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S2 Robot: include a serial cable or not? — Parallax Forums

S2 Robot: include a serial cable or not?

Ken GraceyKen Gracey Posts: 7,392
edited 2010-10-19 13:01 in Robotics
Hey there,

Parallax is just about ready to send the S2 robot to production. We're making the final changes to the Start-up Guide and box sleeve packaging, the last steps of the process. There's a tremendous amount of engineering in this new robot that you will appreciate. Phil Pilgrim and Ben Wirz have been busy for a year on this project. Simply put, the Propeller enabled a far more capable bot with concurrent processing. And loosing the marketing angle towards children gives us a faster, straight-traveling, louder robot. Oh, and the hacker port!

http://www.parallax.com/ProductInfo/Robotics/TheScribbler2/tabid/826/Default.aspx

You may benefit from a bit of background on the business side of this robot to answer the question. We've sold over 10,000 blue Scribblers - yet all of the gross profit has been poured into S2. The R&D, tooling, and NRE costs associated with S2 are significant, and the Bill of Materials cost has increased substantially. We're doing our best to make this a $99.99 robot - but we're operating on some pretty thin margins. Every penny counts, but we won't cut costs on quality or components.

But we're stuck on a specific issue - whether or not to include the serial cable. The S2 is programmable right out of the box by covering specific photoresistors or using the reset button to select a program. A fully tested serial cable costs about a dollar.

We suspect that many people who buy S2s will use USB to serial adapters, either from Parallax or elsewhere. And others probably have serial cables laying around already.

We didn't put the USB to Serial adapter in the S2 because most of our customers have this part and because it raises the bill of material cost to everybody but benefits only a few. We'll offer a version on-line that includes the USB to serial adapter, for $10 more or so. Our USB to Serial Adapter includes the USB cable. Customers who buy from Fry's Electronics would have to read the box to see that a USB to Serial converter is required for GUI or code-based programming.

It wasn't practical to design the USB to serial converter into the S2 due to cost (in components, significant mold modifications, etc.). I am certain this would have pushed the price to $129. And our biggest volume customers in education need the serial port for their Fluke. So the DB-9 remains.

On the surface it appears that the serial cable would simply contribute to landfills. Sounds like we've already made our minds up, but it's not really the case.

The CD has been omitted from the S2 packaging, by the way.

The market for S2 is schools, hobbyists and engineers. That's right - everybody!

Share your opinion, please.

We'll read the replies but I may not have time to answer all of them.

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Comments

  • schillschill Posts: 741
    edited 2010-08-12 12:31
    I can see there being a real issue with not wanting to have buyers disappointed when they find out (too late) that they need to get a cable.

    But these days, many (most) of those buyers probably won't have serial ports on their computers (especially with so many people moving to just using laptops) so a serial cable would probably just end up in a junk drawer or landfill [1].

    I guess I'd say it should probably be a USB cable or nothing. As long as you are making one available (and it's clear when people are ordering) then there shouldn't be any real problems. If you can get Fry's and other retailers to prominently display the USB/serial cable with the robot that would be good. It would be good if you have a recommended cable that can be sold with it - especially if it's one you will support. In the past, I've certainly had mixed results with generic USB/serial cables (resulting in my refusal to use anything that didn't have and FTDI chip in it (because I knew they would always work for me) but I've eased up a little on that). By recommending a cable, you may be able to avoid problems later.

    It should be fairly clear on the packaging that it is not included - but somehow it shouldn't make it look like you are making people buy a lot of extra stuff (stuff that they will think should be included).

    [1] I, on the other hand, don't mind having extra serial cables around. The main computer I use (for development, photography, whatever...) only has 6 serial ports, but an extra cable never hurts :) . I think I only have one (very, very old [2]) laptop left around that has a serial port.

    [2] W/ a 486 DX2/50
  • SSteveSSteve Posts: 808
    edited 2010-08-12 13:49
    It should be very clear on the front of the box that a serial cable or USB/Serial converter is required. It would be very frustrating to get home (or, worse yet, have Sally open her present on her 15th birthday) and realize that you can't do anything because you don't have the right interfacing.

