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.

Comments

Week 30 (May 8, 2019): Prototype Evaluation Day, Final Circuit, Incorporating 3D printed parts, Final Presentation, Posters, & Maker Faire

Today, we held Prototype Evaluation Day. Like the rest of the senior project classes, the advisor walks around the classroom, evaluating the senior project apparatuses, asking the student teams to demonstrate their devices, and explain their design, though processes, and results. Dr. Furman and Ron examined and inspected the Full-Scale model, then the Half-Scale model, and lastly, us, the Small-Scale Team. We had completed our circuit to power one pod car and one of the two induction charging stations prior to Evaluation Day, so we were able to successfully demonstrate the pod car driving around the track as well as the induction charging. While we were still troubleshooting issues with the tablet’s Raspberry Pi communicating with the Arduino, the Arduino is still capable of operating on its own, so we could at least demonstrate the motor driving the pod car around the track and through the offline stations. Depicted below is our final circuit that powers the pod car: Dep...

Week 28 (Apr. 24, 2019): Final motor selection – Mini-Stepper Motor

Since last week, we have been trying to run the new brushless DC motor; however, it is still difficult to control, let alone its speed. Therefore, we had to pursue our alternative motor, the mini-stepper motor that runs at 5V. Found in Arduino starter kits, this mini-stepper motor is accompanied by its dedicated motor driver board, the ULN2003, which is a chip containing a series of Darlington pair transistors. An image of the stepper motor and the ULN2003 board is shown below: Sources: https://www.adafruit.com/product/858 https://www.amazon.com/gp/product/B01CP18J4A/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1 We were able to successfully run the new mini-stepper motor with the sample code included with the Arduino starter kit. One benefit to using the sample code is that it utilizes the Stepper library’s functions. One use function is the setSpeed( ) function, which allows the user to set the RPM speed of the stepper motor. We found that the ma...

Week 27 (Apr. 17, 2019): ME 195B - Presentation #2 (Prototyping Stage Continuation) Reflection

Today, we completed Presentation 2, which is our 5 th presentation overall, throughout the entire length of senior project, since last semester. Please refer to our Presentation #2 slides, embedded below. Covering the continuation of our prototyping efforts, we discussed progress on hardware acquisition, integration of components into a working circuit, and programming. Regarding programming, we were still working on the communication between the Raspberry Pi and the Arduino. And while the circuit is also coming together, there was one piece that gave us problems yesterday: the gimbal motor broke and so we had to order another motor that is not a gimbal but is still a brushless DC motor. An image of the new motor is found in our presentation slides below. While this was disheartening at first, we found that the gimbal is not intended for continuous rotation, but instead for precise movement, as they are used for cameras on drones. However, this was still a setback...

Patrick Barrera's Progress for Spartan Superway

Search This Blog