Friday, December 19, 2014

New Acumen Release (2014/12/1)

A new release of Acumen (2014/12/1) is now available.  This release features several enhancements, including switching to software rendering of 3D graphics, which makes the distributed executable fully functional on any computer that has Java installed. The latest semantics has more strict error checking, catching more inconsistencies your specification. Experimental support for matrix operations has also been included.

The following video showcases an example that comes with this distribution:

An updated user reference guide is available through the Help menu.  The examples have also been reorganized for easier access.  Essentially the same distribution was used successfully in the most recent edition of the Cyber-Physical Systems course taught at Halmstad University.

Monday, June 10, 2013

Finding Zeno

Remember the story about Zeno's paradox, with Achilles and the tortoise?  Well, now we know how to do a computer simulation of that story :-)

Last week our first paper on enclosures and hybrid systems (entitled, "Enclosing the Behavior of a Hybrid System up to and Beyond a Zeno Point") was accepted for publication at the First IEEE Conference of Cyber-Physical Systems, Networks, and Applications (CPSNA 2013).

The figure on the right, taken from the paper, illustrates the basic idea of the new method on another example of Zeno behavior, namely, a bouncing ball.  The approach presented in the paper is to compute an "enclosure" (illustrated in grey in the diagram).  Using enclosures makes it possible simulate the system past the Zeno point without going into an infinite loop.

Saturday, May 11, 2013

Two Special Guests Visit the NAO Halmstad Group

Two guests who are getting ready to graduate from Kindergarten visited Halmstad University last Friday to meet Jonson and Mörner, two members of the NAO Halmstad Group.  The visit was hosted by Jonas Jonson (no relation), Alexey Taktarov, Yingfu Zeng, Jawad Masood, and Walid Taha.  (See more pictures from visit)

The special guests became interested in meeting the robots after seeing a segment on TV4 about the NAO Halmstad Group.  The visit included showing off some of the capabilities that the NAOs come pre-programmed with (including dancing, Tai Chi, walking, speech synthesis, and speech recognition) and an interactive discussion of how the robots can be programmed by a sequence of basic primitives such as walking, turning, moving hands, closing the grip, and so on.  This was followed by a discussion of what these robots are made of, including cameras, motors, and (as one of our young guests pointed out) microphones.  They were also showed a recording of a recent walk by Jonson using code that was developed by our colleagues at the AMBER lab at Texas A&M.

The guests appeared content with the demonstrations.  Depending on the level of their future interest in this subject, we may have had seven or eight generations of engineers at this meeting.  We will keep our fingers crossed for the next twelve years :-)