Well...I must say this is not perfect, but it is nonetheless impressive :)

This week, I made considerable progress in the assembly process of the legs of my walker. First and foremost, I was able to complete the task of putting all 4 legs together. I also made a number of improvements on the design of the joints for the walking mechanisms and the legs themselves. For instance, I replaced the screws that were meant to fill the gaps with washers of the same size. One of the main issues I discovered is that whenever the walking mechanism was rotating, the screws would rotate as well. Depending on the orientation of the movement, the screws would tighten or loosen the joints. This would either cause the whole mechanism to fall apart or would led to it being stuck. Another change I made to the legs was the replacement of some of the screws with longer ones. This allowed me to better secure the joints with lock nuts, which would not have been possible with shorter screws. Aside from the changes made to the joints, I also managed to complete the soldering of all four motors I needed for the locomotion of my walker (the last one has yet to be delivered). Initially, I had some trouble in securing the wires to the metal connectors of the motors due to their relatively small size and the meticulous work soldering required. After a while, however, I became more accustomed to it and I was able to press on and complete this task in time. Shortly after soldering wires for the motors, I moved on to work on the design of the superstructure. Following Aaron's suggestion to lower the center of mass, I came up with a design in which the top of the hull (which is pieced together with the lower half using screws) was joint to the boxes located on either side of the leg compartments. By doing so, I would decrease the height at which the center of mass is located while leaving the design relatively unchanged (initially, the hull was supposed to go on top of the craft; hence, the screw holes are located on the top side of the compartment). Furthermore, this hull design would allow me to disassemble the whole robot if maintenance was necessary while still offering a strong link between the legs and the superstructure. In preparation for future plans to incorporate the ability to turn to my walker, I also separated the hull into 2 pieces with linkages in the middle that can be modified to either allow for a fixed hull or free movement of the front part of the robot. In next week's periods, I plan in finishing the design of the hull and to scale it to the appropriate size. Then, I would print it out, assemble it, and test out the walker's ability to stand and move without the help of a supporting piece. Once that is done, I will then work on designing the feet for my robot. I am very excited and look forward for the completion of my walker 

^^

This week, I was able to complete the assembly and testing for the prototype. Despite some delays in the process of putting the prototype leg together, such as the fact that some of the pieces had to be redone to fit the leg, I managed to complete the prototype leg in time for testing. After finishing the assembly of the leg, I went to solder wires used to link the motor to the motor shield. Once this was done, I was able to connect everything together to test out the functionality and effectiveness of the leg. The results were satisfying, as the prototype leg proved to be able to stand on its own while bearing weight. It was also capable of recreating a walking motion and was much less prone to jamming in comparison to the legs I built for last year's walker. Pleased with the results of the testing, I decided to move on to work on the legs that would be used in the final iteration of my robot. While I was able to print out all of the pieces needed for assembly, I was not able to complete all of them in time and I only had time to put the main parts together. In the upcoming periods, I plan in finishing these legs as soon as possible and to design a body/frame that would hold all 4 legs together. I also considered about lowering the center of mass, as  suggested by Aaron, and thought about the different types of feet, both of which  would help giving the walker better stability. All in all, I believe that I made considerable progress during this week's classes.

This week, I made huge progress in the building process of the prototype of my leg. Initially, my first attempt to assemble a prototype of the leg failed. The structure I used was too weak and it could not hold the weight of the motor. In addition, it was separated into different pieces I had to glue together, making it very hard to assemble. It was also not very practical, as many pieces surrounding the motor were to be fixed permanently onto the leg structure. This would have been problematic if a change of motor was required, as I would have to strip these pieces away in order to access them. As a result, I decided to change my design. In my second attempt, I simplified the process with which the wood pieces were assembled by simply attaching them together with screws. It proved to be effective and yet simple. Once this problem was fixes, I moved on to attach the leg to the structure. At first, progress was slow, as I was not very accustomed to work with small pieces and screws. However, I managed to accelerate the pace once I got used to it and I was able to finish the assembly the majority of the leg structure pieces. In future classes, I plan in adding the motors and in linking them to the arduino and motor shields. I will then test the leg's capacity when powered by a motor. Once that is done, I plan in designing the foot and the body. So far, I am very satisfied with the progress of my project and I look forward for the completion of my new Walker

This week, I started by writing down a plan of action that I would follow through the course of this semester. I had several goals in mind, such as making my robot being able to stand by itself or to give it the ability to make turns instead of being restricted to walk in straight lines. Then, I worked on sketches of the legs. The legs had to be entirely redesigned, as they had shown to have several major issues on the first final iteration of my robot. For instance, they were prone to jamming and the joints caused high friction whenever movement was done. As a result, I wanted to come up with something new. After I made some sketches of how it might look like, I moved on to the testing phase. In contrast to the testing done on my first iteration, which involved building incomplete mockups of the body and leg out of cardboard pieces, I decided to use digital softwares to test the reliability of the legs. I chose to use this method because it would save on time and materials. Furthermore, the mockups were not very reliable, as they would often bend or break when exposed to forceful motions. On the other hand, while digital software offer more advantages when testing, they were not without their drawbacks. For instance, I had to learn how to use it and had to memorize the commands. Furthermore, I had quite a lot of trouble to work with the testing part of the software, which slowed down the development process. Next week, on my trip to Boston, I will try to work with the Nuvu educators to come up with a satisfying design for my legs. I would also start to plan on how to implement turning in my design.

Looking Good ^^

Side note: the orientation of the leg has yet to be determined; it is subject to change

This week, I participated in the midterm review presentations as a guest presenter in the cinemagraph studio. As a result, I only had one period left to work on my walker. In the course of the second period, I tried to fix the issue with the battery drainage issue by using 2 separate motor shields and power sources. Despite my high hopes that this might solve the problem, it did not avail to anything. On the other hand, half way through the period, I found out that one of the batteries exploded and caused a leakage of lead. In respond to this, I decided to change the batteries, but I ran out of time to test out whether this was the source of the drainage problem or not. 

While working on the issue with the electronics, I was also making progress in solving some of the mechanical issues that appeared during my first tests last week. Notably, I changed the configuration of the washers on all four legs to prevent an undesired tightening or loosening of the nuts when the leg is moving. I also changed the way how the legs and motors were secured. Instead of having to add a specific piece to lock the motors in place, I simply inverted the orientation of the screws that were meant to fasten the leg compartments to the superstructure and used them to prevent the motors from moving up and down. By doing so, I improved the functionality of the legs when in motion while adding no further weight to the walker. Furthermore, I also ordered some nylon screws that would be used to reduce the weight of the robot. As for the electronics problem, I arranged a meeting with David via Skype to gain more insight on the matter.