In the robot testing class on 13th week, the robot was tested firstly on the prescribed tennis table, it is found that table-top friction on the tennis table was especial smaller than the ground. And two preset rotation angles in the robot program could not reach the desired angle. So some adjustments related to the angles of two swerves and the straight running distance were adjusted during the seven-minute test period. Finally, the robot successfully passed the bridge deck and went through the bridge opening.
In the formal test, during the first time: the robot successfully passed the bridge deck, but the tire deviated from the track when drove down the bridge deck. This error resulted in the reduction of the second time turning angle and ultimately the robot impacted the lower support part of the bridge, it also failed to pass through the bridge opening. During the second time: the robot successfully passed the entire bridge deck and then two perfect turning movements were carried out.
Finally, the robot went through the bridge opening and the our team got a score in this test. The whole second process was perfect and there was no big deviation compared with the expected driving path. During the third time: the robot successfully passed the entire bridge deck, but the angle deviation occurred during the first swerve. The tire rolled over the bottom of the bridge, resulting in the inappropriate position for the second swerve. Finally, the robot impacted the lower support part of the bridge and failed to go through the bridge opening successfully.
As for the bridge made by the bridge team, it was very stable during the three tests and there was no sliding phenomenon happened when the friction coefficient of the test surface was reduced. It had provided a strong guarantee for the faultless completion in robot testing. By comparing the results of three tests, the shortest time for the robot to successfully complete the process was got form the second test: 10.9s. Considering that the size of the robots was larger than other teams and the length of the bridge was longer, the total time ranked lower in all teams. The bridge of Robot Downey team weighed 11 ounces and it was lighter than other teams (but not the lightest). The final score was 294 points, which was based on the factors of test time and bridge weight. Although our team had successfully completed the robot test, the total score was not very good compared with other teams and we finished seventh.
?Performance of team members
Our team had a clear division of labor and everyone was positive. All of the members in the Robot Downey were united. Although there were a little frictions sometimes, each member always get together to solve them by discussing and interaction. Everyone put forward their own suggestions and actively completed their own tasks.
?Lu Binwei was mainly responsible for the overall design of the bridge which included the overall structure of the bridge and the basic unit composition of the bridge. He was patient with the design and showed a rich imagination.
?Wang Yizhi was mainly responsible for the the robot design. Through his unremitting efforts, the robot had been modified and tested for uncountable times to achieve the best prototype. He was extremely patient and creative.
?Zhao Yixin was responsible for the programs which enabled the robot to pass the bridge deck and bridge opening smoothly in the shortest time. It took a lot of time for the robot to complete the correct movements with the shortest time. He was confident and not afraid of difficulties.
?Fan Haiwen helped Wang Yizhi to design the robot. She come up with the idea that the robot’s main controller could be leaned back to lower the center of the gravity. There’s no deny that this outstanding idea had brought our team lots of benefits.
?Xu Yi helped to design the bridge. She put forward the idea that the width of the bridge deck and the slopes could be made with the least area to support the wheels. It was unnecessary to cover the whole surface and this method lightened the bridge’s weight greatly. Her idea was usually beneficial at the key moment.
?Wang Ruimei is team the leader. She had drew up a detailed schedule to guide other team members. She was responsible for counting progress and interaction with other teams. What’s more, she recorded all of the prototypes and data to make preparation for the report. She always identified the problems in time and expressed her perspectives patiently.
?Yang Yingping and Liang Fuyan were responsible for sticking the basic unit structures and helping to assemble the bridge. They were also responsible for simple stitching of the robot.
? Level of objective completion
Our team had accomplished all the objectives satisfactorily.
?The bridge team had built a bridge with reasonable structure and light weight which was also similar to an arch bridge.
?The basic connections of the bridge had been designed to be cross-connected and this devise had improved the bearing capacity of the bridge.
?The production team had assembled a low-gravity robot supported by four rubber tyres with good climbing ability.
?With tightly connected programs, the robot had passed the test successfully in the robot testing class.
? Problems and errors
?The length of the bridge was too long because of the large size of the robot
?The front wheels of the robot were not stable enough and it sometimes made the robot run curly.
?Whether the robot could complete its whole journey depended largely on the original position, so the fault tolerance rate was low.
?The overuse of chopsticks resulted in a overweight bridge.
?The interfaces between the bridge deck and the slopes were a bit harsh which might lead to the deviation from the pre-selected orbit.
?The supporting structures on both sides were not completely symmetrical which would cause the unstability of the whole bridge.
By collecting network information, the team members learned about the relevant principles of robot running and through the process of reading splicing instructions, the design team designed the first prototype of the robot. After assembly, the robot was tested. The corresponding shortcomings were corrected and improved to minimize the errors in the process of running. Finally, the final prototype of the robot was determined.
By collecting information from the internet and reading some relative books, the team members had a basic understanding of the general structure of the bridge. The design team drew up the design draft based on the collected information. The bridge team completed the first prototype of the bridge according to the design draft and then began testing. During the test, the shortcomings of the bridge were excavated, improved and then a few of new ideas were constantly added. The final prototype of the bridge was finally determined.
In the robot test, the robot successfully went over the bridge deck and then went through the bridge opening. The total time was 10.9s.
First, various factors should be taken into account in the brainstorming and design process. A lot of influence related to the final results is important. For example, in the process of designing the bridge, we only considered the weight of the bridge but ignored the impact of the bridge length on the robot’s crossing time. Secondly, communication skills and the time of exchange the ideas should be improved in team cooperation so as to facilitate faster progress of the project. Thirdly, in the design of the bridge, the weight of the bridge should be reduced as far as possible to make the bridge deck shorter and narrower so that the robot can pass through the bridge deck and pass through the bridge opening in a shorter time. Fourthly, it would be better if the chopsticks were transferred from the vertical direction to the horizontal direction and laid on the bridge deck and slope. These changes would decrease the friction. Fifthly, the third chopstick doesn’t need to be glued between the other two chopsticks, because the glue is sticky enough and the addition of the third chopsticks will increase the weight of the bridge. Sixthly, the robot’s large size has led to a heavier weight, which affects the driving speed. It requires a higher demanding for the supporting part of the bridge, which also lead to the increase of the bridge’s volume. Seventhly, the design of fixed structure part for the robot is not perfect enough and it is likely to cause the deviation of the driving path due to the splicing error. Last but not least, the design of the turning structure of the robot is inadequate and it can not make wheels rotate relatively flexible.