"affirmative. K-9 2.0, Online And Fully Operational." (well, Almost Fully)


@Steve... Sweet.... more and more ez robot projects are getting noticed... Smile


I may have missed it in the instructable, but you mentioned adding mountain bike tires to the wheels. I assume you cut them to fit. How did you adhere the tread to the wheels?

Also, what is the total weight of K-9, and how fast does he move with those motors/wheels?

I have a set of power wheels motors and gear boxes (but no wheels) and a set of wheelchair motors with wheels, but missing bolts that hold the wheels together that I would need to source. Haven't decided yet which to use, but getting wheels for the power wheels and running the system on 12 volts instead of 24 is starting to have some appeal.



@Steve... Wow! That is a very thorough and cool Instructable. Now I want to build a K9 more than ever! Thanks for taking the time to this. This is extremely helpful to robot builders everywhere. Good job!



Thanks buddy. Yeah, the number of EZ Robots are certainly growing in the public domain. "An EZ Robot in every household", You know what, DJ and his team just might pull it off. Winky


Do you know what, I proof read that twice and never noticed it, I forgot to add the tyre bit in, opps *sleep* (it's in there now). Anyway, Yes I did cut the tyre down to length and trimmed off the tyre walls. I was going to use adhesive but decided against it and went with simple evenly spaced nuts and bolts. The head of the bolts sit on the base of the tyres in-between the treads so they don't touch the ground and the tyres can be easily replaced if needed. K-9 weighs about (rough guess) 30 to 35KG, and with PWM set to 100 he can get to about 6 MPH/9.5 km, but I have most of his PWM scripts set to 50, so about 2.5 to 3 MPH/ 4.8km. Even at top speed the traction is excellent. Using 12v either on a lead acid or LiPo battery powers the motors great with power in reserve.

Hope that helps, (and thanks for the heads up). Here's some pics for you. Smile

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Thanks for you kind words and pleased you liked the Instructable. I hope it gave you some ideas. Come on my friend, get building. K-9 needs an overseas relative, and I would love to see your approch at building one. Grin


Thanks for the wheel information. If I can score some wheels for my Power Wheels motors/gearboxes I may go that route. I like the compactness of your drive train (although I think I will use differential steering and have a couple of casters trailing as rear wheels instead of a steering servo). My wheel chair motors are 15kg on their own, and take up a huge amount of space, and provide much more power and speed than I need. I think I will save them for another project like a Segway clone.

I was thinking about adding foot pegs and a T-bar handlebar so I could ride the robot while standing, which would require the wheelchair motors, but that was more so that I could claim it was an assistive device and bypass the luggage weight limit if I travel by train. Using the smaller motors, I can keep the overall weight low enough that it isn't an issue.

Great instructable. There are things that I would do differently like replacing the servo activated switches with TIP120 circuits or relays, but more important that you made it work, then that it was done in the most elegant fashion. I am certainly going to take design cues from how you did the neck/head and some ideas from the body build as well.





Pleased you liked the Instructable. I have to agree with you about the diff steering. It is an easier set up, control and build wise, but I went for the independent steering simply because of the size of the doorways and halls in my house. Having the diff steering would have caused massive overswings from his head and rear when turning in to rooms, thus causing lots of bumps and scrapes (mainly to the walls).

This was my first full robot build and wasn't aware of things like TIP circuits, but thanks to you guys that's something I am looking in to on future projects (I hope Rich hasn't forgot about me), as well as other things I've picked up along the way. Can't wait to see what you come up with Alan. Smile


UPDATE 2.0/5

Oh no. Who killed the dog?

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Well he's not quite dead, but certainly lifeless when this picture was taken.

So a bit of a major update to share with you guys as K-9 has had a bit of a face lift, or rather a transplant for want of a better description. So I've been a community member for almost a year now and I'm constantly looking through the forum checking out what you guys are up to and how your robot projects are progressing. While doing so, one thing sticks out for me in regards to some of your builds. Wiring. As much as I love tinkering with electronics, there's one thing that always bugs me, which is messy wiring, and K-9 was unfortunately no exception.

After looking at the robots made with the likes of Richard R's and Bob Huston's InMoov's (there must be a ton of wiring in there), as well as Steve S, Mcsdaver, Dave S, and many more of you guys, one thing I noticed is how tidy you guys keep your wiring. And after seeing Tony the ToyMakers really neat work on his Altair EZ:2 build, that was the last straw (in a good way, as it was the kick up the butt I needed), and figured I could improve on what I had done. So I initially set about tidying up all of K-9's wiring (a day or two's work), but ended up ripping out his entire electrical system and started again from scratch (which took a little over 2 weeks instead).

So from a simple re-wiring job to a full out electrical rebuild, K-9's internal's have gone from this...

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to this...

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Yeah it was a lot of extra work, took a lot longer than expected, and cost me a few more beer tokens, but it was worth it now he looks a little tidier than he did.

I was also glad I did this for another reason. It gave me the chance to make a few changes and improvements, a couple of repairs, and the chance to add a few more sensors (so I won't have to make further repairs, hopefully). In the next post (post #52), I'll go through what the new changes are with a few more pictures for you guys to check out. Smile

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Wow, fantastic job Steve! This now looks like something a Timelord really would build.




Lol, thanks Tony. Hopefully I've made the good Doctor proud Tongue.

As well as thanks for the kind words, I'm also grateful you posted your Ez-b V4 Gear-tray thread. If it wasn't for that, I probably wouldn't have done the re-build for quite some time, so you gave me the motivation I needed. Smile


Steve, glad the gear-tray idea worked for you. Case in point, I have just needed to get the gear-tray out of the EZ:1 for modifications and it takes less than 15 minutes to completely extract it, and about the same for re-installing it. I meticulously mark/name all cables so it is easy to find where they belong.

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