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Open Propeller Project #2: Envision the S3 Robot — Parallax Forums

Open Propeller Project #2: Envision the S3 Robot

Ken GraceyKen Gracey Posts: 7,386
edited 2015-04-29 18:44 in Robotics
Attachment not found.
The S2 robot is one of the finest products Parallax has ever produced. Parallax has sold over 17,000 S2 robots and it’s quite popular in education from middle school through university. Those who have never worked with an S2 might discount it as a toy due to it’s humble physical appearance; those who have used it are amazed at what’s possible with the high-resolution encoders and GUI programming environment.

Like any product, the S2 must be evolve to stay attractive. We’re at that point today - we have to make some decisions about improving the S2 design to become an S3 in order to time production with reordering.

Bringing an S3 robot to market would not be trivial. The design team is here in the USA with fabrication and QA/QC in Shenzhen, China. Test procedures, child safety testing, production jigs and molds must all be resolved with lots of documentation, even more communication, and a trip or two to the factory. WIth all of this in mind, design revisions must be determined and incorporated a year before we expect a new model.

Working backwards from the day our current supply is consumed, we’ve determined that our go/no-go design decision must be made by April and that the design revisions would be completed by this June. If we are unable to make the design decisions now, it'll be another year before we can visit this again.

As the S3 would be a 100% restriction-free open source design, we would like to obtain more community input before we make the go/no-go decision under an Open Propeller Project. That’s all we’re looking for - your input on what an S3 robot would ideally become.

These are the known improvements we would consider to specifying an S3:
  • S3 would be yellow. S1 was blue and the S2 is red.
  • GUI would need to be rewritten to accommodate a wider range of operating systems and hardware. We have strong interest in using MIT’s Scratch, Blocky, or Google's Chrome (which one is TBD based on many factors). We could also delay the GUI re-design for a year.
  • Bluetooth programming interface. Serial port would likely be retained for use with the BetterBots Fluke, unless their needs could be met inside the S3.
  • Formalizing the Neil Rosenberg tutorials into an introductory curriculum with more STEAM concepts.
  • Rechargeable battery, with accompanying mold changes and charge circuitry.
  • Openly accessible hacker port, by hatch removal.
  • Remove microphone circuitry for cost savings.
There are limitations to what we we can do. First, our primary design goals must be driven by our volume educational customers. Class-pack purchases drive our decisions, so I am inviting them to take a look at this thread. Next, we don’t want to mess with the mold design more than small inserts or material removal. The S2 molds cost $35,000 in hard tooling and machining and even more to design. Significant changes to the mold are not practical. And finally, we have to keep our target price at $129 to $149 - no more. We’d have less than $5-10 of additional Bill of Material costs allowed in our budget.

We would make the entire design 100% open, free of restrictions.

We are interested in what improvements you might like in the S3. By April we will be fully engaged in the new design, or. . .

Ken Gracey
Parallax Inc.
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Comments

  • ercoerco Posts: 20,244
    edited 2014-02-10 18:54
    Ken Gracey wrote: »
    Those who[/FONT] have never worked with an S2 might discount it as a toy due to it’s humble physical appearance; those who have used it are amazed at what’s possible with the high-resolution encoders and GUI programming environment.

    Capital idea, Ken. I don't have any technical input yet (other than an exposed hacker port and breadboard area), but from the get-go, I would consider a higher-tech color than yellow for S3. That will really scream "toy" even louder than blue or red did. I actually liked the dark red S2. But if you went for black/gray/graphite, it would look more serious out the gate. And believe me, black (dark colors in general) are cheaper to produce than bright colors. Carbon, regrind, anything can go into black and nobody's the wiser, whereas bright colors often require expensive virgin material.

    Calling it carbon or graphite even sounds cool. Plus, no secondary black spray ops required to make the plastic IR-proof. They were required on S2.
  • WhitWhit Posts: 4,191
    edited 2014-02-10 19:34
    Ken,

    I love the idea too! Here are a few preliminary ideas. I will try to think more on it too.