    Even with a big warning, you should be prepared to send out some free cables or USB/Serial converters to make some disappointed customers happy.
  • ZootZoot Posts: 2,227
    edited 2010-08-12 14:05
    If you can package an order with or without, that would be best. In these times, everyone wants to save money, but you don't want anyone being stuck "out of the box".

    Ideally, the S2 would be offered in three ways (with the "extras" packaged separately, not necessarily in the S2 box proper):

    Plain S2 (no cables, no adapters)
    USB S2 (includes USB cable and USB to Serial adapter)
    Serial S2 (includes serial cable)

    This way folks get what they need, and don't have to pay an extra $5 or $10 or $15 dollars unless it's something they need, and Parallax isn't stuck with an even thinner profit margin on each unit sold.

    The trick, as Ssteve and schill wrote, is making it crystal clear to the buyer that cables are NOT included with the "plain" S2, and getting vendors other than Parallax to sell w/ and w/o accessories in a clear way.

    I would add that my kids all have laptops with serial ports. Why? Because they get the old laptop hand-me-downs, not new ones. And certainly many schools have computers of various ages and configurations. Classroom computers, or those used by Girl Scout robotics clubs, may also be donated hand-me-downs with serial ports.
  • ercoerco Posts: 20,256
    edited 2010-08-12 14:08
    I say ditch the cable, it's wasting a dollar. If the robot is prepreprogrammed to do SOMETHING right out of the box, as S1 was, then there's something for new users to do. As you noted, most of us have a dozen useless serial cables already and computers without serial ports. Most buyers will have read all about S2, but even if the buyer knows nothing about the cable situation, odds are that he needs a USB adapter.

    So take that dollar and plus up the robot, or put it right back into the S3 development fund. I'm certain that PhiPi already has thoughts for the 3rd generation Scribbler. I'm guessing standard yellow plastic case, with LiPo battery, charging dock, laser rangefinder, HiFi WiFi Bluetooth Blackfin Webcam RoboRealm Northstar etc. And a gripper.

    All for $99. Now see to it!
  • Oldbitcollector (Jeff)Oldbitcollector (Jeff) Posts: 8,091
    edited 2010-08-12 14:12
    Getting a robot and then discovering that you need to get an additional cable to play is a real bummer. Surely this couldn't add more than .30 to the costs?

    Include the cable Ken, by the time these are released a bunch of them will wind up under some Christmas trees. No one wants to be short a cable on Christmas morning. :)

    OBC
  • TinkersALotTinkersALot Posts: 535
    edited 2010-08-12 14:43
    Can I change my vote to:

    Just make a decision, Parallax. I'm ready to order an S2!
  • John AbshierJohn Abshier Posts: 1,116
    edited 2010-08-12 14:49
    No serial cable. But make the requirement prominent on the box and on the web. Try to get resellers to make sure their customers know the requirements.

    John Abshier
  • W9GFOW9GFO Posts: 4,010
    edited 2010-08-12 15:47
    I think this is a real dilemma. Including the cable doesn't really solve the problem for the average user who has purchased it to learn some programming. They will need to get the USB converter as well.

    I also think that introducing a new product that does not use USB is a huge disadvantage. Maybe not to the education markets that need the DB9, but to everyone else who is new to this.

    I would urge you to take the extra time and figure out a way to incorporate USB into the S2. There must be a clever way to add a USB port without making new molds. Maybe make a small adapter to take the place of the DB9?

    Lots of customers are going to be disappointed to find that they need extra "stuff" to use it fully. People will be expecting it to come with a USB cable, just like everything else.

    Rich H
  • JeffaJeffa Posts: 80
    edited 2010-08-12 16:27
    Batteries are not included? It's not crystal clear on the data sheet. I assume not included. (Now one thing I have is a lot of extra RJ11 cables for modems...) I don't feel that not including the cable is an end all.

