The G-bot (gwen's B9 Robot Project) Gets His First Test Outside Fully Assmebled


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Took the G-Bot outside for the first time with him fully built up... Nerve racking to say the least...

The bad new: He ended up off the driveway in a ditch tipping JUUUUSSSST shy of going over... wheww... The control is a bit unnatural due to the lag and the way the ramping seems to continue for a time after input stops. Add to that my driveway is uneven and mildly inclined plus, my notebook seemed to be working hard. There seemed to be a com delay too.

Note to self: Do not wear flip flops while experimenting with a 300 lb robot and NEVER get the front of one under a tread...

Note to self two: Get a wireless game controller and NEVER let the cord of the current one get under a tread... Very bad...

It was much better when I got him into our street which is level. One of my neighbors drove by and stopped next to him. The G-Bot escorted him down the street for a short bit... very cool.

The good news: He DIDN'T go over and my and my neighbors had some great fun!

I'll be doing some more tweaking and practice runs today. That should be fun and hopefully we'll figure out enough to get a few Trick or Treaters going on Halloween.


More video next week...


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Wow, that's one awesome bot Gwen! Thanks for sharing!

You'll likely have all the neighborhood kids at your place this Halloween:)


Gwen, Your robot is amazing! I am awed how well it moves for being such a big unit. The waist rotation is also great. Great action. I love looking at all the cool robots on this forum. It looks like so much fun, Halloween will be even more fun. Thanks for sharing, Steve S


I OMG Gwen. That's awesome! I don't know how you keep from freaking out when he almost tipped over. I would have soiled my undies and developed an ulster before I got him back in the garage. More proof that women are tougher than men. Well done! I'm jealous. I love the way he can turn 360 degrees and on the move too! I gotta get my big guy mobile now after seeing this.

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I'll take another look at the ramping code when I have more time, I'm sure it can be optimised somewhere which may reduce the lag you experience.

One thing I did think earlier about the script is I didn't use any control commands to stop the script when direction is changed or when the joystick returns to the centre. I don't think it will make much difference if any but that's at least one place to tweak it to make it better.

The lag may be due to the ramping speed sleep too, I'll have a look to see if it does introduce a lag and if it can be done a different way to avoid or reduce the lag.

Looks great though!


@Dave Shulpius the video IS heavily edited... I failed to mention that just maybe I had to change when I came in... Lol...

@Rich Any enhancements are welcome but PLEASE understand how GRATEFUL I am for what you've done thus far... You made it possible for me to meet my commitment to the local robot fans! THANK YOU, THANK YOU, THANK YOU!



Bummed I couldn't get the neon working for Halloween. The trigger circuit doesn't seem to be working anymore. I've tried a ground loop isolator, rewiring all the components to common power and ground, changing the frequency input range and tweaking the input sensitivity... No luck. The tubes and power supply are good. The neon will light but the trigger just won't do it...


Oh my gosh! You are going to have all the attention for Halloween. :) That is so awesome! He's really huge isn't he. I'd be scared of him toppling over too. But he made it!


Very nice, glad you got that big guy moving. So entertaining to watch !

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I just updated the project on the cloud to include a ScriptStop ControlCommand() in the Movement Panel direction scripts. I don't know how much (if any) difference it will make but the way it was before there wasn't anything saying "OK stop that running" before asking it to run again. If nothing else it's now written properly:)

Give it a whirl (if you merged the project with yours before and kept the script manager's name as I set it just remove your movement panel, merge with this new version and import the new Movement Panel - make sure you keep a copy of your project before doing it though, I'd hate for it to screw up the project and have no back up).

If you are experiencing lag with the new version (and probably the old version too) it is more likely to be the sabertooth and the speed ramping causing it, in which case there's not a lot that can be done. It should work without lag (at least in my tests without a sabertooth it updates everything near instantly), the only thing to watch out for should be the fact that stop doesn't immediately stop but ramps down so it may take half a second or so to come to a halt.

Touching on the safety features (i.e. anti-child run over, crashing, tipping etc) you could add in Ultrasonic sensors (@Toymaker has a good set up for these) and script it to monitor the distance to something, if it (rapidly) gets too close it shuts off the movement, similar to how these new cars work to make it impossible to have a low speed crash.


And Gwen brings us another episode of "lost in Gwen world"... lol

Great job, thanks for sharing...



I have a couple of the ultrasonic sensors that I bought with the EZ Robot kits. They'll definitely be in the next round of upgrades...

@Rich Thanks again so much for updating the code. I wont be able to try it out until the morning though.

I'll let you know how it works out :)


Gwen, Is your lag problem due to the need to use a script to simulate ramping? What version of the Sabertooth are you using? I was under the impression that the Sabertooth is able to ramp. I've never used the Sabertooth alone (without a Kangaroo attached for position and speed) but I've seen the setting in the DEScribe software. You need to attach your laptop to the sabertooth through a TTL / USB adaptor and run the DEscribe software. However I'm not sure ramping is available in all versions. I'm going to have to look it over.


Not really sure Dave. I'm in way over my head with microcontrollers and motor controllers of any sort. All I really know is it ramped and mixed perfectly and smoothly when I had it connected to 2 channels on my Futaba RC unit. That is PWM though right? But I trhought that was analog? I did experiment with using PWM controls in ARC but there was no simple way to use PWM with a joystick without writing custom script... I think. Don't even know if it would work the same. I would imagine its possible to do.

No idea though... BUT always interested in future improvements;) confused



@Dave, it looks like you are absolutely correct. According to the Describe manual, on the Simplified Serial page, you set the check box next to "Use exponential map in serial mode" and then on the general tab, you can set your ramp time, dead band, and max voltage.

Unclear of you can use the exponential mode mapping in simplified serial (gives finer grain control over the ramping). It appears to need another dip switch setting that may only be available in analog and RC mode)

Here is the link to the doc:



Very nice Gwen. Love the robot and the music. He moves smooth and rotates nicely. Will his arms move like in the TV series, that would be cool. Thanks for sharing and hope to see more videos from Halloween.



That was a MOST Enjoyable video. It did make me a little nervous however. I kept waiting for a car to come along about 50 mph and hit the Robot. Glad that did not happen.


Very good Job Gwen, No kidding the robot as a whole looks like it was a professional prop from a movie.


Yes he looks very professional! Amazing work!


@Aislinn Ok, Here's my video...



Gwen. This is so cool! Nice work. Did you sent this to the EZ Robot holidays contest link also? If not I'm not sure they will find it if it's posted here only. Good luck!


Yes I did Dave. Thanks!

If only I had had the time to isolate and grab his authentic defensive electro ray sound...