Shop OBEX P1 Docs P2 Docs Learn Events
wheel chair project — Parallax Forums

wheel chair project

ArchiverArchiver Posts: 46,084
edited 2004-05-24 16:34 in General Discussion
I'm building a wheel chair for a friend using two brushed motors that
are controlled by power modules opto-coupled to a BS2SX.
I can run the chair while sitting in it with my lap top using pulsout
and pause but want to change over to joystick control.
Is there a resource anyone knows about on how to use a joystick
(actually two pots)as an input device to control a chair?
The H-bridge forward/reverse is not the challenge, using an analog
input is what has me stumped.
thanks
chris

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2004-04-27 10:58
    At 01:49 AM 4/27/04 +0000, n8101g wrote:
    >I'm building a wheel chair for a friend using two brushed motors that
    >are controlled by power modules opto-coupled to a BS2SX.
    >I can run the chair while sitting in it with my lap top using pulsout
    >and pause but want to change over to joystick control.
    >Is there a resource anyone knows about on how to use a joystick
    >(actually two pots)as an input device to control a chair?
    >The H-bridge forward/reverse is not the challenge, using an analog
    >input is what has me stumped.
    >thanks
    >chris

    Chris -

    Take a look here for wheelchair motor controllers, joystick interfaces, and
    other similar equipment: http://divelec.tripod.com/id1.html . This all designed
    for actual use on wheelchairs which a good deal of similar equipment is not.

    Regards,

    Bruce Bates
  • ArchiverArchiver Posts: 46,084
    edited 2004-04-27 14:15
    --- In basicstamps@yahoogroups.com, "n8101g" <n8101g@y...> wrote:
    > I'm building a wheel chair for a friend using two brushed motors
    that
    > are controlled by power modules opto-coupled to a BS2SX.
    > I can run the chair while sitting in it with my lap top using
    pulsout
    > and pause but want to change over to joystick control.
    > Is there a resource anyone knows about on how to use a joystick
    > (actually two pots)as an input device to control a chair?
    > The H-bridge forward/reverse is not the challenge, using an analog
    > input is what has me stumped.
    > thanks
    > chris


    Hi Chris,

    The options for analogue input are pretty wide.

    Read up on POT and RCTime as inputs to see if you can get the
    resolution you need.

    I am thinking you can get enough as for my experiances, you can live
    with a handfull of 'steps' in the speed ranges.

    If you can divide a pot input to 10 steps, then the wheel chair would
    appear to shift gears as you moved up in steps. But, I'm betting you
    can do much better than that.

    Also,instead of a linear 1:1 output speed to input signal, I'd
    recomend you try a much lower first gear. My experiance is more with
    hi-lift jacks on construction sites, but the idea is the same.

    the problem for is that I am not on them often enough and when I'm 20
    feet in the air and want to nudge the thin forward a few inches, it
    jumps and scares the be-geebers out of me.

    I would much preferr a non-linear ramping with a very slow crawl to
    start. And IMHO, the difference between 3/4 and full speed is not as
    important.

    And, if you want really high resolution, use out ChipCircuit-ADC. It
    sandwiches between the Stamp and the stamp socket so add 10 channels
    of 12 bit ADC. And the code snips are there so you can plug it in
    and get it running quickly.

    It may be overkill for your app, but it is worth a look.

    http://www.visualmuses.com/chipcircuit/index.html

    Dave
  • ArchiverArchiver Posts: 46,084
    edited 2004-05-19 01:37
    If you don't 45 degree travel direction, how about using the the joystick to operate forward ,back, left, right switches.

    Bruce Bates <bvbates@u...> wrote:At 01:49 AM 4/27/04 +0000, n8101g wrote:
    >I'm building a wheel chair for a friend using two brushed motors that
    >are controlled by power modules opto-coupled to a BS2SX.
    >I can run the chair while sitting in it with my lap top using pulsout
    >and pause but want to change over to joystick control.
    >Is there a resource anyone knows about on how to use a joystick
    >(actually two pots)as an input device to control a chair?
    >The H-bridge forward/reverse is not the challenge, using an analog
    >input is what has me stumped.
    >thanks
    >chris

    Chris -

    Take a look here for wheelchair motor controllers, joystick interfaces, and
    other similar equipment: http://divelec.tripod.com/id1.html . This all designed
    for actual use on wheelchairs which a good deal of similar equipment is not.

    Regards,

    Bruce Bates



    To UNSUBSCRIBE, just send mail to:
    basicstamps-unsubscribe@yahoogroups.com
    from the same email address that you subscribed. Text in the Subject and Body of the message will be ignored.

    Yahoo! Groups Links







    Do you Yahoo!?
    SBC Yahoo! - Internet access at a great low price.

