Comments on: Updates / Errata

By: file.circular

file.circular — Mon, 09 Feb 2009 17:47:17 +0000

Hi,

On page 95 in Hacking Roomba

The “r” term in the equations

r = b(Vleft+Vright)/(2(Vright-Vleft))

Vleft = V(1-b/2r)

Vright = V(1+b/2r)

is the distance from the origin to the center of the wheelbase.

This “r” term is not the same as the one in the preceding diagram which is the distance from the origin to the center point of the left wheel.

It may be helpful to redraw the diagram such that “r” is the distance from the origin to the center of the wheelbase.

This will yield the following equations for Vleft and Vright:

Vleft = (r-b/2)Ө

Vright = (r+b/2)Ө

By: todbot

todbot — Tue, 04 Dec 2007 18:49:20 +0000

Short answer: Yes, it’s compatible with Vista.
Longer answer: The software is all written in Java, so as long as there’s a Java VM available for whichever OS you’re on, the code should work. Some OSs come with Java, if yours doesn’t, you can download it from Sun:
http://java.com/en/download/manual.jsp

By: Matt

Matt — Tue, 04 Dec 2007 14:38:19 +0000

Is the software for hacking roomba compatible with Vista?

By: Argyrios

Argyrios — Fri, 24 Aug 2007 17:20:46 +0000

Hi again,

Just a little misprint:
on page 30, line 6, it says that “When going forward, a positive radius turns Roomba to the right, and a vegative radius turns Roomba to the left”.
Actually, it is the other way around:
“positive velocity and a positive radius will make
Roomba drive forward while turning toward the left”

PS. The book is simply great and, without it, it would take me years to start programming Roomba!

By: todbot

todbot — Wed, 22 Aug 2007 17:24:46 +0000

Hi Argyrios,
I do actually mean velocity. In this context, theta is essentially rotational velocity (aka frequency, units 1/sec) and when multiplied by a radius, gives a radial motion velocity (units distance/second) around a circle of that radius.
I didn’t go into that detail in the book because the editor already thought it was a little math-heavy. :)

By: Argyrios

Argyrios — Wed, 22 Aug 2007 14:02:49 +0000

Hi,

I am reading page 95, where it says that the velocity of the left wheel if

Vleft = r * theta

r = radius and theta = angle

I think what was meant here is ‘arc length’ instead of velocity

regards,
Argyrios

By: Argyrios

Argyrios — Tue, 13 Mar 2007 01:41:34 +0000

Hi!

I am working on a project that involves Roomba, so besides interesting, this book is a life-saver for me. Good work.

I will note any typos that I find along the way and send them. One I just found, is at page 39, where the code implements a 45 degree right turn, while the text talks about a 90 degree turn.

best regards,
Argyrios

By: todbot

todbot — Sat, 27 Jan 2007 18:38:01 +0000

Hi thanks for getting the book!
Both domains work. All the links to downloadable code point to roombahacking.com, while this site is at hackingroomba.com. I did this in case Wiley (the publisher) wanted to do something with the “Hacking Roomba” domain, since they own the title. It’s a little confusing I know, but hopefully not too much.

By: Hans-Jürgen Sasse

Hans-Jürgen Sasse — Sat, 27 Jan 2007 18:19:05 +0000

Hy, a great book, thank you
I have found a minor error

on first page of chapter 16, your webadress is wrong
wrong http://roombahacking.com
correct http://hackingroomba.com

By: todbot

todbot — Fri, 08 Dec 2006 23:21:55 +0000

Hi Vic, the book just came out. Officially released on 20 November 2006. Of course it was finished in August and three months in the ever-changing world of technology means some tools used in the book will be improved. The techniques presented and the Roomba protocol will be valid for several years however.