P14226: RC Camera Car
/public/Systems Design Subdirectory/

Systems Design

Table of Contents

Benchmarking & Feasibility

General

Dr. Cockburn also provided an article for the group to use as reference which was found in IEEE Control Systems Magazine in March of 2011.

IEEE Balancing Article

The article references a Youtube video that demonstates the desired long-term goal.

RC Car Balancing

Electronics

A variety of camera options were explored for this project. A detailed list of some of the models and their specs can be seen below.

Camera Benchmarking

Similarly, competitive microcontrollers on the market were analyzed for our project. A comparison can be seen below.

Microcontroller Benchmarking

Wireless communication systems were also considered for this project. A comparison of some major variants can be seen below.

Wireless Communication Benchmarking

Mechanical

The benchmarking done on the different chassis options available can be seen below.

Chassis Benchmarking

Data on the freescale ramp was analyzed, which should be a reasonable obstacle for the car. The equation for the travel is y = -x^2/81 + 4.

Freescale Cup Ramp

An algorithm was developed for the car that maps a course based on wheel revs and steering angle. This model assumes no slip.

Course Mapping

Functional Decomposition

Below are the functional decompositions done for this project. The three that were done are on a Systems-Level, Hardware-Level, and Software-Level.
System-Level

System-Level

The software and hardware-level functional decompositions were mapped to each other to make sure no functioality was left out in hardware.

Hardware-Level

Hardware-Level

Software-Level

Software-Level

Systems Architecture

The system architecture was also mapped out at a System-Level and at a Software Level.
System-Level

System-Level

Software-Level

Software-Level

Concept Generation

A morphological chart was created after targeting design drivers for our project. This can be seen below.

Morphological Chart

Based on our Morph chart, the following sketches of options have been developed for each area of the design.

Course Choices

Course Choices

Console

Console

Chassis and Microcontroller Mount

Chassis and Microcontroller Mount

Lap Time Measurement

Lap Time Measurement

From these options, concepts were selected based on brainstorming, benchmarking, and feasibility criteria.

Concept Selection

A Pugh Matrix was then created to weigh the concepts selected. The notes from this analysis can be seen on each chart.

Pugh Matrix

A final concept has not be specifically identified, as much is still open to change due to lack of budget information and sponsor feedback.

System Analysis

Mechanical

Rapid prototyping of a preliminary test platform was developed to allow the group to familiarize themselves with the different microcontrollers available. Set-by-step pictures were taken for documentation purposes, and a detailed assembly and modification instruction set are to be created using the images and information recorded in our logbooks. The provided chassis had the steering items mounted, suspension system and extra parts removed, and a adapter plate for the microcontrollers mounted on standoffs. An available Arduino Uno microcontroller, Arduino Motor Controller, Xbee Xplorer pair, and 3000 mAh LiPo Battery was interfaced with the chassis for testing purposes. Through some preliminary coding and program installation, the car was remotely moved using WASD controls. Much in the way of iterative design needs to do done to develop this into a marketable platform.
Preliminary Chassis

Preliminary Chassis

Modified Version

Modified Version

Check out the photo gallery for additional photos.

Photo Gallery

A preliminary testing video of the car moving can be seen below.

Testing 9-30-13

The adapter plate was created to strengthen the chassis and provide adequate room for mounting additional electronics. Additional holes were drilled to allow both the Arduino and Freedom boards to be mounted for testing. Based on our analysis of the Freescale Chassis, the following CAD model for the lexan adapter plate was made. This can be developed more through prototyping.

Adapter Plate

Due to preliminary testing with the car chassis with its low torque motors, we decided to look into the weight of the car. An analysis can be seen below.

Weight Test

A preliminary system model for the differential drive with PI control can be seen below, along with the system output.

Differential Drive Simulink

Differential Drive Simulink

Electrical

Based on the available information from benchmarking, a preliminary power budget was created for the RC car. This can be seen below.

RC Car Power Budget

Preliminary circuit Diagrams were also created for the RC car and console to keep track of data flow and wiring. These can be seen below.

RC Car Schematic

RC Car Schematic

Console Schematic

Console Schematic

General

Using the available information from all the analyses and benchmarking completed, a preliminary budget was drafted for the project. It can be seen below.

Total Budget

Risk Assessment

This is an early version of our Risk Assessment for the project, which will be updated with time.

Risk Assessment

A focus on major risks was condensed out of the detailed risk analysis. This is as follows.

Major Risks

Preliminary Test Plan

The test plan for the system has been updated with the current metrics and ways of testing them.

Test Plan 9-25-13