    The target market for this is probably first time users and will play and learn with it out of the box before deciding to go for the advanced topic of programming. If they decide they want to program a robot they've probably tried a few intermediate projects on their computer first and will have the serial cable and probably a usb converter too.

    Some thoughts after reading the thread

    It's probably not practicle to have more than one SKU on the product. On the other hand a second SKU could be the robot along with a printed copy of the manual, a pen and the serial cable and USB dohikie.

    FRY's and ?Radio Shack? may prefer the serial cable not be included for an upsell.

    Marketing spin: A small: "Notice: requires suitable USB interface for advanced programming" clearly visable on the front of the box would be preferable than "USB cable not included" in a 5 point font on the back of the box.

    c ya.... -jeffa
  • schillschill Posts: 741
    edited 2010-08-12 16:34
    W9GFO wrote: »
    I would urge you to take the extra time and figure out a way to incorporate USB into the S2. There must be a clever way to add a USB port without making new molds. Maybe make a small adapter to take the place of the DB9?

    It's not a cheap approach, but here's one way to replace the DB9:

    FTDI DB9-USB-RS232

    http://apple.clickandbuild.com/cnb/shop/ftdichip?op=catalogue-products-null&prodCategoryID=100&title=DB9-USB-RS232-F

    They will add a fair amount to the price and are not available yet (I don't think), but maybe Parallax can make it really easy to desolder the connector on the board :) .

    Edit: I was wrong. They are available. $17.00 each in lots of 100 from Mouser.
  • John R.John R. Posts: 1,376
    edited 2010-08-12 17:30
    Getting a robot and then discovering that you need to get an additional cable to play is a real bummer. Surely this couldn't add more than .30 to the costs?

    Include the cable Ken, by the time these are released a bunch of them will wind up under some Christmas trees. No one wants to be short a cable on Christmas morning. :)

    OBC

    I think the cost is closer to the dollar level, and that just for the serial cable. Keep in mind, that the S2 only has a 9 pin RS232 connection, so you have all that metal, plastic and pins to include, on both ends.

    What that also means, is that even if they include the serial cable at a buck, the poor kid is probably still going to be SOL on Christmas Morning due to a lack of USB to RS232 adapter.

    It just doesn't seem to make sense to include this stuff. This seems to fall into the same category as "batteries not included". Just make it clear on the box, maybe even with pictures, that you need a cable that can go from your computer (show a DB9 and USB port) to the S2. Show just a serial cable from the DB9, and show an adapter and cable for the USB port.
  • BeanBean Posts: 8,129
    edited 2010-08-12 18:14
    Ken,
    I haven't seen a serial port on a computer in years. Heck you can't even get a printer port anymore.
    The only thing worse than not getting a cable is paying for a cable that you cannot use.

    I say make it VERY obvious on the box that a cable is REQUIRED. Either serial or USB to serial.

    Bean
  • SeariderSearider Posts: 290
    edited 2010-08-12 19:33
    Personally, I am tired of getting USB and serial cables with things I buy. I have a box full of extra Serial and USB cables still with the twistie ties on. Please, reduce your carbon footprint and avoid extra cables that we don't' need. If for some reason a person needs it, they can buy what they need. Better to have 1 person buy a serial cable extra than have 10,000 people trash the serial cable they don't need.
  • Peter KG6LSEPeter KG6LSE Posts: 1,383
    edited 2010-08-12 23:54
    My only worries is the Port looks resesed to far to use a direct USB to serial adapter right on it with out a short DB dongle .

    I know On my HWB and BOE I had to remove the hex standoffs on all my BOEs and HWBs to be able to directly hook up my USB> serial adapter . I use a USB 19H from keyspan .

    You might want to include a gender bender to act as a riser .

    also I dont see any holes for the lock screws . not that you would need them in this application BUT some cables have CAPTIVE lockscrews and you can't just" back them out" or what not . so they need a place to go ..

