Shop OBEX P1 Docs P2 Docs Learn Events
Astronomy Ideas — Parallax Forums

Astronomy Ideas

ArchiverArchiver Posts: 46,084
edited 2001-04-05 20:14 in General Discussion
I am currently building a 13.1 newtonian reflector. I decided I want
to put a drive system on it and I was thinking maybe the stamp BS2IC.
Problems have risen that i am trying to figure out and I was hoping
to get input from you nice people.

The main problem I have is trying to locate right acension and
declination. The earth turns one a day, the earth goes around the sun
in 364.256 days. can the stamp do math like this? I need this to
calculate the positions of the stars so that the stamp will know
where to put the telescope given any coordinate point. basically I
have to create a moving time based map that is moving, and the stamp
needs to know where these points are on the map and move a telescope
to each and every point when requested.
Any suggestions would be sicerely appreciated. Robert Jones

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2001-03-27 01:24
    I have built several scopes before including a 17" heliostat, and I
    have modest but rich experience witht he stamp.

    The problem with BS2 is that it doesn't have floating point
    processing. This makes dealing with decimals and negatinve numbers,
    which is very important in astronomical calculation next to impossible
    to achieve the accuracy required. The second problem with stamp is
    the memory. With the Stamp's limited EEROM, you will not be able to
    store a sufficient data base for even Mag 1 stars!

    Here is what I suggest;

    Get a laptop and do all your ephemiral calculation on it. You may
    even be able to use one of the off the shelf programs such as Sky IV
    to do that for you. Get the laptop to talk to the BS2 via RS232 via
    VB 5 or other programs, which is reliable and fast. Then the stamp
    will control the position of the DEC motor, and activate a slewing
    motor to lock on a certain RA-Dec position, and then trun a clock
    motore for tracking.

    The stamp is great for interfacing to hardware such as motors, relays,
    lights etc. But it is not a computer.

    e-mail me at alnajjar@s... if you have other questions.


    Al



    --- In basicstamps@y..., R_JONES22@y... wrote:
    > I am currently building a 13.1 newtonian reflector. I decided I want
    > to put a drive system on it and I was thinking maybe the stamp
    BS2IC.
    > Problems have risen that i am trying to figure out and I was hoping
    > to get input from you nice people.
    >
    > The main problem I have is trying to locate right acension and
    > declination. The earth turns one a day, the earth goes around the
    sun
    > in 364.256 days. can the stamp do math like this? I need this to
    > calculate the positions of the stars so that the stamp will know
    > where to put the telescope given any coordinate point. basically I
    > have to create a moving time based map that is moving, and the stamp
    > needs to know where these points are on the map and move a telescope
    > to each and every point when requested.
    > Any suggestions would be sicerely appreciated. Robert Jones
  • ArchiverArchiver Posts: 46,084
    edited 2001-03-27 05:51
    Check out this web site

    http://zebu.uoregon.edu/~mbartels/altaz/altaz.html

    to computerize your scope.

    Richard
  • ArchiverArchiver Posts: 46,084
    edited 2001-03-29 16:21
    Robert:

    I too, am working on a telescope drive using the Basic Stamp 2. I thought that
    I would start with a simple single axis drive controller. I have decided to use
    a National Semiconductor LM629 Precision Motion Controller to generate the DC
    PWM. I made the decision to use the LM629 using my experience with the Basic
    Stamp generated PWM and Motor Mind B module. Neither could provide the features
    and accuracy I sought. The work with the LM629 is still in the beginning
    stages. My problems are with the programming of the LM629. I have searched for
    help with the LM629 and Basic Stamp on this BBS without success. I hope you can
    share your ideas with me.

    If I get the drive working, I plan to move on to the star chart. The LM629 has
    a "home" command where the device recognizes a zero point. Using the home
    command and a table look-up, I think the combination of the LM629 and Basic
    Stamp will meet your requirements. The relative positions of deep sky objects
    from "home" remain constants, therefore, recalculation is unnecessary.

    Please keep me informed of your progress.

    Best regards,
    Graham
  • ArchiverArchiver Posts: 46,084
    edited 2001-04-05 19:46
    Use a PocketPC to control the stamp, which in turn would control the
    telescope. Write a program for the PPC that "Hooks" to the AZ. and
    ALT. output from Pocket Universe 2000 at
    http://stellarm.hostme.com/Software/pu2000.htm
  • ArchiverArchiver Posts: 46,084
    edited 2001-04-05 19:54
    RE: [noparse][[/noparse]basicstamps] Re: Astronomy Ideas

    I'd like to use my PPC to get a dump from my BS2 circuit. I need the cable that goes from PPC to the BS2 circuit. Where would one get such cables. I will also need to tweak the BS2 end of the cable to make this work I presume.


    Please advise

    thanks
    nagi


    Original Message

    From: tunatunup2000@yahoo.com [noparse]/noparse][url=mailto:tunatunup2000@yahoo.com]mailto:tunatunup2000@yahoo.com[/url
    Sent: Thursday, April 05, 2001 1:46 PM
    To: basicstamps@yahoogroups.com
    Subject: [noparse][[/noparse]basicstamps] Re: Astronomy Ideas




    Use a PocketPC to control the stamp, which in turn would control the
    telescope. Write a program for the PPC that "Hooks" to the AZ. and
    ALT. output from Pocket Universe 2000 at
    http://stellarm.hostme.com/Software/pu2000.htm


    ·

    Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
  • ArchiverArchiver Posts: 46,084
    edited 2001-04-05 20:12
    You just connect the output pin from the PPC to the input pin of the
    Stamp and vice versa, the input pin from the PPC is connected to the
    output pin of the stamp. You cannot simply use a 9-pin male to male
    connector for this. You need to build a special "Cross over" type
    connector from the BS2 cable to the PPC cable. Don't forget to ground
    the two together and connecting a 470k resister on the ground line
    maybe a good idea but I just learned electronics in January and may
    be wrong about that.
  • ArchiverArchiver Posts: 46,084
    edited 2001-04-05 20:14
    RE: [noparse][[/noparse]basicstamps] Re: Astronomy Ideas

    Would you know of a place where I can buy a cable for this app?

    thanks

    nagi


    Original Message

    From: tunatunup2000@yahoo.com [noparse]/noparse][url=mailto:tunatunup2000@yahoo.com]mailto:tunatunup2000@yahoo.com[/url
    Sent: Thursday, April 05, 2001 2:13 PM
    To: basicstamps@yahoogroups.com
    Subject: [noparse][[/noparse]basicstamps] Re: Astronomy Ideas



    You just connect the output pin from the PPC to the input pin of the
    Stamp and vice versa, the input pin from the PPC is connected to the
    output pin of the stamp. You cannot simply use a 9-pin male to male
    connector for this. You need to build a special "Cross over" type
    connector from the BS2 cable to the PPC cable. Don't forget to ground
    the two together and connecting a 470k resister on the ground line
    maybe a good idea but I just learned electronics in January and may
    be wrong about that.


    ·

    Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
Sign In or Register to comment.