Individual Blog Week 6 (7/5 - 7/7)


Although this week was a shorter week, I was still able to make progress towards the tilting mechanism. The first thing that I did was make concept sketches and pitched ideas to several other people. After culminating the suggestions that I was given into one single plan, I was able to design a tilting mechanism that performs as expected within Solidworks. As shown in Figures 1, 2, and 3, the DC motor is able to move the entire frame with the use of bevel gears and sprockets. Other sprockets are mounted onto the frame to promote tension throughout the entire chain. I was not able to include an actual chain within the assembly due to the nature of this system. Solidworks is not able to have open ended chains perform dynamically. However, this does not detract from the viability of the mechanism.

After creating the CAD model of the system, I began writing code for the tilting mechanism. This includes a 9 DOF accelerometer and gyroscope sensor, several red LEDs, and a DC motor. I utilized a fuzzy control system to facilitate the operation of the tilting. The LEDs were used as callouts for the states of the entire system with the DC motor tilting the bottom frame to bring the system back to equilibrium (parallel to the ground). The main operation that this program performs is change the position of the bottom plate shown in Figure 1. This position needs to be parallel to the ground at all times, especially at the 17 degree incline to have a comfortable, and enjoyable riding experience. To test my program, I tilted the 9 DOF sensor in the y-direction, which will simulate pitch within the system, to give inputs to the rest of the program. Testing was done until everything worked as planned.




Figure 1. The tilting mechanism that controls pitch.

Figure 2. Positive pitch from the tilting mechanism.


Figure 3. Negative pitch from the tilting mechanism.


Figure 4. Using pointers to allow multiple functions to run consecutively within the main.

Figure 5. A portion of the fuzzy control, which shows the different states.


Figure 6. The main loop within the tilting program.









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