    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2004-05-19 15:32
    You may wish to use a high quality joystick as well. You can get arcade
    machine quality joysticks with real microswitches for input from.
    http://hapcontrols.com They are relatively inexpensive as well.
    $8.95 for the 4 position standard joystick. it operates in 8 positions
    diagonally by accessing two switchs at once. I have used them for years and
    never had a failure. Hap also sells high quality pushbutton switchs for a
    few dollars.
    Good luck.
    -Kerry


    At 05:37 PM 5/18/04 -0700, you wrote:
    >If you don't 45 degree travel direction, how about using the the joystick
    to operate forward ,back, left, right switches.
    >
    >Bruce Bates <bvbates@u...> wrote:At 01:49 AM 4/27/04 +0000,
    n8101g wrote:
    >>I'm building a wheel chair for a friend using two brushed motors that
    >>are controlled by power modules opto-coupled to a BS2SX.
    >>I can run the chair while sitting in it with my lap top using pulsout
    >>and pause but want to change over to joystick control.
    >>Is there a resource anyone knows about on how to use a joystick
    >>(actually two pots)as an input device to control a chair?
    >>The H-bridge forward/reverse is not the challenge, using an analog
    >>input is what has me stumped.
    >>thanks
    >>chris
    >
    >Chris -
    >
    >Take a look here for wheelchair motor controllers, joystick interfaces, and
    >other similar equipment: http://divelec.tripod.com/id1.html . This all
    designed
    >for actual use on wheelchairs which a good deal of similar equipment is not.
    >
    >Regards,
    >
    >Bruce Bates
    >
    >
    >
    >To UNSUBSCRIBE, just send mail to:
    >basicstamps-unsubscribe@yahoogroups.com
    >from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    >Yahoo! Groups Links
    >
    >
    >
    >
    >
    >
    >
    >
    >Do you Yahoo!?
    >SBC Yahoo! - Internet access at a great low price.
    >
    >[noparse][[/noparse]Non-text portions of this message have been removed]
    >
    >
    >
    >To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    >from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    >Yahoo! Groups Links
    >
    >
    >
    >
    >
    >
    Very respectfully, your obedient servant.
    Brig. Gen. Johnston Pettigrew

    Admin@M...
    WWW server hosting [url=Http://mntnweb.com]Http://mntnweb.com[/url]
    Kerry Barlow
    p.o. box 21
    kirkwood ny
    13795
    607-775-1575
  • ArchiverArchiver Posts: 46,084
    edited 2004-05-24 16:34
    Use the joystick to provide an analog Voltage to a comparitor. The other
    input of the comparitor has a pulse train on it. As the joystick moves, it
    changes the reference level, and the pulse train will have different widths
    depending upon where it's at. Different widths translate into different
    average power/Voltage levels to the motors.

    Original Message
    From: Philip Gmblin [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=v9iwKz2BJRjs0a0Jp2brNdo_wa0wNOnZjXPp-BWHj9hXDATQfeqG8TDU0t4zHdrkjTWLH3uU8lLCfFQO]pipeguy3153@y...[/url
    Sent: Tuesday, May 18, 2004 8:37 PM
    To: basicstamps@yahoogroups.com
    Subject: Re: [noparse][[/noparse]basicstamps] wheel chair project


    If you don't 45 degree travel direction, how about using the the joystick to
    operate forward ,back, left, right switches.

    Bruce Bates <bvbates@u...> wrote:At 01:49 AM 4/27/04 +0000, n8101g
    wrote:
    >I'm building a wheel chair for a friend using two brushed motors that
    >are controlled by power modules opto-coupled to a BS2SX.
    >I can run the chair while sitting in it with my lap top using pulsout
    >and pause but want to change over to joystick control.
    >Is there a resource anyone knows about on how to use a joystick
    >(actually two pots)as an input device to control a chair?
    >The H-bridge forward/reverse is not the challenge, using an analog
    >input is what has me stumped.
    >thanks
    >chris

    Chris -

    Take a look here for wheelchair motor controllers, joystick interfaces, and
    other similar equipment: http://divelec.tripod.com/id1.html . This all
    designed
    for actual use on wheelchairs which a good deal of similar equipment is not.

    Regards,

    Bruce Bates



    To UNSUBSCRIBE, just send mail to: basicstamps-unsubscribe@yahoogroups.com
    from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.

    Yahoo! Groups Links







    Do you Yahoo!?
    SBC Yahoo! - Internet access at a great low price.

    [noparse][[/noparse]Non-text portions of this message have been removed]



    To UNSUBSCRIBE, just send mail to:
    basicstamps-unsubscribe@yahoogroups.com
    from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.

    Yahoo! Groups Links
Sign In or Register to comment.