Project

# Title Team Members TA Documents Sponsor
14 AA/AAA Universal Charge/Discharger
 Aditya Prabhu
Jonathan Biel
Stan Hackman
 Jason Jung design_document1.pdf
design_document2.pdf
proposal1.pdf
proposal2.pdf
# Universal Battery Charge/Discharger

## Problem:
Batteries are a common and underestimated fire hazard in many homes, especially where a lack of knowledge meets convenience. A partially charged battery in a trash compactor could lead to devastating damage, large costs, and loss of life.

## Solution:
A battery discharger that rapidly discharges a battery for safe disposal by using variable paths to maximizes current flow within normal battery operating temperatures. The system would also, when directed by the user, charge LA or Lithium rechargeable batteries.

## System overview:
Our discharger would use variable resistance paths to adjust the level of discharge in order to maximize current for a given temperature. Rather than other types of battery discharger which seek to extend the life of the battery, the goal of ours would be to rapidly make a battery safe for disposal. The excess energy, then, would be dissipated as heat. When directed to, the system would also use a specialized IC to charge the battery using user input and dynamically monitoring system conditions

## Subsystems:

**Battery Receptacle** : Holds the battery and connects it to the system.
- Custom made battery trays which will allow the system to switch between AA & AAA battery usage.

**Cooling System** : A fan and heat sink for use in dissipating heat more effectively
- Motor part number : Tower Pro MG996 - needs 5-7VDC

**Temperature Monitoring System** : Monitors system and battery temperature for use by the control system
- Temperature probe part number : LM235Z - needs 5VDC

**Current and Battery Monitoring system** : Monitors battery charge and output current
- Current sensor : part number LAH 25-NP
- Voltage sensor on battery output :

**Charge System** : An IC designed to effectively charge LA and Lithium batteries.

**Discharge System** : Accepts inputs from the Control system to cycle through circuits in a current divider in order to maintain discharge rate and limit temperature buildup
- Custom PCB by us. It will function as a current divider, and will shift layout using IGBTs controlled by the Control System.

**Control System** : Accepts sensory data from the monitoring systems and alters the current paths and possibly fan speed
- An ATMEGA328 will serve as the microcontroller.

**User interface** : The User Interface subsystem will accept user input to determine the system’s mode of operation, and relay system conditions to the user.
- A switch in the casing to break the circuit on opening so that the battery can be safely removed and placed in.
- A switch on the outside of the casing to turn the whole system off.
- Two switches: charge/discharge and nickel/lithium
- LCD display depicting current charge/discharge status

**Power Supply** : Use a USB phone charger as a 5VDC input.
- Wall to USB adaptor 2YHA11B8018669


## Criterion For Success:

- Be able to rapidly (within an hour) deplete a battery from 50% charge to a condition it can be considered safe to common trash-borne hazards.
- Maintain temperature within safe battery limits to enable maximum sustained discharge rate without exceeding hazard thresholds (120F steady state, 140F transient).
- Be able to cycle active circuits based on system conditions to maximize discharge, minimize system temperature(as much as feasible to at least be safe), and maximize system’s operating lifetime.

## Extra Considerations:
- Every member will read the battery safety guidelines thoroughly, and review them at least monthly
- Each member will be certified with fire safety training and fire extinguisher training.


## NetIds:
- Stan Hackman (shackma2),
- Jonathan Biel (jbiel2),
- Aditya Prabhu (aprabhu3)

Decentralized Systems for Ground & Arial Vehicles (DSGAV)

Mingda Ma, Alvin Sun, Jialiang Zhang

Featured Project

# Team Members

* Yixiao Sun (yixiaos3)

* Mingda Ma (mingdam2)

* Jialiang Zhang (jz23)

# Problem Statement

Autonomous delivery over drone networks has become one of the new trends which can save a tremendous amount of labor. However, it is very difficult to scale things up due to the inefficiency of multi-rotors collaboration especially when they are carrying payload. In order to actually have it deployed in big cities, we could take advantage of the large ground vehicle network which already exists with rideshare companies like Uber and Lyft. The roof of an automobile has plenty of spaces to hold regular size packages with magnets, and the drone network can then optimize for flight time and efficiency while factoring in ground vehicle plans. While dramatically increasing delivery coverage and efficiency, such strategy raises a challenging problem of drone docking onto moving ground vehicles.

# Solution

We aim at tackling a particular component of this project given the scope and time limitation. We will implement a decentralized multi-agent control system that involves synchronizing a ground vehicle and a drone when in close proximity. Assumptions such as knowledge of vehicle states will be made, as this project is aiming towards a proof of concepts of a core challenge to this project. However, as we progress, we aim at lifting as many of those assumptions as possible. The infrastructure of the lab, drone and ground vehicle will be provided by our kind sponsor Professor Naira Hovakimyan. When the drone approaches the target and starts to have visuals on the ground vehicle, it will automatically send a docking request through an RF module. The RF receiver on the vehicle will then automatically turn on its assistant devices such as specific LED light patterns which aids motion synchronization between ground and areo vehicles. The ground vehicle will also periodically send out locally planned paths to the drone for it to predict the ground vehicle’s trajectory a couple of seconds into the future. This prediction can help the drone to stay within close proximity to the ground vehicle by optimizing with a reference trajectory.

### The hardware components include:

Provided by Research Platforms

* A drone

* A ground vehicle

* A camera

Developed by our team

* An LED based docking indicator

* RF communication modules (xbee)

* Onboard compute and communication microprocessor (STM32F4)

* Standalone power source for RF module and processor

# Required Circuit Design

We will integrate the power source, RF communication module and the LED tracking assistant together with our microcontroller within our PCB. The circuit will also automatically trigger the tracking assistant to facilitate its further operations. This special circuit is designed particularly to demonstrate the ability for the drone to precisely track and dock onto the ground vehicle.

# Criterion for Success -- Stages

1. When the ground vehicle is moving slowly in a straight line, the drone can autonomously take off from an arbitrary location and end up following it within close proximity.

2. Drones remains in close proximity when the ground vehicle is slowly turning (or navigating arbitrarily in slow speed)

3. Drone can dock autonomously onto the ground vehicle that is moving slowly in straight line

4. Drone can dock autonomously onto the ground vehicle that is slowly turning

5. Increase the speed of the ground vehicle and successfully perform tracking and / or docking

6. Drone can pick up packages while flying synchronously to the ground vehicle

We consider project completion on stage 3. The stages after that are considered advanced features depending on actual progress.

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