Overall Progress
- Created our Project Design Slides
- Mobile app initial framework created and basic UI is in place
- Picked out parts for TA approval and review
Risks & Management
A major risk that has come up this week is that GPS does not work accurately indoors. We have verified this feedback and have now chosen to use a different shopper-tracking mechanism: Ultra-Wideband (UWB). This is expanded upon further in our design changes.
When searching for parts to purchase for our project, we realized that a lot of the robot chassis and other necessary components would arrive, at the earliest, after Fall break. Thus, we had to work around this and choose parts that would specifically arrive on time, primarily from Amazon, and integrate well with the rest of our systems.
A hardware risk that has emerged is that the motors in the robot kit might not have enough torque to allow the robot cart to maintain max speed with 30lbs of groceries. Since these motors are included in our robot’s kit, we will plan to use them for the basic testing and then subsequently upgrade our motors after testing, if needed. We are also looking into other motor options we’ll buy if necessary. We will have to consider how the new motors would fit into our robot’s design – for example, how to attach them to the robot if the hole patterns are different, and how to attach the motor coupler to the axle if it has a different diameter. We also need to consider if the new motor has a different amount of current or voltage needed, and if our H-Bridge can safely supply them without damaging itself.
Another risk we faced is that the robot’s chassis is limited to only supporting a load of 5-10kg (11-22lbs). This could be an issue since one of our use case requirements is that the cart can hold a maximum of 30 lbs. If needed, we will look into reinforcing the chassis, wheels, and axles to support more weight.
Design Changes & Justification
One major change we made was to use UWB instead of Bluetooth and GPS for shopper location tracking. Since iPhones already use UWB, and we plan on using an iPhone to host the mobile app, we decided to use UWB instead for more accurate indoor tracking and Apple’s Nearby Location framework. This adds another component to our project as we need to purchase a UWB module for the cart.
Another change we made was integrating the barcode scanner into our mobile app and removing the macro tracking. We wanted to better integrate the two functionalities of our project, the autonomous following and item tracking, and decided to move the barcode scanning to the phone to add more functionality to the mobile app. Additionally, we decided to remove the macro tracking since it did not provide a strong use case for our users. Since we will no longer need to buy a barcode scanner, this helps offset the cost of buying the UWB module.
There are no major changes to our schedule.
Product Solution Meeting Needs
A was written by Audrey, B was written by Elly, and C was written by Rose.
Part A: Public Health, Safety, and Welfare
Our solution meets the needs of users’ health and welfare by relieving stress on joints and back and lessening fatigue from pushing a heavy cart for a long time while grocery shopping. Instead, users can freely roam around the grocery store, and the robot will follow them. This also frees the hands of users, making shopping more accessible to those with disabilities, allowing elderly users with arthritis to avoid overextension, and allowing parents to shop while caring for children.
Our solution meets the needs of users’ safety by using LiDAR obstacle avoidance to prevent collisions with shelves, people, or other carts. Using the UWB module, the cart will follow the assigned user and not get confused in crowded spaces. Additionally, automatic stopping when the assigned user is outside of range will ensure the safety of bystanders.
Part B: Social Factors
Basket Buddy connects to social factors because it changes how people interact with grocery stores. By creating a simpler shopping experience where users no longer have to push the cart and have an easier way of keeping track of their items, Basket Buddy reduces the stress when grocery shopping, providing broader access to grocery shopping. This allows shoppers to focus on social interactions with other customers rather than worrying about keeping track of their shopping cart. The built-in barcode scanner and item tracking feature support economic decision-making, reflecting the social and cultural factors around budgeting and diet. Different groups of people may use this feature to manage their shopping finances and dietary restrictions. Additionally, the mobile app feature that allows users to generate a barcode totalling all the items in their cart creates a faster checkout process, with less time spent in lines. Features like obstacle avoidance also help reduce disruptions and conflicts in crowded aisles.
Part C: Economic Factors
Basket Buddy is designed to make use of readily available components. By using parts such as a Raspberry Pi, a Teensy microcontroller, and a UWB module, it avoids the expense of custom fabrication. This approach cuts down on one-time engineering work and helps the system move from prototype to store deployment faster, which ultimately lowers the cost per unit when the cart fleet is rolled out.
Day-to-day operating expenses are also minimal. The cart handles store navigation itself, and item tracking is done on the user’s device, so the cart system doesn ot depend on costly networking or cloud services, reducing recurring data and hosting fees. Its one-hour battery life is sized to match a typical shopping trip without overspending on oversized power systems. These choices mean retailers can introduce the carts without major increases to their operating budgets, while shoppers gain a more convenient and time-saving experience. Over time, that efficiency and the improved customer experience can boost store traffic and sales, making it a worthwhile investment.
