|ESTSS -> DEMO -> Embedded Systems -> LegoBot Controller|
|Click here to see our senior design presentation.|
|TA: Sueng-Yong Park
February 14, 1998
We propose to build a fully autonomous Legobot using a custom interface board with the 68HC12 microcontroller. Our design was influenced by a previous ECE 291 final project. While the 291 project focused on the programming aspect our project will focus on building the interface board and designing low power consumption hardware. The goal of our project is to have all of the sensors fully operational. We will build a small-scale demo robot to display some of the capabilities.
We will use the PWM features of the microcontroller to control an H-bridge power transistor configuration. Power MOSFET transistors will be used. The H-bridge will be controlling a higher power supply for the motors.
We will use the analog inputs of the microcontroller. The A/D converters will be used to acquire signals from the analog sensors. Tentative sensors are reflectance sensors, phototransistors, and potentiometers.
We will use the digital inputs of the microcontroller. DIP switches will be used for debugging, microswitches (bump sensors) will be used for obstacle detection enhancement, and infrared receivers will be used for infrared detection.
We will use the digital outputs on the microcontroller. A HEX display will be used for debugging and a directional pin is used for each motor.
Other Features of the Microcontroller
We will use the serial port RS232C to connect to the PC for debugging and downloading. The EEPROM will store the program for static code. We will take advantage of the HCMOS design to try and reduce power consumption from 5V to 3V.
|CPU Speed||8 MHz|
|Infrared Range||40 KHz|
|Debugging||Hex display - self run mode
Serial mode - development
|Feb 11-18||Become familiar with microcontroller and its features
Find hardware compatible devices
|Feb 18-25||Design for power and digital system outputs
Write code for testing purposes
Begin construction of hardware board
Formal Project Review
|Feb 25-Mar 4||Design of analog system
Write code for testing
|Mar 3- Mar 11||Finalize design
Debugging and development of demo model
|Mar 11-18||Catch up on anything needed|
|Mar 30 - Apr 8||Optimizing for low power consumption
|Apr 8-Apr 15||Debugging
Finish construction of demo model
|Motors||power MOSFET||Reflective object sensors|
|serial cable||Microswitches||batteries and harness|
|HEX display||heat shrink and tubing||connectors|