The Deliverator – Wannabee

So open minded, my thoughts fell out…

Archive for September, 2006

Robots, Robots, Robots!

Posted by Deliverator on 29th September 2006

I haven’t been very active with robotics related activities of late, but am starting to feel ready to engage myself. The TRC is currently at the start of the First Lego League season, which really doesn’t interest me much (although the new NXT kits are far cooler than the previous Mindstorms). The FRC season is still a long way away, although a LOT of work needs to be done in advance of the FRC season to prepare the team to better compete this year.

-For the first time, there is going to be an official Vex competition in the northwest and it will be held in the Seattle area! I am very excited about this, as I view Vex as a much better step towards FRC than FLL. I just hope there is enough interest from the TRC to field a team.

-I would really like to play around with processing data from the CMU cam. Hints given at the end of last year’s International First Championship in Atlanta really pointed towards this being important for teams which wish to compete at a high level.

-There is also much work to be done in designing, building and evaluating a new drive train design. Concerted fundraising efforts in August didn’t yield a lot of extra $ for the TRC, but lead to some good contacts with nearby machine shops. This may the TRC the ability to realize more ambitious designs, but will at the same time require us to become much more proficient with CAD software and getting the math right before construction begins.

-The TRC really needs to either get rid of a whole heap of sometimes useful, but seldom used stuff in the TRC room, or find somewhere else to store it. At present, the TRC room is too cluttered for more than a few people to move about safely, much less use it regularly as a robot design and fabrication room.

-I would really like to see the establishment of an adult run TRC booster organization. Amy, the TRC’s lead mentor, has been against this for reasons that are somewhat nebulous to me. I think it is great to have students running the club, but I also think that adults can be more persuasive at getting other adults to fork out real dough as well as being more disciplined/obsessive about going out and doing something day after day despite discouraging results. There are also a number of hoop that the TRC currently has to jump through in order to do certain types of fundraising, adding to the already considerable organizational overhead of the club. An external booster organization would not have such limitations.

-I am still very keen on the idea of establishing a common place for all area teams to practice/skirmish during the six week period between contest release and the ship deadline. I know club COO Erik Wells-Thulin is very interested in this as well. Not having a permanent field (even a partial one) to practice on is a serious obstacle to effective autonomous programming and driver training and the limited time we get for these activities at the pre-ship skirmish is really inadequate. I wish local schools would do a better job of supporting invaluable activities like robotics with facilities in the same way they support drama, sports and other space hungry activities.

-The club website is in bad need of updating. Ryan was able to throw a plaster on the sucking chest wound that is the current site and get some of the problems related to Cold Fusion under control, but a complete redesign is really in order. Ryan and Paul have been working on this a bit recently and I was pleased by what I saw from the prototypes, but I don’t believe the new site is ready for deployment. Ryan is back to school now and has a very heavy workload, so I doubt he will have much time to devote to finishing it off.

-I would really like to see the TRC participate in more robotics related field trips & activities outside the scope of FIRST. I will be attending Robothon tomorrow and Sunday at the Seattle Center and hope to see some of the TRC membership there waving the flag or just checking things out. I was contemplating attending Toorcon, which is being heavily attended by SWN members, but I have been travelling a lot recently and am feeling quite road-weary. You also can’t beat the price of Robothon…

In short, there are a lot of things the TRC could be doing. I am unsure at this point to which tasks I want to commit my time, sanity and $. I would really like to do Vex stuff, but am unsure of the interest level. I am going to try to start attending meetings again regularly and see if I can gauge people’s interest.

Posted in General, Titan Robotics Club | 1 Comment »

UPX Compressed Minimo

Posted by Deliverator on 27th September 2006

The lead developer of Minimo has released a new build which has been compressed with UPX4PPC. UPX essentially compresses an executeable and turns it into a self extracting, self executing, smaller version of itself. The decompressor is tacked onto the front end of the exe, so no seperately installed software needs to be present on a system to use UPX compressed executables. On systems with limited storage & execution space like a PDA, UPX compressed exes can be a big space saver and will actually decrease time to execute many programs. On my Netbook Pro, it now only takes 12 seconds for Minimo to load to google instead of the 18 seconds that a non-compressed build from around the same date took.

