Project

# Title Team Members TA Documents Sponsor
79 SUPERCAPACITOR MODULE FOR ILLINI-ROBOMASTER ROBOT
Haoyuan You
Shaurya Grover
Matthew Qi design_document2.pdf
final_paper1.pdf
photo1.jpg
photo2.jpg
presentation1.pptx
proposal1.pdf
SUPERCAPACITOR MODULE FOR ILLINI-ROBOMASTER ROBOT

Team Members:

- You, Haoyuan (hy19)
- Grover, Shaurya (sgrover4)

PROBLEM

Illini-Robomaster (iRM) is an RSO at UIUC competing in the Robomaster robotics competition. During a match, robots will be punished when exceeding the power limit (80W), but the monitoring system (referee system) is only checking the power output from the battery. To maximize available power for the motors and achieve greater mobility, we need a device to store and release energy. Existing solutions are either prohibited by the competition rules, too large to fit in our mobile robot, or sold at an unacceptable price by our competitor universities.

SOLUTION

We propose a supercapacitor module to supply power in addition to the battery. It should be capable to store energy from the battery when the robot is running on low power and release energy when the robot needs it. Thus, we have more power available. The supercapacitor module should be controlled by the master MCU on the robot and when additional power is needed, the master MCU can control the MCU on the module to release the power.

We propose two solutions:

1. The capacitor sits between the battery and the rest of the robot’s power bus. The robot is powered entirely by the capacitor and the battery only charges the capacitor. The battery, capacitor, and the robot’s power bus are interconnected with DC-DC converters.
Battery = DC-DC = Capacitor = DC-DC = Motors (Robot)

“=” stands for power connection

2. The battery directly connects to the power bus and the capacitor is connected to the power bus with a bi-directional DC-DC converter. DC-DC converter charges the capacitor when the battery has extra power and reverts the direction of current when the robot needs extra power. We think this is a similar case to a redundant power supply design.
Battery = Motors (Robot) = DC-DC (Bidirectional) = Capacitor

“=” stands for power connection

We think there are advantages to the second design due to one more DC-DC in the first design introduces extra power loss. Moreover, if the capacitor module breaks in the second design the rest of the robot is left unaffected. Yet we also think the second design is more challenging to implement.

SOLUTION COMPONENTS

CONTROL UNIT (SAME FOR BOTH DESIGNS)

MCU
Control the Power unit and communicate with the master MCU on the robot through CAN or UART. Either Atmega328 or STM32F103 depending on prototype performance.

Voltage and current sensor
Measure the voltage and current of the capacitor to estimate the power output and report to the master MCU

POWER UNIT

Capacitor array (Same for both designs)
The game rule restricts the maximum energy storage to be 2000J and the max voltage on the power bus is 30V, so the max capacitance is around 4.4F. We might choose a smaller value for safety concerns. There is also an unused capacitor array in the RSO, we might consider integrating it into the module to reduce cost.

Design 1: {

Supercapacitor charging control module
Charging of the capacitor from the battery, controlled by the MCU. This might be a DC-DC converter or off-the-shelf capacitor charging control module (like BQ24640)

DC-DC module
Convert the output voltage to the same voltage as the power bus (24V). Consider using a buck-boost converter.

}

Design 2: {

Bi-directional DC-DC converter
Convert the voltage from the power bus to the capacitor during charging and convert the capacitor's voltage to the power bus's during discharging. Controlled by the MCU to switch between two directions.

}

INTERFACES ON THE TARGETING ROBOT

These are not part of the module but will be integrated with the module during the competition this June:

24V M3508 motors and C620 motor speed controllers.

24V battery

The module should be able to sustain the induced current from the motors and not break any device powered by it.

CRITERION FOR SUCCESS

- Criterion 1: The supercapacitor module must be able to store a certain amount of energy
- Criterion 2: The supercapacitor module must be able to release energy
- Criterion 3: The supercapacitor module can be controlled by the master MCU

Modularized Electronic Locker

Jack Davis, Joshua Nolan, Jake Pu

Modularized Electronic Locker

Featured Project

Group Member: Jianhao (Jake) Pu [jpu3], Joshua Nolan [jtnolan2], John (Jack) Davis [johnhd4]

Problem:

Students living off campus without a packaging station are affected by stolen packages all the time. As a result of privacy concerns and inconsistent deployment, public cameras in Champaign and around the world cannot always be relied upon. Therefore, it can be very difficult for victims to gather evidence for a police report. Most of the time, the value of stolen items is small and they are usually compensated by the sellers (Amazon and Apple are very understanding). However, not all deliveries are insured and many people are suffering from stolen food deliveries during the COVID-19 crisis. We need a low-cost solution that can protect deliveries from all vendors.

Solution Overview:

Our solution is similar to Amazon Hub Apartment Locker and Luxer One. Like these services, our product will securely enclose the package until the owners claim the contents inside. The owner of the contents can claim it using a phone number or a unique user identification code generated and managed by a cloud service.

The first difference we want to make from these competitors is cost. According to an article, the cost of a single locker is from $6000 - $20000. We want to minimize such costs so that we can replace the traditional mailbox. We talked to a Chinese manufacturer and got a hardware quote of $3000. We can squeeze this cost if we just design our own control module on ESP32 microcontrollers.

The second difference we want to make is modularity. We will have a sensor module, a control module, a power module and any number of storage units for hardware. We want to make standardized storage units that can be stacked into any configuration, and these storage units can be connected to a control module through a communication bus. The control module houses the hardware to open or close all of the individual lockers. A household can purchase a single locker and a control module just for one family while apartment buildings can stack them into the lockers we see at Amazon Hub. I think the hardware connection will be a challenge but it will be very effective at lowering the cost once we can massively manufacture these unit lockers.

Solution Components:

Storage Unit

Basic units that provide a locker feature. Each storage unit will have a cheap microcontroller to work as a slave on the communication bus and control its electronic lock (12V 36W). It has four connectors on top, bottom, left, and right sides for stackable configuration.

Control Unit

Should have the same dimension as one of the storage units so that it could be stacked with them. Houses ESP32 microcontroller to run control logics on all storage units and uses the built-in WiFi to upload data to a cloud server. If sensor units are detected, it should activate more security features accordingly.

Power Unit

Power from the wall or from a backup battery power supply and the associated controls to deliver power to the system. Able to sustain high current in a short time (36W for each electronic lock). It should also have protection against overvoltage and overcurrent.

Sensor Modules

Sensors such as cameras, motion sensors, and gyroscopes will parlay any scandalous activities to the control unit and will be able to capture a photo to report to authorities. Sensors will also have modularity for increased security capabilities.

Cloud Support

Runs a database that keeps user identification information and the security images. Pushes notification to end-users.

Criterion for Success:

Deliverers (Fedex, Amazon, Uber Eats, etc.) are able to open the locker using a touchscreen and a use- provided code to place their package inside. Once the package is inside of the locker, a message will be sent to the locker owner that their delivery has arrived. Locker owners are able to open the locker using a touchscreen interface. Owners are also able to change the passcode at any time for security reasons. The locker must be difficult to break into and offer theft protection after multiple incorrect password attempts.

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