Week of 02/01 - 02/07
Alexa, Anais, Manohar: We are continuing to develop our project idea and proposal. One significant challenge is figuring out what our tasks will be, because we have to learn more about Arduino before we know what tasks it will involve and how to assign each task accordingly. Another significant challenge is determining what materials we will need to purchase, because we are still in the process of learning/figuring out how to create out project. This week we also struggled to figure out how to make our wiki pages, but we were eventually able to figure it out together during class.
Week of 02/05 - 02/08
Alexa, Anais, Manohar: This week we are still working on our project proposal. A major challenge has been trying to foresee what tasks and materials out project will entail, because we do not yet know how to build our project in the first place. We are starting to research the capabilities of Arduinos and of different kinds of sensors to try get a better idea of what we will be working with. With some research and brainstorming, we came up with our budget list with our initial ideas of some materials we might want to use to build our project. We have spent a considerable amount of time developing a list of tasks we will need to complete and a list of items we will need to purchase. We have also worked on developing our project's main objectives and goals, which can be found on our main project page.
Week of 02/09 - 02/15
Alexa and Anais: In this video, we demonstrated our Arduino skills by connecting an input to an output, allowing a light to flash at one-second intervals when we disconnect the jumper from ground and reconnect it to Pin 9. The light at "L" flashes for one second when the input and output are connected.
Week of 02/16 - 02/22
Alexa, Anais, Manohar: This week, we spent a lot of time putting together our project presentation for class. We also did more in-depth research on what kinds of sensors we can use. Originally, we had thought about using ultrasonic sensors, but this posed multiple issues/limitations. Ultrasonic sensors would not be effective for communication between two devices in busy environments that are not in direct line of sight, because objects between the sensors would interrupt the ultrasonic waves. Instead, we decided to use bluetooth instead. We spent a lot of time looking at different sensors, and we came across the HC-06 Bluetooth Module, which we think will suit the needs of our project.
One downside of this bluetooth module is that the range is limited to about 30 feet. However, an upside is that the bluetooth module will be better suited for busy environments, and it will be able to transmit information despite physical interference between the devices. Now that we have chosen what kind of sensor we want to use, we need to order it as soon as possible so we can get some hands-on practice with it and figure out how to use it for our specific project. One upcoming challenge will be figuring out the phone side of the system of devices. The bluetooth module product description is not exactly clear, but it seems that there are already pre-existing apps in place that we can use for the user interface on the phone side of the system.
We also spent multiple hours developing our project presentation: Link to Project Presentation
Week of 02/23 - 03/01
Alexa, Anais, Manohar: Last week Manohar ordered the HC-06 Bluetooth Module and the alarm buzzer. The buzzer still has not arrived in the mail, but we have received the Bluetooth Module. We used a breadboard to connect the bluetooth module and the Arduino, and then adjusted accordingly using resistors. Our weekly goal is to establish a connection between the bluetooth module and a cell phone. We are using the Blueterm app on an Android to verify that a connection was made between the bluetooth module and the cell phone. We also updated the code to account for misreads. For instance, if the bluetooth device were to lose connection from a faulty signal while it was still at close range, the buzzer would ring, and it would be a false alarm. We are adjusting our code, so that when there is a series of decreasingly weak signals detected, that is when the buzzer will ring.
Manohar: The first goal was to make the LED pin(pin 13) on the arduino uno light on and off using the Blueterm app on the android device. To accomplish this, we made a sketch on the arduino IDE through which we could control the arduino through the app once the bluetooth connection was established. The sketch also contained a chunk of code that would enable us to receive output messages on our android phone along with the activation and deactivation of the LED pin 13. This scheme can be adjusted in our project where we can use the alarm buzzer instead of the LED pin in order to know if the bluetooth connection is still established or that data can still be read from the arduino by the phone. We also want the output message on the phone to show if the signal strength is continuously decreasing or increasing so that we can be absolutely sure that the kid is going away from the mother's phone. By creating a sketch with bunch of conditions and a loop to compare signal strength values, this can be achievable and is our next goal.
We also started to work with AutoDesk Inventor this week.