Posted in General | 4 Comments »

Carputer Upgrades

Posted by Deliverator on 20th September 2006

I have been contemplating doing some upgrades to the carputer for some time. I would really like to shrink the carputer’s footprint quite a bit, so that it can be moved completely out of sight (including cable runs) under the passenger seat or into the bulkhead space taken up by the stereo system. To accomplish this, I would have to shift to an even smaller components, such as a Via Nano-ITX motherboard, smaller powersupply, etc. I would particularly like to stop using shock damage prone hard drives for storage. Samsung has been shipping 32 GB solid state disks to OEM’s (noteably Sony, for use in their non-umpc umpc) for a while and TDK has been sampling their own solid state disks as well. It is only a matter of time until these trickle down into the consumer space. I would also like to replace my current touchscreen with a transflective model. Mp3car.com, from whom I have purchased a number of carputer components in the past (with great satisfaction at their responsive service), is selling a transflective kit for a reasonable chunk of flesh. I would also like to get a display with a more standard native resolution. I have seen a number of 8″ displays (only slightly larger than my current 7″ Lilliput) with 800*600 native resolution. My current display has a very non-standard native resolution of something like 808*480, which is not supported by the onboard video on my motherboard and makes for rather blurry fonts. Last, but not least, I would like to upgrade to iGuidance 3.0, which now has a version specifically for 7″ display equiped carputers and UMPCs. I have to mull things over a bit more, but will probably be making some preliminary purchases in the next few days.

Posted in CarPuter, General, Tech Stuff | No Comments »

Coolmax PS-224 Power Supply Tester with LCD

Posted by Deliverator on 14th September 2006

Coolmax PS-224 Power Supply Tester

As you might have gathered if you read my previous entry, I recently purchased a standalone power supply tester, a Coolmax PS-224. Most power supply testers simply have a series of LEDs that light up if a given line is outside a narrowly defined “good” voltage range. Better testers will have multiple LEDs for each voltage line to indicate whether a line is reading high or low and whether it is off by a little or a lot. Coolmax’s tester takes the cake, though, by essentially integrating a backlit digital multimeter into the tester and displaying the exact voltages found, as well as having the usual alarm tones and idiot lights. The PS-224 is capable of testing 20 and 24 pin ATX power supplies, as well as 4, 6 and 8 pin auxilary connectors, Molex, SATA and 4 pin floppy connectors. The built in metering checked very closely to a good standalone multimeter when using a dongle to power the supply up. I don’t believe the PS-224 places a significant load on the supply, so you have to take the results with a grain of salt, as you don’t have the same voltage sag that can occur under significant loading, but it is an excellent tool to assist in diagnosing hardware problems and is far superior to any other power supply tester I have encountered. The PS-224 is available for about $25. I purchased mine from Xoxide, from whom I have purchased several other items in the past without complaint.

Posted in General, Portable Computing/Gadgets, Rants and Raves, Tech Stuff | No Comments »

Panasonic HD Powerline Adapters

Posted by Deliverator on 14th September 2006

I have not been entirely happy with the reliability of my wireless link to my media center box off the kitchen. My house has aluminum siding and combined with some persistent noise sources does not make for the best WiFi environment. I decided to try out some of the new high speed power-line networking gear that has recently come onto the market.

