impala
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Location: Queensland. Australia.

Robot

Tue Apr 09, 2013 2:15 am

I have at last just finished building Simon Monk's Robot and find the software procedure for the autostart does not work.Also the Robot goes pretty fast and nearly out of control as difficulty in steering.The stop button being used quite a lot!!! Grateful for any suggestions as SM is a hard person to contact.

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joan
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Re: Robot

Tue Apr 09, 2013 8:19 am

Some links would be useful for those of us who are ignorant of Simon Monk's robot.

simplesi
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Re: Robot

Tue Apr 09, 2013 8:53 am

Do you mean a Magician Chassis with his RaspPiBotBoard on it :)
https://www.sparkfun.com/products/11561

If so, he was showing it off last night at our Preston RaspberryJam and it will go slowly as well as fast so don't panic just yet :)

He's normally quite contactable via twitter using @simonmonk2

regards
Simon
Seeking help with Scratch and I/O stuff for Primary age children
http://cymplecy.wordpress.com/ @cymplecy on twitter

mikerr
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Re: Robot

Tue Apr 09, 2013 9:32 am

Simon Monk is the author of the book: Programming Raspberry Pi: Getting Started with Python
http://www.simonmonk.org/?page_id=63

A chapter or two is dedicated to a robot which is based on the magician robot chassis:


Image
https://www.sparkfun.com/products/10825 [US] or http://proto-pic.co.uk/magician-chassis/ [UK]

and the controller board raspirobot:
https://www.sparkfun.com/products/11561
Android app - Raspi Card Imager - download and image SD cards - No PC required !

impala
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Location: Queensland. Australia.

Re: Robot

Thu Apr 11, 2013 6:07 am

simplesi wrote:Do you mean a Magician Chassis with his RaspPiBotBoard on it :)
https://www.sparkfun.com/products/11561

If so, he was showing it off last night at our Preston RaspberryJam and it will go slowly as well as fast so don't panic just yet :)

He's normally quite contactable via twitter using @simonmonk2

regards
Simon
I would certainly like to know how he did it please!!

impala
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Location: Queensland. Australia.

Re: Robot

Thu Apr 11, 2013 6:14 am

mikerr wrote:Simon Monk is the author of the book: Programming Raspberry Pi: Getting Started with Python
http://www.simonmonk.org/?page_id=63

A chapter or two is dedicated to a robot which is based on the magician robot chassis:


Image
https://www.sparkfun.com/products/10825 [US] or http://proto-pic.co.uk/magician-chassis/ [UK]

and the controller board raspirobot:
https://www.sparkfun.com/products/11561
I have built the Robot kit from Sparkfun and also have Simon Monk's book from which it was built and find that the updated software procedure is different from the book and advice is sought.

impala
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Location: Queensland. Australia.

Re: Robot

Thu Apr 11, 2013 6:21 am

I would like to know how Simon Monk made the Robot go slower!
Also I built the Robot from a kit from Sparkfun and also have Simon Monk's book . The software was varied and I am seeking advice on it as the procedure as stated in his book does not work for me.

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rurwin
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Re: Robot

Thu Apr 11, 2013 6:50 am

I have not read the book nor built the robot, but in general I would trust the website more than the book, since the book can only describe things as they were several months ago, and the raspibot website is maintained by Simon Monk.

I would take issue with the first instruction for installing software though, (Tutorial 01 Getting Started) because, if I understand correctly, RPI.GPIO is already installed in Raspbian.

Si.
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Re: Robot

Thu Apr 11, 2013 7:56 am

Hi,

Yes, as always, the Internet moves faster than publishing!

The latest construction instructions, software setup instructions, tutorials, videos and the library itself can all be found on the Github Wiki that accompanies the Python library. Following http://www.raspirobot.com will now take you straight to the Wiki.

BTW: SKPang also sell the RaspiRobotBoard in the UK.
--
Simon Monk

mikerr
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Re: Robot

Thu Apr 11, 2013 10:48 am

impala wrote:I would like to know how Simon Monk made the Robot go slower!
Just quickly pulse the motors on off (PWM) to vary speed, or use less voltage (are you using 4 or 6 AAs ?)

Not read the book though I do actually have a magician chassis & motors with an arduino.
Android app - Raspi Card Imager - download and image SD cards - No PC required !

Si.
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Re: Robot

Thu Apr 11, 2013 10:11 pm

The example code is just on / off for the motors at the moment. Although its not so hard to add PWM. I am using 6 x AA (NiMh). The motors are supplied from the unregulated side (direct from batteries). The LDO regulator powers the Pi.

impala
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Location: Queensland. Australia.

Re: Robot

Fri Apr 12, 2013 4:32 am

I am using 6 NiMh AA batteries. Would appreciate how to add PWM as only a beginner in all of this.Also have been to the new web site at Github.Still unable to get autostart to operate.

Si.
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Re: Robot

Fri Apr 12, 2013 6:34 am

The autostart mechanism I describe in the book only works if you have your Pi set to automatically boot on to the desktop.

For an alternative, take a look at this dependency method - http://learn.adafruit.com/drive-a-16x2- ... nit-script

At some point, I will update the library for PWM, I believe RPi.GPIO has now been updated to use PWM.

Si.

mikerr
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Re: Robot

Fri Apr 12, 2013 9:17 am

You could do simple PWM yourself:

e.g. half speed for 2 seconds

Code: Select all

for num in range(1,10):
	motor on
	time.sleep(0.1 )
	motor off
	time.sleep(0.1)
On for a 1/10th second, off for 1/10th ... so its spending half its total time on, therefore half speed.
Android app - Raspi Card Imager - download and image SD cards - No PC required !

impala
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Joined: Sun Feb 17, 2013 1:36 am
Location: Queensland. Australia.

Re: Robot

Sat Apr 13, 2013 2:06 am

Many thanks Si and Mike for your comments and will have a look at these shortly as will be away for a week -10 days
John

impala
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Location: Queensland. Australia.

Re: Robot

Sun Jun 09, 2013 3:12 am

I returned a few weeks ago and have had several friends look at this situation too. As the latest program on the Git hub seems to be quite different from that in the book perhaps someone would be kind enough to give me step by step procedure from after the program has been downloaded from the Git hub We are now thoroughly confused and would appreciate any help please. :( :?

ghans
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Re: Robot

Sun Jun 09, 2013 9:42 am

Where do the instructions linked by rurwin fail ?
Post error messages.

ghans
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