Minutes from the February 2005
Connecticut Robotics Society Meeting:
Total attendance: 14
The meeting commenced with a viewing of Innovations, a PBS show on cutting-edge bionics.
After this, Jake did the usual introductions.
A new member showed the group the platform he intends to use in the Trinity Fire-Fighting Robot Contest. He told us that he wants to use an OOPIC-C (programming it in Visual Basic), a unique CdS detector, and Sharp IR detectors for sensors. He intends to compete in the Junior Division.
Jake next told us about the RoboTrends gathering to be held in Boston in the month of May. We get one free ticket for putting a link to their website on ctrobots.org.
Jake next told the group that a Grandar (Chinese robot maker) VP might make a visit to the March meeting if she is still in town.
Ed told the group of his idea of loading a 200 byte program into the RAM of an HC11 to enable the HC11 to tether to a PC to read sensors and provide debugging information.
Jake next held a “raffle” for two Chinese tee-shirts.
Our featured speaker was up next. Mark W. gave a great talk on programming PLCs. Mark told us that PLCs were invented by Dick Morely(sp?) to replace sequential relay circuits. Basically a PLC reads an input signal, processes it and writes an output signal. Put another way, the PLC looks at inputs and depending on the condition of the input, turns outputs on and off. PLCs come in modules (cost between $49 - $200). You can get a complete PLC for as low as $100. PLC I/O can be daisy-chained. There are two ways to program a PLC - 1) use a PC and s/w (ladder logic) or 2) use a hand-held keypad via RS-232. As for the pros and cons – pros first. PLCs are more rugged than a PC. And PLCs are good for turning outputs on/off depending on inputs. For the cons. PLCs sport no advanced math and they are bad for interfacing to databases. Thanks Mark for a great talk!!
The meeting adjourned around 3:15pm