I have been pretty pleased with the reliability and consistency of Netgear’s powerline to ethernet bridges (the ones that look like little silver wall warts), which I have used on a number of occasions in WiFi challenging scenarios. The major sticking point with these devices has been their speed. While most offer speeds faster than a typical DSL line, they don’t come close to rivaling the speed that can be achieved with wired ethernet or even 802.11g wireless gear. Where power-line gear has shined is its simplicity and consistency of use. In my experience, so long as you plug them directly into a wall outlet (and not into a power strip or UPS) they just work. For most people’s uses, these devices offer a quick and dirty way to get a computer or other device only with a minimum of fuss. In my situation, though, I needed a solution capable of streaming bandwidth video from my file server to my media center. Several manufacturers have released a new generation of power-line networking gear, often including the “HD” moniker in the product name.

I took a trip to Frys and was disappointed to see that they only had a single Netgear HD adapter on the shelves. They did however have copious quantities of Panasonic branded HD power-line adapters, sold as a two adapter kit (model BLPA100KTA) for almost $50 cheaper than a pair of the Netgear HD adapters. I purchased the Panasonic Kit and took it home. Here is where the frustration begins.

I unwrapped the Panasonic adapters and read the included documentation. The kit adapters come pre-paired with encryption. If you purchase additional adapters beyond the two in the kit, you have to press a button on the “master” adapter and the new adapter within about 3 seconds to add the new adapter to the network. I plugged my two adapters into the same outlet and the PLC lights on both units lit up indicating a connection. I plugged the units directly into the wall outlet in different rooms and began to have problems. In some cases I could get a connection and in others I couldn’t. I went back to the manual and read up on their long list of potential interference sources. In some cases unplugging a cell phone charger on the same breaker circuit was enough to establish a connection. In other cases, unplugging every other device on a particular breaker wasn’t enough to get a connection established, even with both adapters on the same physical circuit separated by no more than 50-100 wire feet. Needless to say, I was unimpressed.

I tried the adapter upstairs next to my media center and was thankful when I got the PLC lights to light up…for about 30 seconds. If I plugged the adapter in again, I could get it to light up once again, but only for a short period of time. I looked at what else was on the two breakers and unplugged everything I possibly could live without, short of the two computers themselves. I managed to get the PLC lights to stay solid. I then ran a short ethernet cable (not included in the packaging, unlike EVERY other power line adapter I have used) from a switch next to my media center into the Panasonic adapter. When I plugged the cable in, the PLC light immediately went off. I tried different cables and met with the same result. If I disconnected the ethernet cable, the PLC light would come back on. I tried plugging the ethernet cable directly into my media center and the PLC light went off. About a minute later, while I was trying to decide on what to try next, my media center shut off suddenly and would not come back on. I disassembled the media center and tested the power supply with my nifty new Coolmax LCD power supply tester, which revealed no signs of life from the power supply. On closer examination, I found that one of the capacitors had “bloomed.” I connected up a very good desktop supply and my media center powered right up. So, at the moment my mini-media center is powered by a power supply almost as big as itself. After five hours of troubleshooting and repair of my media center, I was pretty pissed off. I returned the adapters to Frys. Supposedly the Netgear HD adapters are designed around a different standard, and my past positive experiences with their previous generation of power-line products makes me more inclined to trust them not to kill my gear.

Posted in General, Rants and Raves, Tech Stuff | 1 Comment »

10w flashlight with Lumileds K2 LED

Posted by Deliverator on 7th September 2006

I recently added another LED flashlight to my growing collection, a “10w” model sold by Fifth Unit. Fifth Unit operates very similarly to the now defunct AXShop (namely, obscenely low prices and long ship times), carrying much the same type of wares and is rumored to have some of the same employees. This new flashlight is much the same as the “7w Golston” I also own, with a virtually identical casing and a slightly different, recessed, two brightness mode end cap. The main difference is the use of the new Luxeon K2 emitter. These new emitters put out more light, can have higher driving currents and tolerate higher operating temperatures than previous Luxeon LEDs, which were still industry leaders in brightness. In reality, despite the 10w vs 7w designator in the name, this new flashlight is only nominally brighter than my 7w and actually has a slightly weaker “throw.” The real reason I was interested in this new flashlight is that it is capable of using the higher voltage lithium ion CR123 rechargeables.

