[roc-chat] Re: ROC Launch Control System

  • From: Mike & Nancy Kramer <kramer@xxxxxxxxxxxx>
  • To: roc-chat@xxxxxxxxxxxxx
  • Date: Tue, 09 Oct 2012 21:56:14 -0700

Gregg Halligan and I were discussing cables on the way home from Trailer cleaning and had an Idea to help nurse the current cables a bit.


Since each cable is a pass through to the next set of pads (center front passes to center mid passes to center far) the cables fro mid to far are only using 1/3 of the wires in the bundle. Could we get three cables using the same ends but only 1/3 the conductors to be used only from mid to far. This opens up a set of 'full cables' as spares (or rotate them in to replace some of the more worn cables. The smaller / 1/3 of the conductor cables will certainly cost less than the full cable.

I appreciate the thought that went into the original design where all the cables are universal but since we tend to always use the same cable for the same connection every time this may be an option. If we use the same end connectors this change should be pretty seamless.

Just a thought,

Mike Kramer


On 10/9/2012 10:52 AM, Ron McGough wrote:
Richard,
One big question,
Has there ever been a rocket accidentally launched due to a failure of the ROC Launch System? Answer: NO! All accidental launches have been caused by lack of knowledge of the RSO and or the Owner of the rocket. To my knowledge there has never been a "misfire" of the ROC Launch System since it was built in 2001. As for the layout of the launch system being rows of 6 spaced apart. This concept was arrived at after much thought and planning by a group of BOD members. Originally it was supposed to be 6 pads all with a minimum of 10 ft. between them, original launch leads were cut at lengths of 30', 20', 10', 10', 20', 30',in that order, these lengths enabled the 2 pads at the center to be at least 10 feet apart and then the rest of the pads were supposed to be set up at 10 ft. intervals. These lengths have changed as the years have passed due to shorter leads and the people doing the set up not knowing the proper layout. Why do we need coils of excess wire laying on the ground behind the pads when if the pads were laid out properly the wires would be the correct length? The ROC launch system was built with Safety and the ability to supply 30amps of power maximum to each launch pad. It was built with the idea that it would last for many years with almost trouble free operation (which it has). The control cables have lasted as planned and would still be in good shape had they had the proper treatment and not been driven over by ATV's and Vehicles. But alas some people just can't seem to figure out that you shouldn't try to shove a square peg in a round hole and that is why the cable connectors are in the shape they are. As for the LCO control boxes we never had any trouble with them until the system was left out in the rain a couple of years ago. The funny part about all this is that TCC's new launch system (24 pads) is built on the same concept for it's ability to safe and arm 30amps of power to each pad. They also use a larger 33amp hour sealed lead acid battery so that they are able to launch multiple large scale rockets using high amp igniters simultaneously for the whole weekend without fear of the battery going dead.
Enough for now,
Ron McGough

    ----- Original Message -----
    *From:* Richard Dierking <mailto:richard.dierking@xxxxxxxxx>
    *To:* roc-chat@xxxxxxxxxxxxx <mailto:roc-chat@xxxxxxxxxxxxx>
    *Sent:* Tuesday, October 09, 2012 9:33 AM
    *Subject:* [roc-chat] Re: ROC Launch Control System

    Good point.  There could be a high tone for armed and continuity,
    and low tone for armed with no continuity.
    I still think wireless to individual pads rather than groups of
    pads would be better.  For example, instead of left middle, center
    middle, and right middle, you would just have the middle row with
    lots of distance between the pads.  This makes it safer for people
    loading rockets.  Have you ever been loading your rocket next to
    someone you've never seen before prepping their complex rocket,
    and thought "I sure hope they know what their doing?"  Or,
    had someones rocket CATO 6 feet from your rocket as it sits on the
    pad?  Distance between pads is a good thing!
    I don't want a misunderstanding about what's on the table, because
    I see comments about the safety of a wireless system. If the
    individual pad has shunt and power switches, how could the rocket
    accidentally launch when being loaded?  If the launch control box
    gives a audible and visual warning that the pad is in an armed
    condition, the person would have to be ignoring the warning as
    they were loading their rocket and switch the power on during this
    warning.  If they're that stupid, they should be involved in
    another hobby like ham radio.
    Sorry, JK. Just wanted to see if any one's reading this stuff.
    Richard Dierking
    On Tue, Oct 9, 2012 at 8:20 AM, Jim - TFJ <jim@xxxxxxxxxxxxxxx
    <mailto:jim@xxxxxxxxxxxxxxx>> wrote:

        If you’re using a processor at each group of pads, you could
        program the buzzer/siren make a different sound if continuity
        is lost.

        Jim G.

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

        *From:*roc-chat-bounce@xxxxxxxxxxxxx
        <mailto:roc-chat-bounce@xxxxxxxxxxxxx>
        [mailto:roc-chat-bounce@xxxxxxxxxxxxx
        <mailto:roc-chat-bounce@xxxxxxxxxxxxx>] *On Behalf Of *Richard
        Dierking
        *Sent:* Monday, October 08, 2012 9:26 AM
        *To:* roc-chat@xxxxxxxxxxxxx <mailto:roc-chat@xxxxxxxxxxxxx>
        *Subject:* [roc-chat] Re: ROC Launch Control System

        The most important safety feature is having the shunt/power
        switch (mechanical switch) at the pad with a visual and
        audible warning that the pad is armed.  This puts the
        responsibility for safety back in the hands of the person
        loading their rocket.