    In a teaching environment it would be great to have a Volume Control in the GUI.

    What about a jack for the Veho Speaker or Microphone to the surface - could this be done cheaply?

    Could the GUI toggle with C or the Simple IDE (Spin too if desired).

    Having direct mini USB would really save keeping up with adapters (guess the Bluetooth is to address this concern?) - but might be too expensive and I do like the continued support of the Fluke.

    Love the hacker port being accessible with a hatch.

    I would love to see an add-on plastic universal attachment to go in the pen port – for PING))) Mounting Bracket Kit or Veho 360 Speaker or a Bread Board.

    Starter holes in the chassis for Dual Ping/IR Acrylic Stand with Sensors, Acrylic Ping))) Stand with Hardware, or Acrylic IR Stand with Hardware. Accessories and add-ons might allow other educational activities with out adding the cost of the basic S3.

    I also second the idea of gray or black (I know that may not be an option) - but I too think it would be less toy like.

    Colored O ring "tires" could make the wheels cool too!

    Possible other add on could be a pen lifter accessory.
  • Duane DegnDuane Degn Posts: 10,588
    edited 2014-02-10 20:09
    I really like the S2. To me the most annoying "feature" of the S2 is the level shifter circuity. As you're aware it interferes with using a Ping with the S2. I personally don't see an advantage to having it. The vast majority of 5V devices will accept 3.3V logic and a 10K resistor will make any 5V input safe for the Prop. I think my ultimate hacker port would have 10K or 4.7K resistors in line with the port. I'd want these resistors to be able to be bypassed (probably with a jumper). While most 5V devices will accept 3.3V logic, they won't do so if there's a large value series resistor in line.

    A less significant annoyance was having to remove the lid to access the hacker port. Making this easier to access would probably eliminate this concern. I know I've stripped out the sockets where the self threading screws engage the plastic. When I've previously thought of S2 upgrade one item on the list was some sort of metal nut for machine screws to engage. This machine screw and nut combo would allow repeated access to the insides of the Scribbler without stripping out the plastic. As I said, this isn't high on my list of improvement requests and it sounds like you're already taking care of this with an easier to access hacker port.

    I second erco's lack of enthusiasm over the yellow color. I like the red color much more than blue myself and I'm kind of sad to think of the red color going away. I think I like erco's black/grey idea but I'm not completely convinced.

    A couple other random ideas are:

    Add an IR receiver to make easier to control the robot with a TV remote. I'm not sure if this is very important if you have Bluetooth.

    An easier way of adding an internal pen lifter would be nice.

    I was pleased with how much adding an ultrasound sensor to the S2 improved its ability to detect obstacles. I'd love to see a built in ultrasound sensor but just making it easy to add one would probably be a good enough solution.

    I'd also like to see an easy to install pan/tilt mechanism to make it easy to add either the Laser Range Finder, CMUcam4 or the PropCam.

    It is exciting to think the super awesome S2 may be getting even awesomer.

    Did I mention I really don't like the level shifters?
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2014-02-10 22:20
    Whit wrote:
    In a teaching environment it would be great to have a Volume Control in the GUI.
    My first reaction was, "What? I thought there was one!" Then I realized that it was for the PC test playback only. Whit, would you want it to be a global control, or per sound tile?
    Duane Degn wrote:
    Add an IR receiver to make easier to control the robot with a TV remote.
    It's already there (assuming you can aim the remote at the front of the S2).
    To me the most annoying "feature" of the S2 is the level shifter circuity. As you're aware it interferes with using a Ping with the S2.
    I think this problem has been solved:

    But, yeah, the level converters are a pain. They work best with negative logic (i.e. systems that work with pull-ups, rather than with pull-downs like the Ping))) has). They're an imperfect solution, but there will always be tradeoffs with something bidirectional that also does level conversion.

