Requirements Specification

Background

There are many types of 2-dimensional vehicles out there, yet no generic method exists for controlling them through a single, consistent interface. Our design would create a common interface for all sorts of vehicles that can follow an arbitrary 2-dimensional path, such as cars, boats, tractors, and even lawnmowers or modern vacuum cleaners. Creating such a common interface will allow operators to be able to provide an arbitrary path of their choice and command any type of vehicle to follow that path, possibly with specific points along that path to carry out some action. Among the plethora of possibilities for such a design are: Planting crops (sowing seeds as an action to take regularly) Handicapped Assistance (picking up a newspaper at the front door) Water Based Vehicular Control (boats, robots, buoys) Patrolling Surveillance Camera.

The Deliverables

• A BC (BUNI Controlled) Toy Car:
• A fully programmed embedded microcontroller in the car.
• An implementation of the BUNI software on an HP iPaq1945, with java source code
• Overall block diagram of the system
• Schematic diagram of the hardware

Special Restrictions

• PDA software to be written in Java
• PDA software should be executable on other PDAs that have Bluetooth hardware, Java 2 Micro Edition (J2ME) Personal Profile and support for Java APIs for Bluetooth Wireless Technology (JABWT)

Principle of Operation

User will run the BUNI control software on their PDA. It will detect the car if it is within the maximum area. The user then chooses the method of control: Live or Draw. In Live mode, the user draws on the PDA's screen with the Stylus and the car responds in real-time. The faster the stylus is moved across the screen, the faster the car will go. In Draw mode, the user will draw a line on the screen with the stylus, and then press a Go button. The car will then do its best to trace the path that the user drew on the screen. In either method of control, the BUNI control software on the PDA will convert the movements of the stylus into a series of commands. These commands will then be sent via the Bluetooth link to the Bluetooth hardware and microcontroller mounted on the car. The microcontroller will then translate these commands into electrical signals that will be applied to the motor and steering system on the car.

User Interface

The user interface will be a Graphic User Interface that is a part of the BUNI control software on the PDA. The first piece of the GUI will display any BUNI devices in the area. The user selects one, and taps a connect button with the stylus. The selection between Line mode and Draw Mode can be accomplished with a pair of radio buttons. The 'drawing' area will have a grid on it, with each block scaled to a certain distance on the ground. For example, one block is 5 feet on the ground, and dragging the stylus the length of one block on the screen will move the car about 5 feet. The scale of the block will be able to be set by the user (possibly from a pre-determined list).

Input

The input to the overall system comes from the user moving the stylus over the PDA's touch-screen. The line drawn by the user is then fitted to a curve within the steering capabilities of the selected car. The shape of the line they draw and the speed with which the stylus moves are recorded.

Output

The output of the overall system will be signals sent to the motors and steering system of the car, which will cause it to move.

Acceptance Tests

Our design will aim at a 95% accuracy of following the path resolved from the input path, based on input scaling.