The main picture in this section is the robot with the NXT brick disconnected. I originally programmed this robot in RobotC, but since most people don't have it I also wrote an NXT-G version of the program. Due to the limitations of the language, the NXT-G program doesn't perform as well as the RobotC one. The RobotC program moves the robot faster and still reacts fast enough to make its impacts so gentle that a cat doesn't mind getting hit (This was experimentally confirmed). The RobotC program is a comment on the NXT-G program for those of you who have RobotC.
The movie has two parts. The first shows the robot finding its way out of a tight corner and the second shows it navigating a forest of table and chair legs.
Since the robot turns a random value each time I ran each segment twice, but it escaped fairly quickly each time.
Instead of posting instructions like I often do, I decided to post a section on each sub-assembly of the robot. The pictures show each sub assembly while it's built into the robot, but they zoom in on the parts you need to see. The first two pictures in this section zoom in on the left gearing and wheel assembly from the bottom. The next two zoom out a bit to show the connections between the 2 assemblies.
The first picture in this section is a top view of the right beam connecting to the right motor (it is a 13 unit beam). The second shows the two wiring brackets I made to hold the touch sensor wire (You can ignore those if you want). The third picture shows a rear view of the right beam connecting to the rear beam (and the caster wheel). The fourth shows a bottom view of the whole rear beam. The fifth zooms in on the rear NXT mounting brackets
There are only three pictures in this section but there's a lot to build. The first picture shows the center of the top, with NXT mounting brackets and the base of the front structure (the beams that stick off the lower left are 13 units long). The second picture shows the front of the 13 unit beams where the connect to a 15 unit cross beam. The third picture shows how the touch sensors are connected to the cross beam.
The first picture shows another 15 unit cross beam that connects to the front structure. The second shows a 9 unit beam that connects to it. The third shows 2 seven unit beam that support the bumper.
The first picture shows the center of the front where a 7 unit beam holds four 13 unit beams together. It also shows the 15 unit beam and the zamor launching rods that increase the bumper's area. The second picture shows where the bumper connects to the left touch sensor. The third shows where a few angle beams connect to the long beams (and another zamor launching rod) The fourth picture shows where a few more angle pieces thread through the support structure to complete the bumper.
This robot is great at avoiding stuff for only having 2 touch sensors. It is by far the best touch sensor explorer I've ever made or seen, for its robust design and for it's effective method of avoiding objects. It can get itself out of the toughest of situations. If I could have you build any of my robots, it would be this one because so far it has been the most fun to play with.