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My new robot friend


#1

It has been a lot of work and a lot of research hours and tinkering…
I am happy to announce that my rosvem project (v2) is now alive.

Thanks to all the guys who helped out picking motor controllers and helping with general questions, I now have a new robot friend!

Of course it’s only driving around at this point, still a lot to do… :stuck_out_tongue:

A special thanks to all who helped and made this possible so far!

My blog post:
http://robertjacobs.eu/2011/02/11/rosvem-is-alive/

And if you just want to see the video:

Oh yeah, don’t forget to add me on twitter:
http://www.twitter.com/foekie
Thanks 8)


#2

Looks really good! Have fun!


#3

Sweet…even goes on steps, nice one.


#4

Very good work :clap: Should I say : “as usual” ?


#5

So, what are you going to do next with the Rosvem? Any plans to do live video?


#6

Thanks for your nice response!

[quote]So, what are you going to do next with the Rosvem? Any plans to do live video?
[/quote]

Yup. The software is already ready for live video. It’s now working with the webcam of my laptop, but using composite video via usb works perfectly too. Only thing left to do is buying a camera (suggestions?)

You can check it out here:
http://robertjacobs.eu/2011/01/31/rosvem-chassis-done-video/

You can also see that there is, at this point, random sensor data coming back from the robot. Which is displayed as an overlay on top of the video in the software.

Next step (which I will start with now) is to hook the electronics to a perf board and start soldering :smiley:

The voltage dividers are working perfectly (http://robertjacobs.eu/2011/02/03/voltage-dividing-reading-battery-voltage/) for both the battery voltage and the amperage sensors.

Lots of work to do 8)


#7

Good stuff man. Thanks. Instead of a perf board. Do a pcb and post it on batchpcb. fezzers can buy it.


#8

Wonderful! Your video has inspired me to devote more time back to my little bot. I’ve been having issues with the structure and drive mechanisms.

  1. How are you planning on transmitting the video? Thru the FEZ? With the XBee?

  2. Are you going to put any “intelligence” into Rosevm or will it be 100% user remotely controlled?


#9

The perf board is ready. If I can arrange it, I will upload a picture today.

Via a wireless camera system. The receiver signal will be transferred through usb to my laptop.

Intelligence, yes. Mostly sensors and gps. Not sure what excactly at this point.

[quote]Wonderful! Your video has inspired me to devote more time back to my little bot. I’ve been having issues with the structure and drive mechanisms.
[/quote]

What’s the problem? Can I help?


#10

http://robertjacobs.eu/2011/02/17/drive-electronics-on-a-perfboard-rosvem/

Need to drill some mounting holes later on.
And I need to add another print connector for powering the two amperage sensors. The motor controllers only provide 3.8V instead of 5…

And, I need to add another voltage divider. Maybe even a small voltage regulator circuit.


#11

Thanks.

The hex shaft from the Tamiya gearbox slips in the Tamiya drive wheels. If there’s any resistance, then the bot stops going, despite my motors and gearbox spinning.

I bought some Pololu aluminum disks that have a set screw to lock it on to the hex shaft, but I need to find screws that fit to attach these to the wheels.

(Looks like the same setup with ROSVEM Mark 1)

Seeing your bot, has gotten me to think a bit differently about how to construct mine. I may scrap the system I have altogether and start over again.

Which is ok … since the mechanical stuff was bought cheaply so that I could focus on the FEZ part. I feel somewhat confident with that, now I can move on to a different part of the challenge.

I like your use of cordless drill motors and batteries!!

Would the DC Motor Controller board sold by TinyCLR work with those motors?


BTW - I just subscribed to your RSS feed! Looking forward to some updates :slight_smile:


#12

[quote]The hex shaft from the Tamiya gearbox slips in the Tamiya drive wheels. If there’s any resistance, then the bot stops going, despite my motors and gearbox spinning.

I bought some Pololu aluminum disks that have a set screw to lock it on to the hex shaft, but I need to find screws that fit to attach these to the wheels.

(Looks like the same setup with ROSVEM Mark 1)[/quote]

I did not have any of these problems with v1. The gear boxes were pretty stable, even when driving on carpet.

I like your use of cordless drill motors and batteries!!

Not that will not work. The motors are way too powerful for those motor drivers. The ones I use can power up to 20a each.

A cordless drill motor will ask around 8,5-10 amps when there is no torque.

Thanks for subscribing!


#13

“I bought some Pololu aluminum disks that have a set screw to lock it on to the hex shaft, but I need to find screws that fit to attach these to the wheels.”

Hah. Funny, I did the same thing and forgot to order these 4-40s:
http://www.pololu.com/catalog/product/1962

Not sure you can get these exactly at HomeDepot, but maybe your local hardware. Mcmaster-carr would have, but you probably need more stuff at pololu anyway - right? :slight_smile:

I wish the stepper shafts they sell where keyed. That tiny set screw will head strip and not hold very well under load over time unless you have flat spot on the shaft or it is keyed.


#14

Me too … except I, not knowing what to look for, got the 2-56 version.

I realized they are inexpensive to order, but I don’t want to pay shipping on about a $2 purchase :smiley:

The local Ace had 4-40s, but no 2-56. There’s a specialty place in town that I’ll try next.