Driven Memory Screwdriver Antenna Controller 4. EVAULATION 4.1 Test Specification
Page 1 of 4
To insure that the controller will operate correctly, several tests must be performed on the individual components. The following procedures use a combination of hardware tests and software simulations to insure the required functionality. Even after passing the required tests, all the components must be brought together and tested as a complete unit. Figure 4.1 shows a block diagram of the antenna controller components. Each component must be tested to the specifications required in order for the antenna controller to operate correctly. The microcontroller is most important part of this controller. It determines the necessary action to take place depending upon input from the user interface. Movement of the antenna is controlled through a set of relays. As the antenna moves, the microcontroller detects pulse from the sensor mounted inside the antenna. The number of pulses translates to the number of inductor turns the antenna has moved. This number is then stored in memory for later retrieval.
Power
User Interface
Voltage Regulator
Microcontroller
Memory
Sensor Antenna
Relays
Figure 4.1 System Overview of the Antenna Controller In order to insure the antenna controller follows the set design constraints, certain pieces of equipment and software are needed. The following equipment and software are needed to verify the controller works within the specified constraints.
1. Digital multi-meter
2. 3. 4. 5. 6. 7. 4.2 Variable power supply Screwdriver antenna EZNEC software Antenna Analyzer Thermometer Heat gun
Test Specification Simulation
A simulation of the antenna will show the characteristics of the antenna when it is properly tuned. The antenna will be simulated using the EZNEC software package at three frequencies in the amateur radio spectrum. The frequencies chosen are the most commonly used in the HF spectrum. The results will show
ECE 4532: Senior Design I
October 14, 2004
Memory Driven Screwdriver Antenna Controller
Page 2 of 4
the radiation angle of the antenna and the 2:1 operating bandwidth. Since the controller will recall a position within two inductor turns, the simulation will show that the upper and lower bounds of the saved position will be within the range so that the lowest SWR is achieved. 4.3 Test Specification Hardware
Hardware testing will be performed on the on the controller based upon the design constraints. Testing will include verifying the voltage regulation, temperature, relay, and the LED display. Each of these components from the controller will be tested to insure they meet the specified design constraints. 4.3.1 Voltage Regulation
The microprocessor and other parts of the controller require a constant 5 volts to operate. The voltage regulation circuit will be required to maintain this voltage level regardless of the vehicle supply voltage, which will constantly change. Since the supply voltage from the vehicle can vary from 8 volts to as high as 16 volts, the voltage for the controller's power circuitry must be 5 volts and accurate to within 5%. Procedure: 1. Connect variable power supply to voltage regulator 2. Connect multi-meter to the output of voltage regulator 3. Turn on power supply and adjust to 8 volts output. 4. Measure output of regulator and insure it is between 4.75 5.25 volts. 5. Increase voltage in 0.5 steps and measure the output of the regulator. 6. With each increase, make sure the regulator output is between 4.75 5.25 volts. 4.3.2 Temperature
The components of the controller must operate properly in the extreme temperatures found in a vehicle. The tests will be conducted by exposing the controller to a maximum temperature of 80 C and a minimum of -40C. Procedure: 1. Connect controller circuit to power supply. 2. Using heat gun, heat controller circuitry to 80C, verify using an infrared thermometer. 3. Operate controller by moving antenna up and down. 4. Save and recall a position on the controller. 5. Verify correct operation of the controller. 6. Cool controller to -40C, verify using thermometer. 7. Operate controller manual adjustment. 8. Save and recall a position on the controller. 9. Verify correct operation of the controller. 4.3.4 Relay
The relay is required to pass five amps of current for one complete cycle of the antenna. One cycle is defined as completely extending the antenna to lowest frequency resonant and retracting the antenna to the highest resonant frequency. One complete cycle is approximately three minutes. The relay must also be activated from a five volt source providing a maximum of 25mA. Procedure: 1. Place multi-meter in current mode. 2. Connect variable power supply to control input of relay. 3. Connect 12 volt power supply to relay input.
ECE 4532: Senior Design I
October 14, 2004
Memory Driven Screwdriver Antenna Controller
Page 3 of 4
4. Connect a five amp load to relay output. 5. Turn on 12 volt power supply 6. Check to make sure the 5 amp load is off. 7. Turn on variable power supply and adjust to 5 volts. 8. Insure that the relay clicks, and the 5 amp load is on. 9. Check that the current to the relay control input is less than 25mA. 10. Monitor relay for three minutes and insure the load is fully operational 4.3.5 Display
Each of the seven segment LED displays will be tested for proper data output. The testing will be carried out by a program. This program will display numbers 0 through 9 with a one second delay between each number. This test will be incorporated into the controller software. Procedure: 1. Connect the display circuit to the PIC. 2. Load PIC with the test software. 3. Power up the test circuit. 4. Visually verify the output of each display as they cycle from 0 through 9. 4.4 Test Specification Software
Software testing will be done on the controller in conjunction with the antenna to insure that it operates accurately. The functional areas of the software testing will focus on antenna movement accuracy, read and write capabilities of memory, and reset functionality. By ensuring the correct operation of software implementation for these specific areas, the antenna controller will meet desired software design constraints. 4.4.1 Antenna Movement
Movement of the antenna will be accomplished with the microcontroller. When the manual up and down switches are depressed, the controller will activate the appropriate relay moving the antenna in the correct direction. When recalling a position, the controller will determine the direction to move the antenna based on the current position. Procedure: 1. Connect antenna and sensor to controller. 2. Set power supply to 12V and connect to controller. 3. Press up button, verify antenna moves up. 4. Press down button, verify antenna moves down. 5. Move antenna to any position, save position in memory button 1. 6. Use up/down button to move antenna to another position. 7. Press memory button 1 to recall position. 8. Verify antenna moves to the saved position. 9. Repeat steps 6 8 to for the remaining three buttons. 4.4.2 Memo...