There are basically two versions of a Lithium-ION CR123 rechargeable. One is designed as a drop in replacement for disposeable 3v Lithium batteries. A good deal of the interior space of these 3v Lithium-ION is devoted to regulation circuitry and devices to keep the cell from exploding or doing other nasty things due to deep discharge, overcharging, overheating, etc. As such, these cells have a much lower amp-hour rating than a disposeable cell. Even with the lower amp-hour rating, these rechargeable cells are often not very useful in flashlights without a voltage regulator circuit. When loaded, the voltage output by these cells quickly drops below a useful level and the LED flashlight quickly dims. So, even though these cells still have a lot of juice in them, they don’t produce enough forward voltage to get the LED to light up very brightly. When I use 3v rechargeables in my 7w Golston flashlight, I get maybe 15 minutes of bright light out of it, if I use it only intermittently. If I leave the flashlight on continuously, I get even less useful life out of the batteries. Thankfully, there is a solution. There is another type of lithium ion rechargeable CR123 cell available. These don’t waste a lot of space to regulation and as such have a higher amp-hour rating. These cells also have a much higher voltage, usually about 3.6-3.7 volts loaded. Hot off the charger, these batteries will be as high as ~4.2, which is high enough that you can burn out some devices designed for 3v disposeable CR123s. 4.2 volt cells are too much for my 7w Golston with its already overdriven emitter, but these cells work quite well in my new K2 based flashlight. In addition to the greater AH capacity, these cells stay above the needed forward voltage bias needed to drive the emitter at peak brightness for a much longer time.

This summer, I have taken to walking around the hill late at night listening to Podcasts. With my 7w Golston flashlight running off 3v rechargeables, I had to use my flashlight intermittently or risk running out of juice before finishing my walk. With my K2 flashlight running on 3.7v rechargeables, I can leave my flashlight on for the whole hour without worry. There is great peace of mind in not having to worry about quickly turning on your flashlight just so that the drunken guy in the beat up pickup truck (who hasn’t yet quite figured out the headlight switch) doesn’t run you over.

Posted in General, Portable Computing/Gadgets, Tech Stuff | 1 Comment »

Adesso WKB-4000US

Posted by Deliverator on 7th September 2006

I purchased a new RF wireless keyboard for use with my media center PC, an Adesso model WKB-4000US. I was a bit dissatisfied after long term use with my previous RF wireless keyboard, a BTC model mentioned in a previous post. I found the BTC’s handles, which made it soo easy to grasp off the coffee table also made it barely fit on the coffee table. The receiver unit would also periodically hang, requiring a USB replug and reassociate to get it back up and running. I also found the “joystick” mouse a bit cumbersome for rapid fire couch browsing.

Adesso WKB-4000US

The new Adesso keyboard is much lighter than the BTC and takes up a much smaller footprint on the table. It is easy to pick up thanks to the generously sized integral wrist rest. In the center of the wrist rest resides a generously sized touchpad with left and right mouse buttons and a “touch to scroll” area built into the touchpad. The keys themselves are wonderfully rigid, with no side to side slop and a satisfyingly clicky response that is all too rare in these later days of computing. The receiver unit is a simple little USB dongle. The unit operates in the 2.4ghz range, but I have noticed no interference with my WiFi networks and the range on the keyboard is excellent. I have had no issues with it since initial pairing.

Really, my only gripes with this keyboard are very minor:

– The pairing button on the USB dongle is rather small, requiring a mechanical pencil or similar tool to press.
– The scrolling area is easy to accidentally move into while exhuberantly cursoring about
– $90 pricetag is over twice the cost of the BTC keyboard, although this is still much cheaper than the overpriced Gyration RF keyboards, which have a rather poor build quality in my experience and tend to have keys come loose. The Adesso feels very solidly put together.
– No media buttons on keyboard might be an issue for some people

Posted in General, Portable Computing/Gadgets, Rants and Raves, Tech Stuff | 1 Comment »