Considering the magnitude of iRobot's (Nasdaq: IRBT) earnings beat Wednesday, you might have expected management to boast. Instead, this longtime Motley Fool Rule Breakers recommendation played it cool.

Reporting after markets closed, iRobot announced that it grew revenue 12% in fiscal Q4 2011, and increased profits at a 30% clip. The quarter wound up a simply monster year, in which iRobot's cumulative revenues leapt 34% and profits exploded upward by 638%. When all was said and done, iRobot earned $0.96 per share.

Once again, iRobot owed the bulk of its success to two factors:

  • International sales of the Roomba (and corollary "home robots" designs). Sales here rose 70% over 2009 levels
  • Warbots. So-called "government & industrial" sales climbed 29%, and recent bullish pronouncements from the Pentagon suggest that we could see further sales of the SUGV robot that iRobot is building for SAIC (NYSE: SAI) and Boeing (NYSE: BA).

But even in the lagging U.S. home robot market, iRobot reversed last year's decline, eking out a small sales gain in the final months of the year. Looking forward, management predicts a somewhat less hit-it-outta-the-park performance in 2011 -- but still a good year overall. Sales are projected to climb 12% or more, while profits (lacking last year's tax boost) should at least hold steady in the mid-$0.90s.

What's under the hood?
As you may recall, three months ago I worried that Roomba inventories had once again begun to outrun sales growth. That was bad news the last time we saw it happen, so last month, I urged you to keep close lookout in case the issue reemerged in February.

To the contrary, iRobot consigned this worry to the dustbin of history. Year-end inventories now show a 16% Roomba reduction from year-ago levels -- quite a feat, considering the strong 34% growth in sales . Accounts receivable, too, are down roughly 3.5% from a year ago. With its cash management now once more beyond reproach, iRobot easily achieved my projection for free cash flow, generating $36.6 million in 2010.

Here's hoping for more of the same as the New Year trundles along.

Fool contributor Rich Smith owns shares of iRobot, a Motley Fool Rule Breakers recommendation. SAIC is a Motley Fool Inside Value selection and a Motley Fool holding. Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.