    As to the color, I like yellow, but school-bus yellow or Fluke yellow -- definitely not lemon yellow which virtually screams WIMPY and ... well ... lemons, per the image in the first post. Yet, many equate the darker yellows, paired with black, as having an aura of ruggedness, which the Scribbler manifests quite well, IMO. Here is a photo montage, showing what I mean:

    123_003.jpg

    rov2.jpg

    49112737.jpg

    BTW, two-tone (e.g. gunmetal gray and black) are probalby out, gvien tthe economics of the one--shot injection molding process.

    I would hate to see the microphone go away. It is, frankly, one of the S2's more under-utilized features but could be a star performer given the right programming (e.g. voice commands).

    -Phil
  • Duane DegnDuane Degn Posts: 10,588
    edited 2014-02-11 00:27
    As to the color, I like yellow, but school-bus yellow or Fluke yellow -- definitely not lemon yellow which virtually screams WIMPY and ... well ... lemons, per the image in the first post. Yet, many equate the darker yellows, paired with black, as having an aura of ruggedness, which the Scribbler manifests quite well, IMO. Here is a photo montage, showing what I mean:

    You're winning me over to the yellow camp.

    I remember Jacques Cousteau had some really cool looking diving gear which was yellow and black. I couldn't find a picture of the gear but I did fine this "Yellow Submarine".

    [IMG]http://upload.wikimedia.org/wikipedia/commons/thumb/6/69/Подводная_лодка_Жака_Ива_Кусто_IMG_4571.JPG/640px-Подводная_лодка_Жака_Ива_Кусто_IMG_4571.JPG[/IMG]

    And the saucer shaped one.

    320px-Flying-saucer.jpg

    Which made me remember one of the coolest looking vehicles ever.

    [IMG]http://www.fantastic-plastic.com/FLYING SUB SIDE.jpg[/IMG]

    I think I'm warming up to a yellow Scribbler.

    Maybe the S3 could have a couple of strips of black tape running down it in a similar fashion to the flying sub.

    I thought of a few more feature requests on the S3. It should be able to fly and travel underwater.
  • WBA ConsultingWBA Consulting Posts: 2,933
    edited 2014-02-11 01:01
    Ken,
    I think the S2 is a fantastic platform for STEM/STEAM programs. The GUI programming software is a key feature for marketing the S2 and I feel that it allows you to lower the minimum age for such a versatile and powerful platform. Anyhow........

    Some comments
    • S3 would be yellow. S1 was blue and the S2 is red.
      • I think that Yellow only works if it is racing yellow with black stripes
      • yellowstang.jpg
      • As others mentioned, a graphite or carbon color would be a nice touch.
    • GUI would need to be rewritten to accommodate a wider range of operating systems and hardware.
      • Keep the look and feel of a drag and drop interface. That is the main reason I am using the S2 to teach my daughter robotics. Even though the S2 page says it's for ages 12+, I think the GUI is ideal for an 8 year old.
      • Bridging the GUI with another common language or programming is a good idea as long as efforts to do so can be accomplished swiftly.
    • Bluetooth programming interface. Serial port would likely be retained for use with the BetterBots Fluke, unless their needs could be met inside the S3.
      • I would recommend a USB interface as the standard connection for programming
      • Having an internal connector for a standard bluetooth module could make it easy to add bluetooth if desired, but as cost is a concern, USB should be first as not all potential buyers would have bluetooth available on their desktop or laptop.
    • Formalizing the Neil Rosenberg tutorials into an introductory curriculum with more STEAM concepts.
      • Very good idea. While the GUI is fantastic and easy to use, additional tutorials in a standard format will allow cleaner migration into school programs that are looking at other available options that already have associated curriculum offerings
    • Rechargeable battery, with accompanying mold changes and charge circuitry.
      • Adds cost, but would be preferred by many, especially if the charge circuitry runs from the same USB port as the programming interface.
    • Openly accessible hacker port, by hatch removal.
      • Excellent idea, but as mentioned by others, dump the level translator. If that is needed, many level translator breakout boards are readily available from Sparkfun, etc, for hacking in easily.
    • Remove microphone circuitry for cost savings.
      • Understandable, but if the Propeller has abilities in the audio arena, shouldn't it be left in and appropriate lessons be established for it's use?
    • Open Source
      • Please make the raw files that can be modified available for the Scribbler. As on this thread, eDrawings files are available, but editable files that can be converted to Sketchup, Draftsight, or other free applications would benefit open source S2/3 based initiatives by others.
    • STEM/STEAM programs
      • Some analysis of existing robotic platforms currently used by schools for STEM should occur so that design efforts suit your key intended market.
      • Speak with teachers that have already chosen a robotic platform and ask them how they arrived at their decisions.
    • STEM Marketing and Competition (brainstorm idea: how will the S3 stackup to these)
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  • Roy ElthamRoy Eltham Posts: 2,996
    edited 2014-02-11 03:02
    I think the reason Ken want's it to have BlueTooth is so it can be programmed using an iPad because a lot of schools have those I guess (note the open propeller project #1).

