x 1
  20. CBC_North

    CBC_North Member

    Joined:
    Jun 29, 2018
    Messages:
    40
    Occupation:
    Computer Engineer
    Location:
    Ottawa, Canada
    Balance:
    333Coins
    Ratings:
    +34 / 0 / -0
    My Motion Simulator:
    2DOF, DC motor, Arduino
    Trying to perform the PID tuning tonight using SMC3 setup utility, I'm finding some weird behavior. Sometimes the motors get "stuck" in one position. More details:
    • I'm running the monstermotos as a half-bridge (one board per motor) as per the instructions in the SMC3 thread.
    • When it works, it works flawlessly (95% of the time)
    • The potentiometer feedback is spot on. Any time the motor moves the feedback graph (green) moves.
    • When it stops responding it's usually when I'm just switching to that motor and the target postion is a ways away from the feedback position or I've left the motor in one position for a while and manually step the target position a fair ways away from the feedback.
    • The utility indicates it's outputting the max PWM and I've confirmed this at the arduino PWM pin as well as the monstermoto contacts using a multimeter.
    • The direction output from the arduino seems to be correct (one direction is +5v and the other is zero. These pins swap if I jump the target location over the feedback location but don't go near it)
    • The output voltage from the monstermoto at this time is zero.
    • The heatsink on the driver does not get warm to the touch at this time.
    • To get out of this "stuck" position, if I go to the utility and pull the target postion to the feedback position then away it will eventually start working again.
    • Can see this in the posted graph where I pull the target position (blue) towards then away from the actual position (green) multiple times. The first two times don't fix the problem but the third time does and the motor begins following the target position again. It will work again until I leave the motor idle for a while.
    • This is happening with both of my motors.
    Is this a quirk with manual mode in the utility? Maybe with the monstermoto boards? Any help would be appreciated.
    smc3_issues.png