Project

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

Autonomous Sailboat

Riley Baker, Arthur Liang, Lorenzo Rodriguez Perez

Autonomous Sailboat

Featured Project

# Autonomous Sailboat

Team Members:

- Riley Baker (rileymb3)

- Lorenzo Pérez (lr12)

- Arthur Liang (chianl2)

# Problem

WRSC (World Robotic Sailing Championship) is an autonomous sailing competition that aims at stimulating the development of autonomous marine robotics. In order to make autonomous sailing more accessible, some scholars have created a generic educational design. However, these models utilize expensive and scarce autopilot systems such as the Pixhawk Flight controller.

# Solution

The goal of this project is to make an affordable, user- friendly RC sailboat that can be used as a means of learning autonomous sailing on a smaller scale. The Autonomous Sailboat will have dual mode capability, allowing the operator to switch from manual to autonomous mode where the boat will maintain its current compass heading. The boat will transmit its sensor data back to base where the operator can use it to better the autonomous mode capability and keep track of the boat’s position in the water. Amateur sailors will benefit from the “return to base” functionality provided by the autonomous system.

# Solution Components

## On-board

### Sensors

Pixhawk - Connect GPS and compass sensors to microcontroller that allows for a stable state system within the autonomous mode. A shaft decoder that serves as a wind vane sensor that we plan to attach to the head of the mast to detect wind direction and speed. A compass/accelerometer sensor and GPS to detect the position of the boat and direction of travel.

### Actuators

2 servos - one winch servo that controls the orientation of the mainsail and one that controls that orientation of the rudder

### Communication devices

5 channel 2.4 GHz receiver - A receiver that will be used to select autonomous or manual mode and will trigger orders when in manual mode.

5 channel 2.4 GHz transmitter - A transmitter that will have the ability to switch between autonomous and manual mode. It will also transfer servos movements when in manual mode.

### Power

LiPo battery

## Ground control

Microcontroller - A microcontroller that records sensor output and servo settings for radio control and autonomous modes. Software on microcontroller processes the sensor input and determines the optimum rudder and sail winch servo settings needed to maintain a prescribed course for the given wind direction.

# Criterion For Success

1. Implement dual mode capability

2. Boat can maintain a given compass heading after being switched to autonomous mode and incorporates a “return to base” feature that returns the sailboat back to its starting position

3. Boat can record and transmit servo, sensor, and position data back to base

Project Videos