    I like the idea of a black or grey/graphite color a lot more than yellow.

    I really wish old school serial would go away already. No device in my house has it except my S2.

    I personally have no use for the graphical programming things, although I understand the need. I just hope there are some C libraries made to expose everything so I can code it use SimpleIDE/propgcc (similar to the ActivityBot stuff), I'd be willing to help with that effort, but my time is pretty well booked lately, maybe in the future.
  • NikosGNikosG Posts: 705
    edited 2014-02-11 06:16
    What news!!!!

    The S3 seems very promising!!!!
    The Idea of using MIT’s Scratch sounds Amazing for teachers and students!
    If we could use Scratch with S3 we could also Run Logo language commands and Geometry easily !!!
    Many teachers worldwide use Scratch and also some online programming environment like the famous Learn.code.org introduce programming techniques using environments like scratch (activities with the artist are similar to Logo). The commands blocks are like scratch and very similar to the GUI commands philosophy. S3 will be the next step for all of them and a real example from the screen to the real world!

    So my suggestions for the upcoming S3:

    Hardware:
    1) Wireless communication (any type) in order to execute commands in real time
    2) Pen lifter. (at least an appropriate chassis modification that can accept a mini servo connected into the hacker port for pen lifter use) and of course an appropriate gap on the pen tunnel in order to can accept the pen lifter movements.

    Software:
    1) Easy Logo language connection.
    2) Scratch connection. Or a similar programming environment able to do a simulation of the robot movement into computer screen.
    3) GUI changes: pen Up Pen down commands, ability to define directly local turns 0 to 360 degrees without to do extra calculations of time etc.

    P.s. combination yellow and black looks very aggressive and sportive! Will definitely like to the students!!!

    edit: Here is what I mean with chassis modification:
    An internal plastic extension in order to hold a mini servo and lower the pen tube
    attachment.php?attachmentid=106834&d=1392145750

    attachment.php?attachmentid=106835&d=1392145755

    Reduce the length upper pen tube 12mm (You can use the plastic that you gain from this conversion in order to make the extension for the mini servo)

    Give also with the optional mini extra mini servo a plastic “lift cup” like this:

    attachment.php?attachmentid=106836&d=1392146934

    You can avoid "lift cup" giving even a meaningless tie connected to the servo horn

    With this option you have the pen lifter as an optional accessory easy to install (no modifications only an extra mini servo). So you can keep the low cost!
  • WhitWhit Posts: 4,191
    edited 2014-02-11 07:05
    @Phil,

    As you know, the volume of the S2 can be controlled in Spin. I would like to be able to control it in the GUI. You may remember this proposed "sketch" for volume control in the Sound Tile that I did early in the S2 life. See lower right... Could be nicer, but this is the idea...

