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Week 21 (Mar. 06, 2019): ME 195B - Presentation #1 (Prototyping Stage) Reflection

Today, we presented our first presentation of our second semester of ME 195B - Senior Design Project, making it our 4th presentation overall, throughout the entire duration of senior project, since last semester. 

Please refer to our Presentation #1, embedded below. 

Up to now, we have gathered all of our major components and are starting to prototype one small-scale podcar. Although, if we find that we need to buy a smaller component, we do so immediately to get ahead of the delivery time. Besides the gimbal motor and the accompanying ESC (electronic speed control), we have tested all the parts and have found that they all work individually. 

Despite the fact that there's limited information on gimbal motors on the internet, we found some Arduino code to run the gimbal motor and ESC. However, regarding the connections, we have all but one connection - the connection between the ESC and the battery; all we need is an XT60 connector to connect the ESC to the battery; it is currently in delivery. After the presentations today, we will make the gimbal motor connections and test the motor. 

Following our Presentation #1, we received some questions from Dr. Furman primarily about the gimbal motor. Because we don't yet have the XT60 connector, and thus haven't been able to test the gimbal motor, we could not answer his questions properly. 

Dr. Furman asked us two questions that we would now like to retroactively answer. 

The first question was if we were sure that gimbal motors are intended to be run slowly. Our answer is: not necessarily. The speed can be controlled, albeit to a limited degree, with a potentiometer connected to the Arduino. The Arduino will read analog readings from the potentiometer as its knob is turned. Accordingly, the Arduino code will set a proportion to scale the potentiometer readings to a speed value to write to the ESC. 

The second question he asked us was if we will be controlling the speed of the motor. To answer, we will find a good speed and then set the potentiometer reading permanently. We will also make the motor start at a lower speed, and then accelerate to the desired speed. We will accordingly gear down the motor, as it seems the lowest possible speed of the gimbal is still too fast. 

After completing these prerequisite actions, we will then ensure all the components to run together and complete one podcar. We will have to complete one podcar prior to Presentation #2 so that we can present good progress, and from there, it will be easier, as we would simply have to replicate our actions to the other podcars.

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