    One time I had to snap off the screws on a VGA cable to put it on my dads old HP( DV600t) . It too had no threaded holes and the ones on the cable were captive. ...

    In the case of the S2 If It was My device to use I would hot glue a
    super short genderbender M>F on it to let me be able to use it with my adapters.

    Peter KG6LSE
  • GalacticaActualGalacticaActual Posts: 18
    edited 2010-08-13 11:48
    >
    > The market for S2 is schools, hobbyists and engineers. That's right - everybody!
    >

    If the purchaser is a school, I would think they probably already have a serial cable. If the school buys multiple robots, they probably don't need a serial cable for each robot.

    If the purchaser is a hobbyist, they probably already have a cable.

    If the purchaser is an engineer, they already have a cable.

    The purchaser who needs a serial cable is a new customer. You can put in the box a coupon for a discounted serial cable and/or usb cable and usb-to-serial adapter.

    I recommend leaving out the serial cable.
  • John R.John R. Posts: 1,376
    edited 2010-08-13 12:13
    Going back to the "Christmas Morning" thing, and the brand new user that has a new computer without any RS232 serial port on it:
    If you include a serial cable, you may make them more frustrated than NOT having a cable, as you included "a" cable, but it's the WRONG cable.

    Personally, I'd rather be short parts than think that some "idiot" put the wrong parts in the box.
    John R.
  • WhitWhit Posts: 4,191
    edited 2010-08-14 14:46
    I say do not include the Serial cable. I say this in spite of the fact that this year we had many computers where the USB port failed and the Serial cable (in the box of the blue Scribbler) saved our bacon!

    It should be clear that users will need the USB to Serial adapter or the Serial cable to program the S2 on the box and on the website. They can order what they want when they get their Scribbler 2.

    Anyone who has a choice though would probable want the USB cable and the USB to Serial adapter.
  • Kevin WoodKevin Wood Posts: 1,266
    edited 2010-08-15 03:33
    I would raise the price by $20, and include the USB2SER adapter and a USB cable for it.
  • Oldbitcollector (Jeff)Oldbitcollector (Jeff) Posts: 8,091
    edited 2010-08-15 10:04
    John R. wrote: »
    Going back to the "Christmas Morning" thing, and the brand new user that has a new computer without any RS232 serial port on it:

    John R.

    Hey John,

    the serial port is still alive and kicking.. (for now) All of the systems we build still have a single serial port on the motherboard. There's no LPT port as of this year, but still have a serial port. (MSI boards)

    OBC
  • Oldbitcollector (Jeff)Oldbitcollector (Jeff) Posts: 8,091
    edited 2010-08-15 10:06
    Looks like a slam dunk on the decision... Which is what Ken needed..

    /me runs off to run a serial cable to set aside for the S2. :)

    OBC
  • John R.John R. Posts: 1,376
    edited 2010-08-16 07:16
    Hey John,

    the serial port is still alive and kicking.. (for now) All of the systems we build still have a single serial port on the motherboard. There's no LPT port as of this year, but still have a serial port. (MSI boards)

    OBC

    Jeff;

    I would suggest that you're in the minority. I was just looking at about a half dozen Dell models, including "performance" PCs, and didn't find one with a serial port on it. (Not that Dell is the "be all, end all", but size does count for something.)

    Even harder to find on a laptop.

    I'd guess that our local "build your own" guys also still have serial ports, but what % of the market do these types of shops have, and are these consumers going to be the guys buying the S2, or are they more likely to be going with a BOE Bot or Sumo?


    John R.
  • ShirleyMShirleyM Posts: 1
    edited 2010-08-19 10:04
    I have a set of laptops and netbooks in my classroom. I would either use USB or program wirelessly.
  • EnTerrEnTerr Posts: 3
    edited 2010-08-25 13:18
    Of course you should include computer-robot cable in the box! You should also include a CD media.

    Do a cost-benefit analysis. How much will cable increase the cost by? 1-5%, depending on whether you include rs232 or rs232-usb cable.