    Sound Tile.png

    If we are going with yellow - I love the Fluke Yellow Idea - epsecially with matching yellow O ring tires....

    Still love the idea of add-ons for pen lifter - Imagine a device shaped to go over the pen port with a cable that could plug into the hacker port. Up and Down pen in the GUI is a great idea Nikkos! Could have a note that this is avaliable with accessory number so and so. Same idea with a bread board experimentation area or Ping - open the hacker hatch and plug in to power.

    It is fun thinking of all the possiblities. The S2 is so great. An improved S3 would be a formatible robot.

    I also wondered about something (IR emitter) on the rear to allow S3s following one another.

    It would be great to do some more with the bar code scanning idea. (this is really just a tutorial issue though).

    I second the Level shifter concern. It ought to be easy to add other Parallax products, like Ping...

    Another great accesory would be remote control - with tutorial. Using erco adaptation for old Blue was one of my students favorites. This is not hard for the S2 either as is - It is something that could be done with a tutorial test alone...

    If we are updating the GUI - some New sounds (even some verbal feedback voice messages might be fun - Hello!, S3, Stall!, Good-Bye!, others?) I too kinda hate to see the mic go - but if we had a plug in option... I loved the recent record and playback thread.

    I would like if the rechargable batteries were removable so you they would not make the S3 unusable while recharing. Extra batteries and an stand alone charger could be accesories. One set and a charger could come with the S3. Or I guess it could run on regular batteries too.
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  • dgatelydgately Posts: 1,621
    edited 2014-02-11 07:58
    Ken,

    The requirement for Bluetooth should be upgraded to Bluetooth LE. If the intent is to communicate and/or load software from an iPad or other iOS device, BTLE support will be needed. Android devices are quickly 'absorbing' support for BTLE as well and can benefit from the upgrade. (I'm not trying to support an idea that only iOS devices should be used for communicating to the S3, just pointing out the lowest level of support required for a cross-platform solution).

    In keeping with the ActivityBot progress towards WiFi communications with computers, tablets and phones should the S3 support an XBee type interface? That would allow Bluetooth LE or WiFi communication to/from the bot in the future.

    Of course, currently there are no commercial XBee-type Bluetooth LE boards that I know of. I had to hack an HS-06 (BT 2.0) XBee adapter to accept an HM-10 (BTLE) module for my iPad-To-ActivityBot project. Would Parallax need to develop its own BTLE solution?


    dgately
  • ercoerco Posts: 20,244
    edited 2014-02-11 08:20
    Yellow? C'mon guys... stealth graphite is in. Plus a limited edition chrome model (vacuum metalized). Admit it, you'd buy an extra Terminator edition S3 just to put on your trophy shelf. And a transparent/clear X-Ray edition S3 would be the bomb, but for the IR-proofing previously mentioned. Polishing the molds for real clarity costs extra, and we'll pay extra.

    stealth+fighter+jet+%25285%2529.jpg

    attachment.php?attachmentid=106822&d=1392136169
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  • mindrobotsmindrobots Posts: 6,506
    edited 2014-02-11 08:33
    All of these suggestions sound great for an already wonderful robot platform. My only concern about Bluetooth; not everyone (me) might want the extra cost of Bluetooth on every S3 robot.

    Anything you can do to make options modular and expandable would be great. There's also probably a relatively good revenue stream in well integrated accessories.
  • dgatelydgately Posts: 1,621
    edited 2014-02-11 08:59
    erco wrote: »
    Yellow? C'mon guys... stealth graphite is in. Plus a limited edition chrome model (vacuum metalized). ]

    Better yet, "cloaking feature" :cool:

    dgately
  • mindrobotsmindrobots Posts: 6,506
    edited 2014-02-11 09:04
    erco wrote: »
    Plus a limited edition chrome model (vacuum metalized). Admit it, you'd buy an extra Terminator edition S3 just to put on your trophy shelf.

