This class abstracts the communication with the sensors measuring the state of the swingjoints. More...

#include <hall_sensor.h>

Public Member Functions
	HallSensor (const std::string &spi_device, uint8_t spi_cs_id, uint8_t spi_mode, uint8_t spi_bits, uint32_t spi_speed, uint16_t spi_delay, double zero_point, uint16_t mux_sel_pin_1, uint16_t mux_sel_pin_2)
	Constructor of the HallSensor class. More...

double	getValue ()
	Reads the Angle of the HallSensor. More...

void	setZeroPoint ()
	Sets the next Angle sent from the Sensor as the new zero_point_ for the angles.

uint8_t	getErrors ()
	Returns errors of last read. More...

Detailed Description

This class abstracts the communication with the sensors measuring the state of the swingjoints.

The left and right swingsensor, measure the position the swingjoints. They are implemented using As5047D Hall Sensors as well as magnets attached to the output lever of the motor assembly (pictured below).

The magnets are affixed using 3d printed caps, which offer no way to predetermine the magnetic field at a given angle. This means that the sensor output which is initially in counts has to be calibrated. This is done either during initialization using the zero_point value or during runtime using the setZeroPoint method.

After initialization the sensors produce values in the range of [-pi,pi]. A angle of zero is specified as the angle at which the position of the output lever is perpendicular to the two mounting brackets of the hall sensor Because these mounting brackets constrict the movement output lever the actually achievable range of motion is [-pi/2,pi/2].

The embedded communication with the Sensor is done via SPI according to their datasheet. The connection of the sensor to the beaglebone can be seen in the wiring diagram.

Constructor & Destructor Documentation

◆ HallSensor()

HallSensor::HallSensor	(	const std::string &	spi_device,
		uint8_t	spi_cs_id,
		uint8_t	spi_mode,
		uint8_t	spi_bits,
		uint32_t	spi_speed,
		uint16_t	spi_delay,
		double	zero_point,
		uint16_t	mux_sel_pin_1,
		uint16_t	mux_sel_pin_2
	)

Constructor of the HallSensor class.

Parameters

SPI	device, Chip select ID, mode, number of bits, communication speed and delay as well as the angle which is considered zero by the kinematics, also the selector pins for the multiplexer.

Member Function Documentation

◆ getErrors()

uint8_t HallSensor::getErrors ( )

Returns errors of last read.

This function reads and clears the error variable, containing the flags for different error types of the sensor. It should be called after a getValue() call.

◆ getValue()

double HallSensor::getValue ( )

Reads the Angle of the HallSensor.

This function returns a double containing the current Angle of the joint according to the angle specifications above.

The documentation for this class was generated from the following files: