NXT Golf Ball Challenge

NXT GOLF BALL CHALLENGE

Function: The goal of the challenge is to construct a vehicle, using a NXT robot, that captures a golf ball from the loading area and deliver the ball under the bridge to the waiting container.

System: Hailee and I are going to try to get second fastest robot that can deliver the ball. We are planning to make the robot short so it can easily fit under the bridge. We are planning on attaching another motor so we can move the claw, which will easily grab the golf ball from the tee.

Trouble and Solution:

• The robot is too strong, so the ball is falling out easily.
• Lower the power
• Add a stick to the claw so the ball can be more secure
• Low accuracy
• If we fix the claw, we need to rebuild the whole thing.
• We decided that it was worth it!
• Time
• Working process…
• Raising the power

What we have learned from doing this project: Hailee and I were fairly new to working with NXT robots, so we thought this golf ball challenge would be a good opportunity for us to learn about the NXT program. Since we were not accustomed with coding and building, we sacrificed our lunches and SRTs to work on our robot. We had to “guess and check” the coding since we did not have a lot of idea on what the programming would do. Hailee mostly worked with the building portion of the project, so she became accustomed to Lego pieces. I worked a lot on coding, so I am more familiar with using the NXT program. If I could do this again, I would try to build our robot a little shorter. Although we wanted our robot to be long (horizontally)  and short (vertically) so that it would easily fit under the bridge, our robot was also so lanky that it added friction.  

Performance of Our Robot: In the beginning, our robot was unable to complete the pickup and drop off of the ball. We had to fix this complication through coding as well as rebuilding and redesigning. We tried countless designs, and, with each new design, a readjustment had to be made in the coding. We finally found one that was more consistent. From there, rather than starting back at square one, we built on top of each design to solve every new problem. For example, as we sped up our power, the ball kept whipping out of place, so we added a stabilizer to our claw. Although it ended up being a little more bulky, our time was great, and our runs got increasingly consistent and successful.

Summary of Our Official Runs:

Behavior	Run #1	Run #2	Run #3	Run #4
Moving towards loading area	☑	☑	☑	☑
Stopping at pickup	☑	☑	☑	☑
Capturing golf ball	☑	☑	☑	☑
Moving on the pickup	☑	☑	☑	☑
Moving on the goal side	☑	☑	☑	☑
Stopping at goal	☑	☑	☑	☑
Dumping golf ball	☒	☑	☒	☑
Time (sec)	Not Successful	7.69	Not Successful	6.47

Daily Blogs

Day 1 8/31/2016 :

Today, Hailee and I got our first project of the year assigned. This challenge needs to be solved using the NXT robots. The goal of the challenge is to pick up the golf ball from the tee box, carry it across the fairway, and drop it in the box. In order to accomplish this goal, the robot needs to be able to move, grab, turn, and drop. We started out by drawing a concept sketch on a paper. Then, we constructed the prototype.

Day 2 9/2/2016 :

Last couple of days, Hailee and I came into the makerspace everyday to work on our challenge. As a result, we were able to build a robot that could pick up the golf ball, go back, turn, go under the bridge, turn, and drop the ball inside the box. However, we had a trouble with accurately placing the ball inside the box. So, today, we worked a lot on building. We tried redesigning a couple of times, and, with each new idea, we had to adjust the coding. After a few new ideas, we had no luck and decided to retry our first claw. After identifying the initial problems with the first claw, we were able to quickly eliminate them. But, sadly, on our first official trial, we forgot to secure the joints of our robot, so the ball did not make it inside the box but landed on the brick. Next time, we need to focus more on the coding and less on the building of the NXT to get everything just right.

Day 3 9/7/2016 :

Today, Hailee missed school, so I worked on the robot by myself. For some reason, our robot stopped working. There were two main problems: the golf ball falling out as the claw lifted itself up and the ball landing on the brick in front of the hole. I solved the first problem by making a “gate” with axils on the side of the claw. Before solving the second problem, time started to run out. So, I decided to do the second test run. God must have been in my favor because Sailee Robot decided to work and finished in 7.69 seconds! In fact, Sailee was the second fastest robot in the class! I was very proud and happy.

Day 4 9/9/2016:

Today in class, we worked a lot on the coding for our NXT. We focused on the precision of the ball drop off and initially had trouble with all the different angles. We also focused on the coding for making our NXT faster, since we already got in a successful trial. At the end of class, we were able to make our NXT faster, extremely more reliable, and consistent with its work. Since we sped up the motors, we also had to account for the faster turn when the ball was in the claw. The turn was so fast that the ball kept whipping out of its grasp. We modified it by placing a bar next to one side so it could keep the ball in place. We were able to make our time over a second faster, and took second place! Our final time was 6.47 seconds.

Our concept sketches

We were number two out of all 48 students!
After our first trial, our time was that listed
above, and our second trial got us to 6.27 seconds!

Our coding for the project