    Oooooh, the S3 - STEM-inator!! I'll buy one.

    Actually, the transparent ones would be cool for education - like the "old" visible-V8 and visible person models. Great "how does it work" models for the younger set!
  • WhitWhit Posts: 4,191
    edited 2014-02-11 09:21
    @erco,

    What?!?! No artificial plastic wood grain?
    thumbnail.jpg
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  • jazzedjazzed Posts: 11,803
    edited 2014-02-11 09:24
    Hi Ken,

    Parallax should consider an XBee connector for things like Bluetooth, Bluetooth LE, S6B Wifi, or XBee (even a USB serial module LOL). USB on board would be cheaper than a module of course, and the connection can be switched or jumpered for connecting Propeller's serial pins from USB to an optional XBee adapter.
  • Duane DegnDuane Degn Posts: 10,588
    edited 2014-02-11 09:38
    • Rechargeable battery, with accompanying mold changes and charge circuitry.
      • Adds cost, but would be preferred by many, especially if the charge circuitry runs from the same USB port as the programming interface.
    Whit wrote: »
    I would like if the rechargeable batteries were removable so you they would not make the S3 unusable while recharging. Extra batteries and an stand alone charger could be accessories. One set and a charger could come with the S3. Or I guess it could run on regular batteries too.

    I use rechargeable batteries in all my robots but the addition of an in robot charge circuit isn't high on my priorities.

    I don't mind using NiMH cells in the S2.

    What sort of rechargeable batteries are being considered?
    Roy Eltham wrote: »
    I really wish old school serial would go away already.

    I wish new school USB would go away (sort of). It's easy to add a second uC to to the S2 by using the S2's serial connection. If the Scribbler had a USB connection instead of the serial connection, the companion uC would have to be a USB host device (or use the hacker port).

    As much as I hate the lack of easy to interface serial connections on devices I do begrudgingly agree it would be a good idea if the Scribbler had a USB connection. A companion uC could be added using the hacker port.

    I think an on-board USB connection would make the Scribbler much more attractive to schools. I personally would rather keep the serial connection the way it is on the S2 but I think Parallax would be able to sell more S3s to schools if it had a USB port.
    Whit wrote: »
    As you know, the volume of the S2 can be controlled in Spin.

    I personally don't use the GUI much. When I do use it, I mainly use it to generate code to produce sound. The sound making ability of the S2 is a really fun feature. I agree with Whit about making the volume control available on the GUI. It would be nice if the volume control could be actively changed based on sensor input.

    I've personally never used the mic on my S2 but I've always been glad it had one. I keep intending to use the mic in a S2 project and I'd be sad to loose it in the S3.
    Whit wrote: »
    I also wondered about something (IR emitter) on the rear to allow S3s following one another.

    I like this idea.

    I really think another IR receiver should be added so the Scribbler could be controlled with ubiquitous IR remotes. (Yes, I know there's one on the front, but it's not very practical to use it as a IR remote receiver.)
    Whit wrote: »
    Another great accessory would be remote control -

    It would be really nice if a cheap IR remote could be used with the Scribbler and not just expensive Bluetooth devices.

    An IR receiver wouldn't be too hard to add through the hacker port but I think a permanently installed additional IR receiver would be a positive addition to the Scribbler's standard hardware.
  • W9GFOW9GFO Posts: 4,010
    edited 2014-02-11 10:00
    Despite there being some fine examples of where yellow works well, I do not think this is one of them.

    Graphite/grey, silver or white would be my preference. A limited, collector's edition of clear would be really cool too. Explore the possibility of making the two halves contrasting colors.

    I'd like to see the hacker port have 5V and 3.3V rails, with 800 - 1,000 mAh each.

    Upgrade to quadrature encoders.

    Add XBee socket.

    Add pen lifter!

