Lab 7 Formula0001 Racing Robot (version 0) sponsored by Tivioli Page 7.1 Jonathan W. Valvano Lab 7 Formula0001 Racing Robot The robot materials were funded in part by a grant from Tivioli. Goals • Design a robot that can move forward/backward, and turn left/right, • Interface motors, and sensors to two microcontrollers, • Implement pulse-width modulation using output compare to adjust power to the motors • Employ input capture interrupts to measure distance and motor speed, • Write low-level device drivers for the motors and sensors, • Develop a high-level control system, • Use communication skills to work effectively as team. Review • Text book Chapters 8 on interfacing motors and sensors • Lectures 16-23 on input capture, PWM, motors and control • Textbook Chapter 10 on control systems, • Construction guide for the erector set, • Data sheets for L293, GP2Y0A21YK, HC-SR04, and Ping))). Starter files • See Lab6.sch To win this competition, your team must combine mechanical, electrical and computer skills. Each robot has one switch (in addition to the reset switch) that the students will push to start the competition when instructed by the TA-referee. The reset switch (the normal hardware reset) should cause all motors to stop and will be used for safety purposes. You will push your start switch once at the start of the competition signifying the start of the 180-second competition. You are allowed up to three repair events on your robot during the 180-second competition. Otherwise, the robot must run autonomously. There can be no wireless input commands or buttons pushed during the competition. Both microcontrollers must run using your RTOS with blocking semaphores developed in previous labs. It must also employ digital control in an appropriate manner. Examples of appropriate control are travelling at a constant speed, travelling at a constant angle to the wall, and travelling at a constant distance to the wall. Example control algorithms include incremental, proportional-integral and fuzzy logic. If you are not sure whether or not robot satisfies this requirement ask you TA. The Track There are seven example tracks posted on the class web page. You can view these tracks by looking at the pdf versions, and you can create your own track by editing the PCBartist PCB files. Figure 7.1 shows one of the tracks, which is made with 54 pieces of wall. The wall pieces are 32 to 33 inches long, made from cedar wood about 3.5 inches tall and 3.5 inches wide. The floor will be the carpet of the 3rd floor lounge. The width of track including straight portions and turns will vary from 29 to 35 inches. Each lap will be divided into 5 to 10 segments, demarked by the milestones and signified with blue tape on the walls. Robots will be started in pairs, with a wall either on the left or on the right. Figure 7.1. Design of Track 7. Milestones are labeled with blue tape on the wood.Lab 7 Formula0001 Racing Robot (version 0) sponsored by Tivioli Page 7.2 Jonathan W. Valvano The Race One, two, three, or four robots will race at the same time. Your score will be based on both speed and accuracy. Your starting location will not be known until race time. Two robots will begin side by side at a milestone as chosen by the TA-referee. The TA-referee will tell you which milestone to start up and which direction to travel. The students will have 60 seconds to place their machines onto the track from the time the TA-referee calls them to set up. The front-most part of your robot must be at the milestone line at the start, but its lateral position and orientation are up to you as long as you are on your half of the track. When the teams are ready, the TA-referee says, “Go”, and each team will push its start button to activate its software. If a robot fails to start as expected, the TA-referee will award one false start, and the race will be restarted. Two false starts constitute a disqualification. The remaining robots will be allowed to continue. The powered portion of a competition will last 180 seconds. Your robot must stop all moving functions at the end of 180 seconds, and any robot that continues to move after 180 seconds will lose two points. One member of the team will be designated as the mechanic. This member will be allowed to make up to 3 repairs during the race. If your robot needs a fourth repair it will be disqualified and not allowed to continue. Examples of repairs include but are not limited to: 1) reorienting the robot because it is going the wrong way; 2) moving a robot because it is stuck up against a wall; 3) reconnecting a loose wire; 4) fixing a mechanical malfunction; and 5) resetting the software. Repairs must be made in such as way as to not impede the progress of the other robots. Because of the speed limit in pit row, all repairs incur at minimum of a 15 second penalty. A team member shall count down 15 seconds out loud during the repair. After the repair, the robot must be placed back on the track at a position behind where it was picked up and not within 2 feet of another robot. Each milestone is signified by tape on both sides of the track, creating a virtual line across the track. You will start with the front of your robot at one of these virtual lines. Let M be the number of milestones passed. S will be 0 if your robot stops after 180 seconds. However S will be -2 if your robot does not stop after 180 seconds, and S will be -2 if your robot is disqualified. Your score is calculated as Score = M + S To achieve a milestone, any part of your Frisbee disk must cross the milestone line. You can achieve a milestone only once per lap. “Going the wrong way” is defined as a robot making significant progress in the wrong direction. If the mechanic thinks your robot is “Going the wrong way”, he or she should pick it up, wait 15 seconds, rotate it into the proper direction, put it down at least 2 feet from other robots. For example, if your robot passes 7 milestones but does not stop moving after 180 seconds, then your score will be 7-2=5. The TA-referee will disqualify a robot if it does not appear to be making progress or if the TA-referee thinks you are using repairs inappropriately. The TA-referee will disqualify a robot immediately if a robot presents physical danger to spectators, itself, or the opposing robot. The motors have plastic gears and will break