Difference between revisions of "Components Previously on the PCB"
Line 38: | Line 38: | ||
|} | |} | ||
The Watchdog and associated hardware were removed because an unsuccessful loop execution by the DUE was deemed to be an unlikely source of failure. | The Watchdog and associated hardware were removed because an unsuccessful loop execution by the DUE was deemed to be an unlikely source of failure. | ||
+ | |||
+ | ===POT=== | ||
+ | The POT (Potentiometer) pin-outs is a grouping of pin-out ports that were designed to be used to connect a potentiometer. A potentiometer is an adjustable resistor that provides varying voltages. By keeping the current constant, measuring how much the potentiometer was adjusted allows one to know the voltage. When making the bike, it was debated whether using a potentiometer or an encoder was better for measuring the position of the bike's front wheel. Although the potentiometer is more accurate than the encoder, it was decided that an encoder was to be used because it was easier to work with. Thus, the POT pin-out ports were deemed to be unecessary. | ||
+ | {| class="wikitable" | ||
+ | |- | ||
+ | ! Pin Label | ||
+ | ! Connected To | ||
+ | |- | ||
+ | | 1 | ||
+ | | GND | ||
+ | |- | ||
+ | | 2 | ||
+ | | DUE Pin A10 | ||
+ | |- | ||
+ | | 3 | ||
+ | | 3.3 V | ||
+ | |} | ||
+ | |||
===Additional Components Only Used by CUSail=== | ===Additional Components Only Used by CUSail=== | ||
Line 50: | Line 68: | ||
==Other Components== | ==Other Components== | ||
− | |||
===IMU & RS=== | ===IMU & RS=== | ||
The IMU (Inertial Measurement Unit) is a sensor used to provide information regarding the bike's current angle and angular rates. The IMU is connected to the board using a six pin-out terminal (figure N). Because the IMU communicates with the DUE using [[Fundamental_Concepts|SPI]], the pin-out terminal requires MISO, MOSI, and SCK connections to the DUE. The pin-out terminal has a pin called IMU-CS and it is believed to be the designated SS (Slave Select) for the IMU. Additionally, two pins (5V and GND) supplies power to the IMU. | The IMU (Inertial Measurement Unit) is a sensor used to provide information regarding the bike's current angle and angular rates. The IMU is connected to the board using a six pin-out terminal (figure N). Because the IMU communicates with the DUE using [[Fundamental_Concepts|SPI]], the pin-out terminal requires MISO, MOSI, and SCK connections to the DUE. The pin-out terminal has a pin called IMU-CS and it is believed to be the designated SS (Slave Select) for the IMU. Additionally, two pins (5V and GND) supplies power to the IMU. |
Revision as of 13:26, 26 April 2020
The printed circuit board has many components that have been deemed obsolete and removed. Below is a list of those components, how they worked, and why the were removed.
Contents
Components Removed In Spring 2020
Prior to spring 2020, the PCB was designed for use by both CUBike and CUSail, resulting in many parts that were not necessary for the functioning of the bike. In Spring 2020, a major overhaul was started in part to remove many of these unnecessary parts.
Watchdog
The Watchdog is an external timer circuit that assured the Arduino DUE was correctly executing its loop. The Watchdog’s timer was reset each time the DUE successfully completed a loop. However, if the DUE’s loop execution was unsuccessful, the Watchdog’s timer would not be reset, causing an emergency shutdown and preventing damage to the bike’s systems.
The Watchdog connected to the PCB through three pins, labeled WD+DPINS, and an op-amp.
WD+DPINS
Pin Label | Connected To |
---|---|
1 | DUE pin 45 |
2 | DUE pin 43 |
3 | Op-Amp pin 1 WDO |
Associated Op-Amp
Pin Label | Connected To |
---|---|
1 WDO | WD+DPINS pin 3 |
2 GND | GND |
3 EN | DUE pin 41 |
4 WDI | DUE pin 42 |
5 VCC | C35 --> GND |
The Watchdog and associated hardware were removed because an unsuccessful loop execution by the DUE was deemed to be an unlikely source of failure.
POT
The POT (Potentiometer) pin-outs is a grouping of pin-out ports that were designed to be used to connect a potentiometer. A potentiometer is an adjustable resistor that provides varying voltages. By keeping the current constant, measuring how much the potentiometer was adjusted allows one to know the voltage. When making the bike, it was debated whether using a potentiometer or an encoder was better for measuring the position of the bike's front wheel. Although the potentiometer is more accurate than the encoder, it was decided that an encoder was to be used because it was easier to work with. Thus, the POT pin-out ports were deemed to be unecessary.
Pin Label | Connected To |
---|---|
1 | GND |
2 | DUE Pin A10 |
3 | 3.3 V |
Additional Components Only Used by CUSail
Sail Motor
The old PCB contained outputs for the sail motor and bike motor. Since the bike is not a sailboat, the sail motor outputs were removed.
Sail Power
Similar to the sail motor, only the bike power output is necessary.
H-Bridges
Xbee Pro
The Xbee Pro was used in conjunction with CUSail's remote controller. The bike uses a different controller.
Other Components
IMU & RS
The IMU (Inertial Measurement Unit) is a sensor used to provide information regarding the bike's current angle and angular rates. The IMU is connected to the board using a six pin-out terminal (figure N). Because the IMU communicates with the DUE using SPI, the pin-out terminal requires MISO, MOSI, and SCK connections to the DUE. The pin-out terminal has a pin called IMU-CS and it is believed to be the designated SS (Slave Select) for the IMU. Additionally, two pins (5V and GND) supplies power to the IMU.
IMU Pin-Out | Terminal Connection |
---|---|
MISO | MISO |
MOSI | MOSI |
SCK | SCK |
IMU-CS | A11 |
3.3 V | 3.3 V |
GND | GND |
Similarly, the RS communicates to the DUE using SPI and thus requires the same terminals, MISO, MOSI, SCK, and (in this case) RS-CS. The RS is connected to the board through a six pin-out terminal, two terminals being GND and 3.3V. Initially, the RS terminal was used for the BeagleBone Black that is a micro-controller. The motivation behind the BeagleBone was that the DUE would communicate with the IMU through the BeagleBone. However, the BeagleBone is no longer used and the DUE directly communicates with the IMU directly via SPI. Currently, the pin-put terminal for RS is not used but serves as an extra SPI communication port and thus may be used for any future microcontrollers or peripherals (e.g. Raspberry Pi).
RS Pin-Out | Terminal Connection |
---|---|
MISO | MISO |
MOSI | MOSI |
SCK | SCK |
IMU-CS | Pin 52 |
3.3 V | 3.3 V |
GND | GND |
Design Changes for IMU & RS
Because the IMU is a critical component for developing an autonomous bicycle and is a sensor that needs to be read periodically and requires initialization, the current implementation of the IMU is going to be remained unchanged. Since the RS terminal is not being used but can be useful for any future implementation of micro-controllers or peripherals that require SPI, the RS pin-out terminal is also remain unchanged.