    Keep battery compartment the same but add 2.5mm jack to shell for charging.

    A 360 degree visible IR receiver would also make beacon navigation easier to implement.
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2014-02-11 10:14
    W9GFO wrote:
    Upgrade to quadrature encoders.
    Rich,

    Can you cite an example where this would have been necessary -- or even helpful?

    -Phil
  • ercoerco Posts: 20,244
    edited 2014-02-11 10:23
    Another cool option is a translucent white (or frosted clear or very lightly silvered) outer case with several internal programmable RGB LEDs so you can illuminate the bot from within and make it any color you want: http://www.youtube.com/watch?feature=player_detailpage&v=FavhtC2Sh4s#t=18

    Also, a Knight Rider LED array is useful both for visual effects and also as an output display: http://www.youtube.com/watch?v=sm8K6dI8niA and http://www.youtube.com/watch?v=F8fKZ4A6mto

    IMO, it's high time to add several external switches or buttons to the S3. Could be bump switches or capacitive touch pads, which are cool, cheap & magical. This touch demo consistently wows at robot club meetings: http://www.youtube.com/watch?v=3e92B8JNNns
  • KMyersKMyers Posts: 433
    edited 2014-02-11 10:38
    I like all the above ideas esp the graphite gray color. Perhaps I missed this but what about a sd card? Would the Prop be something like the Activity board with perhaps a larger breadboard area? I also like the idea of add on accessories at my convience.
  • Duane DegnDuane Degn Posts: 10,588
    edited 2014-02-11 11:56
    Ken Myers' comment about the breadboard reminded me that adding a breadboard has been mentioned several times.

    I don't know if these suggestion are for an internal or external breadboard. I don't know if there's enough room inside for a breadboard so if one is added it would need to be external.

    I'm personally adamantly against adding an external breadboard. One of the really cool things about the Scribbler is its sleek look. I've noticed many of the people adding hacks to the S2 are very careful to keep the additions inside the S2's body. All of the suggestions to add a pen lifter have been to make it internal. I think an external breadboard would be ugly. Please don't add one.

    I don't know how many of you have been asked while showing off a really cool robot if the robot has a cover to hide all the wires but it has happened to me many times. It's really kind of odd how much exposed wires bother so many people.

    One of my hacks was to add a Propeller to a Roboni-I robot. I changed the LEDs from bi-colored to RGB and made it drive nice and smooth without its normal rocking motion. If I ever try to show off these changes without replacing the top piece of the body, I'm nearly always interrupted in my demonstration with the question "it has a top piece to hide the wires right?". It can be very annoying to see how much more important a sleek looking robot is than a robot with all sorts of cool features which happens also to have dangling wires.

    I think keeping the exterior of the Scribbler looking sleek and clean should be a very high priority.
  • mindrobotsmindrobots Posts: 6,506
    edited 2014-02-11 12:24
    Duane Degn wrote: »
    I think keeping the exterior of the Scribbler looking sleek and clean should be a very high priority.

    +1 on no breadboard!!

    If you want to stick a breadboard on the outside, most of them have double sided tape. Slick is a good look to have out of the box.

    Is it possible to create a molded spacer that fits between the 2 halves of the shell to add an inch to the height without major retooling? That would give more interior space and possibly let you run the S3 "topless" like Gareth's latest creation allows. Now, if you want to go topless, your motors flop out. (hate when that happens!!
  • KMyersKMyers Posts: 433
    edited 2014-02-11 13:20
    Dont want to start a holly war on this as it is trivial. For me with limited mobility and use of arms it would be more useful to me and I would use it more then I do currently. Appearence is seconday to ease of use IMHO...
  • W9GFOW9GFO Posts: 4,010
    edited 2014-02-11 13:32
    Rich,

    Can you cite an example where this would have been necessary -- or even helpful?

    -Phil

    I think it would be good to be able to use existing quadrature encoder objects for programming. Quadrature encoding is a pretty basic robotics concept, should be able to use it on an educational robot IMO.