        I think having a continuity check at the pad is a good thing,
        but don't think the continuity check at the LCO for a
        high-power rocket pad is that important.  If the rocket
        doesn't go when the button is pushed and there's continuity at
        the pad, it's a recycle and the igniter must be checked.  If
        the rocket doesn't go and there isn't continuity, the igniter
        must be checked. So, really what's the value of having a
        continuity check if the rocket doesn't launch?

        Regarding the battery, it shouldn't take a large battery for
        the individual launch pad controllers.  We launch 6 rockets
        all day using a 12 volt gel cell 7 Ah battery.

        Regarding the front row and model rocket pads, these could
        still use cables.  However, I think that some kind of digital
        system using Cat 5 cable would be better.  It's not expensive
        cable to replace if necessary, and a lot easier to deploy and
        hook up.

        If ROC budgeted to save $2000 per year (approx $175 per
        launch), this would probably be enough money to develop
        a wireless system and go wireless for the high-power pads in
        approximately 3 years.

        Richard

        On Mon, Oct 8, 2012 at 7:29 AM, Richard
        <rocket_hall@xxxxxxxxxxxxx <mailto:rocket_hall@xxxxxxxxxxxxx>>
        wrote:

        David is this possibly a XBEE module? The XBEE modules could
        accomplish  exactly what Richard's dream system would need. I
        have some experience with these too. Richard Dierking I can
        put together a couple of concepts both "dream system" and
        "partial dream system" The biggest problem I see would be
        batteries(one per pad). I won't be at ROCtober but will be at
        ROCstock.

        Richard C. Hall
        TRA 11515

        -----Original Message-----
        From: David Erbas-White
        Sent: Oct 7, 2012 7:14 PM
        To: roc-chat@xxxxxxxxxxxxx <mailto:roc-chat@xxxxxxxxxxxxx>
        Subject: [roc-chat] Re: ROC Launch Control System

        On 10/7/2012 6:03 PM, Richard Dierking wrote:

        In my 'real life' job I'm working with some wireless systems
        (actually, using a wireless module with our own proprietary
        control circuitry -- but as the module is FCC approved, don't
        need to worry about that end of it).  I have tested this
        system on the lakebed to over a mile, reliably.  If we were to
        come up with some definitions of exactly such a 'wireless
        dream system' were to do, I could perhaps cobble something up
        that would be extensible.

        Effectively, the system I'm working with is a single-master,
        multiple-slave system, which would be ideal for what we're
        doing.  To avoid interference from other sources, we would
        have to use secure encoding, along with timing, to ensure
        safety (i.e., a secure code to arm the system, system disarms
        if it either times out or loses signal from the master, etc.).

        If we design a modular system (i.e., a relay box with
        batteries for doing the actual firing, and a 'receiver
        section' that handles the wireless and intelligence, we should
        be good to go. Current systems (as I envision them using these
        components) would require a PC to act as the launch
        controller.  If we really wanted to, we could simply build a
        wireless box that 'looks' like the current launch controller,
        but sends the proper signals via the wireless master -- but
        I'm just kind of thinking out loud...

        What might be the more difficult aspect (possibly) would be
        the continuity detection (wirelessly), as we would need to
        have the circuitry in the range-head box to 'tell' the
        wireless unit if continuity was present, etc.  And this
        circuitry would need to work in conjunction with the current
system of the push-button/buzzer for the pad area itself. We'd also need to ensure that we can handle the wider-range of
        igniter firing levels (like the new Quest igniters) with such
        a system..

        Love to hear what other folks might think...

        David Erbas-White

        **Wireless System:**

        These types of systems (particularly multi pad systems) are
        just being developed and there's not a lot of experience
        using them.  If we had to obtain a new system today, I would
        suggest a wireless system because of the savings on the
        weight and cable cost.  But we don't need a new system
        currently, so let's see what's developed over the next couple
        of years and listen to their experiences.  In the meantime,
        we can save for a system so when ROC's ready, we'll have the
        money for a safe and reliable system.

        For me, my 'dream system' would look something like this:  A
        small control box would be located at each launch pad that
would be the receiver for a computer based wireless system. The LCO would launch rockets using a computer and daylight
        monitor connected to a powerful (over 2,500' range) wireless
        transmitter.  The pad control box would have a shunt
        and power switch controlled by the person loading the
        rocket and be located on a ground stake that would also have
        the pad number sign.  There would be both audible and visual
        arm signal on the box and it would also have a connection for
        a larger battery if necessary (i.e. more firing amps).  So,
        no central control boxes, just place the launch control box
        with the pad number sign were you want a pad, attach the
        launch leads with clips, and away you go.  This would allow
        for any kind of spacing on rows.

        Richard Dierking

        -- ROC-Chat mailing list roc-chat@xxxxxxxxxxxxx
        <mailto:roc-chat@xxxxxxxxxxxxx>
        //www.freelists.org/list/roc-chat



Other related posts: