|
|
 In the summer of 1999, we had used the bottom two layers of 3T to provide autonomous control for a single subsystem--a second-generation biological water processor--during a 450-day, 24-hour-a-day, 7-day-a week test. Then in January 2000, the Advanced Water Research Group received ALS funding for the year-long IWRS test, involving four advanced water-recovery subsystems (Bonasso 2001) (see Advanced Water Recovery System sidebar).BuildupUsing 3T allowed us to develop the control for the IWRS in a modular fashion in two ways. First, moving from bottom to top (figure 4), each layer has its own data structures, timing constraints, and development tools that allow for parallel development of the software. Thus, we were able to develop skills sets based on the evolving hardware specifications and simultaneously develop the sequencer procedures. Early on, as the water research team developed the design for each subsystem, one part of the 3T team wrote the sequencer procedures for each subsystem in the RAPS language (which, in turn, is written in Lisp) (1) using virtual skills, that is, Lisp skills connected to a Lisp simulation of the expected hardware. A virtual simulation of, say, the reverse-osmosis subsystem could then be shown on a laptop to the WRS engineers and the control design refined in an iterative process even before the actual hardware was available. The primary result of this process was a set of skill specifications for each subsystem (figure 5). long, are stored at rear of bucket when not in use. The TLB-535 heavy-duty compact tractor loader backhoe offers a used3.5hpelectricchainsawmotor 6000-pound digging force that enables the machine to achieve an 11-foot depth. Its dual-cylinder, 180-degree hydraulic cushioned swing suits the backhoe to precise work in tight quarters. An added safety feature is an exclusive heavy-duty boom lock that can be engaged or disengaged from the operator''s seat. The transmission, which is equipped with used3.5hpelectricchainsawmotor servo-control, adds control capability as well as reduced pedal effort in forward or reverse. A load-sensing steering system ensures hydraulic flow only when the wheel is turned. used3.5hpelectricchainsawmotor Terramite''s T7 compact tractor loader backhoe now comes standard with a 26-hp. Kubota or 20.3-hp. Caterpillar diesel engine. This model has extended-reach arms for a 96-inch dump height and a high-capacity front loader bucket with dual front curl cylinders for faster cycle time. Front and rear work lights and center-mount steering are standard features. The T7 is equipped with Super Terra Grip front and rear tires for better traction and maneuverability. It also has a 180 degree swing on the backhoe. T5C features quick-change backhoe buckets in 8- to 38-in. sizes with 1/2-in. thick carbon cutting edges and cast steel replacement teeth. Digs to 8 ft., 4 in. Operating the augerWhen you turn the throttle of the auger, you''ll feel a substantial clockwise force through the handles. You do, after all, have to counteract the torque of the auger digging into the soil. Both operators should brace their left side near the left handles to get their body into the act. Be sure not to dig too deep without cleaning the dirt out of the hole. If you go deeper than 12 in. or so, the used3.5hpelectricchainsawmotor auger will be extremely heavy to lift out of the hole, or worse, you can corkscrew the auger in so deep that it''ll get stuck. Photo 7 shows you what to do if that happens. Looking for a chainsaw for sale? We have tons of chainsaws to choose from right here! Not only do we have a huge chainsaw selection for you to choose from, our chainsaws are off the chain as far as discounts. We have a huge selection of cheap chainsaws.
|