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Week 5 (Sept. 26, 2018): Presentation #1 (Goals & Specifications) Reflection & Gimbal Motors


Today, we delivered the first out of three Senior Project Presentations. The objective of our presentation was to discuss our team goals as well as our refined, conclusive design specifications.

Although we stated, in our Presentation #1, that I would oversee the software side of the small-scale model and David would be in charge of the hardware, our duties will more than likely overlap with each other due to the interdependent nature of controls and mechatronics systems. In other words, a circuit and a controller are meaningless without the hardware, and the hardware, such as actuators, cannot be controlled without a programmed controller and driver. And, once again, our duties will also overlap with Small-Scale Bogie and Small-Scale Track, with more interaction with the Bogie team due to the bogie-motor connection.  

Having said this, at the conclusion of our presentation, we received some feedback from Dr. Furman. He brought to our attention brushless gimbal motors, as is used for the cameras found on commercial drones, as another consideration for the selection of the motor to be connected to the bogie. I performed some research into these types of motors.

Brushless gimbals are wound for very low speed (i.e. lots of turns of thin wire) and specifically made to be used in fine control applications. They are A good place to purchase them is at iflight-rc.com. The one found on the website, the iPower Motor GBM5208H-200T, can lift 4 kg-cm, which is equivalent to 0.392 N-m. They are 63 mm in diameter and 24.5 mm in height, making them much smaller and However, it does require 11.1 V to operate and is more expensive, compared to the cheaper 5 V servos I have experience with, making our decision between using a gimbal or servo motor undecisive once again. Although this website does discuss the advantages of each, we still have to consider the power requirement of each motor: 11.1 V will require a larger battery pack compared to 5 V. We will have to consult with the Bogie team to determine what kind of motor will be required to motorize the pod car.   

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