    On the other hand, how many customers will be disappointed if they find out that the bot is useless out of the box and they need to procure a nowadays rare cable or even worse, deal with the fact that their laptop or desktop has no serial port whatsoever? I would say 50% of people purchasing that in store will be bummed out by that. Many of them will just return the toy back. Whoever thinks they'll keep $100 toy that only runs around the room and beeps like ambulance - you can't be serious.

    So is it worth to disappoint large % of buyers to save couple of dollars? You have to decide on that. It depends how you see your mission and target audience. Are you trying to win new robotics enthusiasts or are you selling this only for hobbyists that already have the previous version of Scribbler?

    Asking the question here - the Robotics forum of Parallax - is bound to give you distorted picture, unless you are targeting only people that already have some kind of BS* or Propeller board (and the serial cables for that). I too, have that equipment and it's not that i bitching on my own account.

    But what about wider audiences, "outsiders" that you would like to bring on board uC and robotics? Go to Frys, stand to the shelves with Tamiya toys or Lego Mindstorms and ask the people that stop and look at the items, that will give you idea of how the world outside is.

    Regarding the kind of cable - it is pretty clear to me you should communicate with it over USB. Hello, welcome to the 21st century! Mindstorms NXT, released in 2006, uses USB and bluetooth. Even the first version of Lego Mindstorms (1998) had choice of rs232 or USB for the IR tower that was used to connect to the brick.

    I understand your problem with IPRE Fluke being rs232 only but those guys will have to grow up at some point too. So a rs232-usb cable will be a good thing to include in the box, thus avoiding changes in Scribbler body and schematics. But isn't that too expensive? Not really:
    $5.40 USB 2.0 to RS232 Cable http://www.dealextreme.com/details.dx/sku.8757
    $5.50 USB to RS232 Adapter Cable http://www.dealextreme.com/details.dx/sku.30495
    $6 USB RS232 Cable http://www.dealextreme.com/details.dx/sku.622
    $3 USB to RS232 Adapter with USB Extension Cable http://www.dealextreme.com/details.dx/sku.24799
    $3.70 USB to RS232 Adapter with USB Extension Cable http://www.dealextreme.com/details.dx/sku.25273
    (those are retail prices with delivery from China - and i am already using one of these with BS2)

    Here is an idea: how about two different distributions, a $100 retail-store box with assembled robot and usb2serial cable and a sub-$100 distro, including only the BoM items, unassembled (no CD, no cable) - this one sold only online for enthusiasts that would like to assemble the bot from scratch? Personally I would be inclined to purchase such pack, without unnecessary (for me) extras like cable and CD and participating in final assembly of the robot will be extra perk. I disassembled and reassembled a Scribbler and it is easy/fun.

    PS. regarding the lack of CD included in the box - seriously? Nothing says "cheap" (as in inferior) as saving a few cents by not including another necessary part.

    PPS. btw why do you see only Frys as retail distribution - how about RadioShack, Microcenter and other chains?
  • Peter KG6LSEPeter KG6LSE Posts: 1,383
    edited 2010-08-25 14:05
    I would rather see a Good FTDI adapter and pay more then a cheap one with horrid SW support .
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2010-08-25 15:50
    EnTerr,

    There are more advantages to not including a CD than just the cost savings of the plastic, printing, and burning. By requiring users to download a product's software, those users are guaranteed to have the latest version with all applicable upgrades. Moreover, upgrades and bug fixes can be applied instantly, when they happen, not just when the current inventory of CDs runs out.

    I don't think I've ever bought software that included a CD that had the most up-to-date files. I've always had to download something else to get the current version. In almost every case, the inclusion of a CD with the product was a complete waste of materials.

    -Phil
  • EnTerrEnTerr Posts: 3
    edited 2010-08-25 16:15
    There are more advantages to not including a CD than just the cost savings of the plastic, printing, and burning. By requiring users to download a product's software, those users are guaranteed to have the latest version with all applicable upgrades. Moreover, upgrades and bug fixes can be applied instantly, when they happen, not just when the current inventory of CDs runs out.