    I would like to be able to manually push the S3 around and have it store it's path.

    Also, I would like to see the S3 move faster, it is currently quite a bit slower than the original Scribbler and it wasn't fast either. Faster motors would mean a lower gear ratio, which would mean that the wheel would more easily be moved when the motor was idle losing track of it's position. This is unlike the S2 which has such a high ratio that it takes quite a bit of force on the wheel to get the motor moving - which of course means that there is no nead to keep track of encoder counts because you can count on it not moving.
  • NikosGNikosG Posts: 705
    edited 2014-02-11 13:57
    Duane Degn wrote: »
    A less significant annoyance was having to remove the lid to access the hacker port. Making this easier to access would probably eliminate this concern. I know I've stripped out the sockets where the self threading screws engage the plastic. When I've previously thought of S2 upgrade one item on the list was some sort of metal nut for machine screws to engage. This machine screw and nut combo would allow repeated access to the insides of the Scribbler without stripping out the plastic. As I said, this isn't high on my list of improvement requests and it sounds like you're already taking care of this with an easier to access hacker port.

    I second Duane’s’ concern about the screws.
    You can change them with longer that pass up to the top part of the chassis. ( I ‘ve already made this modification with one of my S2 s and it works perfect!

    attachment.php?attachmentid=106840&d=1392155670

    With this solution you can also add the intermediate extension (optional frame) between top and bottom part of the chassis in order to give more space for those who want additional internal changes. The only you have to do if you add the intermediate frame is to put longer screws.

    attachment.php?attachmentid=106841&d=1392155673

    Longer screws must pass trough bottom, intermediate and top parts of the chassis.
    797 x 696 - 178K
    695 x 585 - 88K
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2014-02-11 14:12
    W9GFO wrote:
    Quadrature encoding is a pretty basic robotics concept, should be able to use it on an educational robot IMO.
    A quadrature encoder is useful when the system doing the sensing is divorced from the systems doing the driving. It's not really necessary, though, when you already know which direction the motors are turning. I haven't seen a case where having them would improve the accuracy of drawing, for example. Even with a lower gear ratio, I doubt that the bot would roll on even the steepest incline when idle. And it would use up two more port pins, of which there is no surplus, unfortunately. So it's a tradeoff: when you claim additional port pins for a function, you have to ask how much value it adds, compared to using the same pins for something else.

    As to metal thread inserts for the case screws, I would say definitely yes. Half of my plastic threads are stripped, and the case is barely hanging together.

    -Phil
  • ercoerco Posts: 20,244
    edited 2014-02-11 14:31
    W9GFO wrote: »
    I would like to be able to manually push the S3 around and have it store it's path.

    That would be a very demonstrable feature. LEGO has something with two motors that records and plays back motion sequences. For S3, two quad encoders (to get direction information) would require four sensors instead of the current two. I wonder in lieu of doubling the sensor count, could you get an ADC voltage reading from each motor output while pushing to determine direction of rotation?
  • Roy ElthamRoy Eltham Posts: 2,996
    edited 2014-02-11 14:39
    If pin availability is a problem, why not use a shift register to expand it? This would allow more controllable LEDs and more inputs for encoders and buttons/bumpers.

    I'm currently working on software for a pinball controller project that has 8x 595s and 8x 165s to allow for driving 32 mosfets, a few 7 seg displays, and several servos, and reading 64 switch inputs. They share clock and latch pins (it's only 4 pins total), so I talk to them at the same time. Obviously, S3 doesn't need that many of them, but it might be worth considering.
  • W9GFOW9GFO Posts: 4,010
    edited 2014-02-11 14:40
    I haven't seen a case where having them would improve the accuracy of drawing, for example.

    The coordinate system is integer only, so a quadrature encoder would increase the resolution by four. That should mean more accurate circles due to lessening the effect of rounding.
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