Alexa: This week I spent a few hours familiarizing myself with the 3D modeling software Autodesk Inventor. I practiced making pretty basic objects, and then I practiced making hollow objects. We are planning on using the 3D printer to create a box/case for the device that the child would presumably be holding. This case would have to hold the Arduino with the bluetooth module, wires, and speaker (which has not arrived yet). Additionally, we are most likely going to switch from using the Arduino to using the mini Arduino. Because we don't yet have the exact measurements, I did not attempt to begin drafting the final version of the case, but rather just began learning how to use the software. A tentative idea is to print a case shaped like a treasure chest, so that it can be opened and it is appealing to a child. I also realized that we will have to make small "speaker" holes in the box so that the device inside can project the noise outside the box more efficiently. I also plan on printing a loop at the top of the box so that it can be attached to a key chain.
Week of 03/02 - 03/08
Alexa and Anais : Started developing designs for the child's wearable portion of the device. We decided on a treasure box shape for the exterior of the box. We are working to develop the most efficient way to clasp the box. As of now, we are strongly favoring the idea of having an attached loop to both the lid and the base of the box, where a key chain ring could attach them both. Our current challenges consist of being able to 3D print the loops onto the side of the box and lid because the angle doesn't follow 45 degree rule.
In terms of designing the box on AutoDesk: We made a compartment space in the box by these steps: 3D model: modify: shell Protrusion: We made a new work plane on the front surface of the box and sketched a 2D rectangle and extruded that from the work plane.
Alexa : One design challenge we are facing is how to attach the lid to the base of the box. Ideally, we would like to have them attached by something bendable, but it is unclear whether the 3D printer can accomplish that. Another design challenge is making sure that the lid and bottom are perfectly aligned. As you can see in the screenshots below, the bottom will have a protrusion with a hole coming from the front. The idea is that the top will have an aligned protrusion + hole so that we can close the box by placing a key ring through both (aligned) holes.
Week of 03/09 - 03/15
Week of 3/16 - 3/22
Alexa & Anais : This week we made a lot of progress on the 3D modeling and design. Instead of trying to create a lid that sits on top of the box, we are going to design a lid that slides into the box from one side. We still intend to maintain the treasure box shape/design, but this orientation will be much more easily modeled and more likely to be successful overall. Despite the simplicity of the concept, it has been quite difficult and time-consuming to create the model, because the details are very specific. Further, even after all the work we have put in this week, there is a good chance we will need to go back and readjust the dimensions of the box to be more specific to the device sizes.
Some upcoming challenges will be printing the box with the "perfect" dimensions such that the lid and base can smoothly fit together and slide into one another. We pretty much have to guess how much excess space to leave between the parts so that they fit together without being too loose or too tight. It might be a bit laborious to adjust these measurements because it will require us to print out the whole model, assess and make adjustments, and then re-print the whole model until we get it just right.
Week of 03/23 - 04/05
Alexa, Anais, & Manohar : This week we decided to switch from using the mini Arduino to using a regular size one instead. We struggled to fit the bluetooth module, speaker, and battery to the mini Arduino so to alleviate the space issue, we will be moving forward with the regular-sized one. This change affects the overall size, durability, and practicality of the device. Ideally, a smaller device is more portable and durable (especially for a child), however we need to move forward with our project.
Alexa: This past week I also ordered a 9-volt battery , clips with leads, and a toggle switch that will allow us to turn the Arduino on/off. Using the instructions and suggestions from this website we will connect the red lead from the battery clip attached to the 9-volt to the Vin pin on the Arduino, and we will connect the black lead to a ground pin. The toggle switch will be in series with the battery so we can control the power from the battery to the Arduino. We will likely do so by soldering the toggle switch to the red lead.
Because we changed from the mini Arduino to the standard sized one, I also had to make large readjustments to the dimensions of the case. I spent close to six hours in the lab making all of the final adjustments to the model so we can print the first version of our case. I also cut out a holder for the speaker head and a small hole for the sound to get out of the box. The thickness of the walls of the box is 0.3 inches all the way around. To avoid making the wall to shallow in the speaker holder, I cut a hole only ~0.2 inches into the wall, and we will like end up hot gluing the speaker (which is 0.4 inches wide) into the space so it will not fall out. I also made sure to add extra clearance inside the box based on the measurements of the Arduino as well as 0.03 inches of clearance between where the lid will slide through the box.