    I hear ya - i too routinely check manufacturer websites for updates and fixes.

    But my point is to have a complete retail package which makes for Christmas gift as well - unwrap, pop batteries in and enjoy. Install software from CD, write programs. Simple scenario, no disappointments, having to run "the Shack" for cables or getting online (is internet down? is the web site "down for upgrades/backups"? did they moved the support URL etc - example - why does http://www.scribblerrobot.com/ which the manual tells me to go to for latest software - why does it give me "Service Unavailable" right now?!)

    There is nothing that time-sensitive to include on the CD - only IDE/compiler - the things that could change are sample programs - and the CD can always try to check online first before installing the software. And it will be a safe-haven to down-grade to in case a new downloaded version does not work
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2010-08-25 21:49
    EnTerr wrote: »
    There is nothing that time-sensitive to include on the CD - only IDE/compiler
    Oh, if "only" that were true! :) As it is, the programs and docs are still being updated and tweaked as the S2 goes into production. If Parallax were to include a CD, everything would have had to be "in the can" a long time ago in preparation for CD production and printing so they would be ready in time to load into the boxes with the robots. By not including a CD, there's just enough extra time available before the product's official debut to finish the software details in a manner that befits the S2's high quality standards. Trust me on this: the time it takes to do a download will be worth the wait! Besides, like the original Scribbler, the S2 will come pre-loaded with default demo firmware so it can operate right out of the box without even connecting it to a PC.

    -Phil
  • EnTerrEnTerr Posts: 3
    edited 2010-08-25 23:38
    By not including a CD, there's just enough extra time available before the product's official debut to finish the software details in a manner that befits the S2's high quality standards. Trust me on this: the time it takes to do a download will be worth the wait!

    Don't miss the part about http://scribblerrobot.com/ website being down - which it still is - one cannot afford to have retail package with no software accessible. If it had USB connection, i'd say include the software on flash drive in the robot but as it is that's SciFi.

    For those retail packages the CD is not available yet, there is a simple solution - postcard: "Mail this card back to us to receive free software CD in the mail"
  • John KauffmanJohn Kauffman Posts: 653
    edited 2010-09-14 17:43
    One of the problems I have encountered for the last few years is a lack of classrooms that have PCs with a serial port. And none of my student laptops have serial ports. In homes they are just as rare. I think the serial port on PCs should be considered dead in terms of new Parallax products.

    You noted that most of your customers already have the serial to USB converter and so including one would not be of use to most buyers. I would be surprised about that. If you are going to sell to gift-givers, hobbyists, newbies, etc. then I think you have to assume they will not have ser to USB converters. Or to put it another way, do you want your customers to be only Parallax insiders or do you picture this as a product to reach out to a much broader community? That broader pool of potential customers will not have (or even understand) a reference to the Parallax part number 28030.

    If I was going to sell this product I would consider a lack of serial port and a lack of converter as the normal for this market of buyers. Therefore the box should have everything needed to open and use with a PC that does not have a serial port. For the S2, I would offer two SKUs
    - Standard S2 ~$115 - that includes a serial to USB converter and cable
    - Special Edition S2 ~$99 - that is for more knowledgeable users that understand the situation and have a USB converter
    This is the opposite of what I think you wrote that you would make a second SKU available on the web site with the adapter.

    To summarize - make the S2 work out-of-the box with USB. That is the advertised product. In more limited marketing sell a second SKU for those that already own a usb to serial converter and only advertise that lower-priced option in contexts where the buyer is knowledgeable or you have the space to explain the situation.
  • Husky X3Husky X3 Posts: 18
    edited 2010-10-18 23:09
    Yes
    include a SER(RS232) cable. USB cables are cheap and we many already have them for their phones/PDA's/smartphones/cameras/etc. Those of us still using Serial ports would like to be included in the product consideration.
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