Archive for May, 2008

May 6, 2008: 3:23 pm: Errata, jACT-R, Robotics

I am. I am.

Surprise, surprise, my previous rant was completely unjustified. Turns out it was my own stupid fault. I was programmatically launching player, unfortunately I forgot to harvest the program’s stdout and stderr. The process’s buffers were flooded. Stooopid Ediot!

But, at least the monkey sims can run for much longer now. And not a moment too soon as the robot lab is rapidly filling with interns. (It’s such a nice change of pace to no longer be on the bottom of the totem pole)

May 5, 2008: 3:59 pm: Errata, jACT-R, Robotics

I love division of labor, it saves us all from having to reinvent the wheel.. but sometimes it just drives me insane.

I’ve hooked up player/stage through a java client, enabling jACT-R (and the monkey models) to interact in the simulated robotic environment. For sometime now I’ve had a bug where stage would freeze after around four minutes of simulated time. I initially thought it was due to my unorthodox use of the client (the threading model in the client is a tad weak), so I reverted it back to the normal usage and the simulations were now running past four minutes with no problem. Yay, problem fixed!

Nope. Now it dead locks around 6 minutes. So maybe it’s a problem with stage? Lo and behold, someone else was encountering a similar problem. The recommended fix? Upgrade to playerstage 2.1, which is, of course, not support by the client yet and no one has posted any word on an ETA.

I am able to detect when it occurs, which lead me to believe that I’d be able to disconnect the clients and reconnect. Unfortunately, the only way to resurrect stage at this point is to completely kill the socket owning process. My only option is to not only disconnect the clients, but then force quit stage and restart it.. Ick!

I think it’s time to work on something else for a little while.

* This is not meant as a disparagement of anyone’s work, rather just me venting. I fully acknowledge that the same statements could be- (and probably have been-) applied to my own work.