Files
allwpilib/wpilibc/athena/include/Ultrasonic.h
Tyler Veness 0cd05d1a42 Cleaned up integer type usage in wpilibc (#92)
Replaced all unsigned types to signed and int32_t with int in wpilibc
2016-09-06 00:01:45 -07:00

98 lines
3.5 KiB
C++

/*----------------------------------------------------------------------------*/
/* Copyright (c) FIRST 2008-2016. All Rights Reserved. */
/* Open Source Software - may be modified and shared by FRC teams. The code */
/* must be accompanied by the FIRST BSD license file in the root directory of */
/* the project. */
/*----------------------------------------------------------------------------*/
#pragma once
#include <atomic>
#include <memory>
#include <set>
#include <string>
#include "Counter.h"
#include "LiveWindow/LiveWindowSendable.h"
#include "PIDSource.h"
#include "SensorBase.h"
#include "Task.h"
class DigitalInput;
class DigitalOutput;
/**
* Ultrasonic rangefinder class.
* The Ultrasonic rangefinder measures absolute distance based on the round-trip
* time of a ping generated by the controller. These sensors use two
* transducers, a speaker and a microphone both tuned to the ultrasonic range. A
* common ultrasonic sensor, the Daventech SRF04 requires a short pulse to be
* generated on a digital channel. This causes the chirp to be emitted. A second
* line becomes high as the ping is transmitted and goes low when the echo is
* received. The time that the line is high determines the round trip distance
* (time of flight).
*/
class Ultrasonic : public SensorBase,
public PIDSource,
public LiveWindowSendable {
public:
enum DistanceUnit { kInches = 0, kMilliMeters = 1 };
Ultrasonic(DigitalOutput* pingChannel, DigitalInput* echoChannel,
DistanceUnit units = kInches);
Ultrasonic(DigitalOutput& pingChannel, DigitalInput& echoChannel,
DistanceUnit units = kInches);
Ultrasonic(std::shared_ptr<DigitalOutput> pingChannel,
std::shared_ptr<DigitalInput> echoChannel,
DistanceUnit units = kInches);
Ultrasonic(int pingChannel, int echoChannel, DistanceUnit units = kInches);
virtual ~Ultrasonic();
void Ping();
bool IsRangeValid() const;
static void SetAutomaticMode(bool enabling);
double GetRangeInches() const;
double GetRangeMM() const;
bool IsEnabled() const { return m_enabled; }
void SetEnabled(bool enable) { m_enabled = enable; }
double PIDGet() override;
void SetPIDSourceType(PIDSourceType pidSource) override;
void SetDistanceUnits(DistanceUnit units);
DistanceUnit GetDistanceUnits() const;
void UpdateTable() override;
void StartLiveWindowMode() override;
void StopLiveWindowMode() override;
std::string GetSmartDashboardType() const override;
void InitTable(std::shared_ptr<ITable> subTable) override;
std::shared_ptr<ITable> GetTable() const override;
private:
void Initialize();
static void UltrasonicChecker();
// Time (sec) for the ping trigger pulse.
static constexpr double kPingTime = 10 * 1e-6;
// Priority that the ultrasonic round robin task runs.
static const int kPriority = 64;
// Max time (ms) between readings.
static constexpr double kMaxUltrasonicTime = 0.1;
static constexpr double kSpeedOfSoundInchesPerSec = 1130.0 * 12.0;
static Task m_task; // task doing the round-robin automatic sensing
static std::set<Ultrasonic*> m_sensors; // ultrasonic sensors
static std::atomic<bool> m_automaticEnabled; // automatic round robin mode
std::shared_ptr<DigitalOutput> m_pingChannel;
std::shared_ptr<DigitalInput> m_echoChannel;
bool m_enabled = false;
Counter m_counter;
DistanceUnit m_units;
std::shared_ptr<ITable> m_table;
};