PWM automatic trigger system (ATS) for parachutes (#13726)

* parameter and logic to commander for triggering failsafe from external automatic trigger system.
* logic to startup script for enabling ATS. Added uORB publishing to pwm_input module.
* Refactored out CDev usage from pwm_input and ll40ls. Refactored out ll40ls specifics from pwm_input and cleaned up dead code.

ROMFS/px4fmu_common/init.d/rc.sensors

@@ -58,6 +58,12 @@ then
 	fi
 fi
 
+# External automatic trigger system
+if param compare FD_EXT_ATS_EN 1
+then
+	pwm_input start
+fi
+
 # Lidar-Lite on I2C
 if param compare -s SENS_EN_LL40LS 2
 then

ROMFS/px4fmu_common/init.d/rcS

@@ -360,6 +360,15 @@ else
 		set AUX_MODE pwm4
 	fi
 
+
+	# Check if ATS is enabled
+	if param compare FD_EXT_ATS_EN 1
+	then
+		# Clear pins 5 and 6.
+		set FMU_MODE pwm4
+		set AUX_MODE pwm4
+	fi
+
 	if param greater TRIG_MODE 0
 	then
 		# We ONLY support trigger on pins 5 and 6 when simultanously using AUX for actuator output.

msg/pwm_input.msg

@@ -1,4 +1,4 @@
-uint64 timestamp	# time since system start (microseconds)
+uint64 timestamp	# Time since system start (microseconds)
-uint64 error_count
+uint64 error_count	# Timer overcapture error flag (AUX5 or MAIN5)
 uint32 pulse_width	# Pulse width, timer counts
 uint32 period		# Period, timer counts

msg/vehicle_status.msg

@@ -15,6 +15,7 @@ uint8 FAILURE_NONE = 0
 uint8 FAILURE_ROLL = 1 	# (1 << 0)
 uint8 FAILURE_PITCH = 2	# (1 << 1)
 uint8 FAILURE_ALT = 4 	# (1 << 2)
+uint8 FAILURE_EXT = 8 	# (1 << 3)
 
 # HIL
 uint8 HIL_STATE_OFF = 0

src/drivers/distance_sensor/ll40ls/LidarLitePWM.cpp

@@ -44,10 +44,13 @@
 
 #include "LidarLitePWM.h"
 
+#ifdef LIDAR_LITE_PWM_SUPPORTED
+
 LidarLitePWM::LidarLitePWM(const uint8_t rotation) :
 	LidarLite(rotation),
 	ScheduledWorkItem(MODULE_NAME, px4::wq_configurations::hp_default)
 {
+	px4_arch_configgpio(GPIO_VDD_RANGEFINDER_EN);
 }
 
 LidarLitePWM::~LidarLitePWM()
@@ -113,17 +116,16 @@ LidarLitePWM::measure()
 int
 LidarLitePWM::collect()
 {
-	int fd = ::open(PWMIN0_DEVICE_PATH, O_RDONLY);
+	pwm_input_s pwm_input;
 
-	if (fd == -1) {
+	if (_sub_pwm_input.update(&pwm_input)) {
-		return PX4_ERROR;
+
-	}
+		_pwm = pwm_input;
 
-	if (::read(fd, &_pwm, sizeof(_pwm)) == sizeof(_pwm)) {
-		::close(fd);
 		return PX4_OK;
 	}
 
-	::close(fd);
 	return EAGAIN;
 }
+
+#endif

src/drivers/distance_sensor/ll40ls/LidarLitePWM.h

@@ -45,14 +45,15 @@
 
 #include "LidarLite.h"
 
-#include <stdio.h>
-#include <string.h>
-
-#include <drivers/drv_hrt.h>
-#include <drivers/drv_pwm_input.h>
-#include <px4_platform_common/defines.h>
 #include <px4_platform_common/px4_work_queue/ScheduledWorkItem.hpp>
+
 #include <uORB/topics/pwm_input.h>
+#include <uORB/Subscription.hpp>
+
+#ifdef GPIO_GPIO5_OUTPUT
+
+#define LIDAR_LITE_PWM_SUPPORTED
+#define GPIO_VDD_RANGEFINDER_EN GPIO_GPIO5_OUTPUT
 
 class LidarLitePWM : public LidarLite, public px4::ScheduledWorkItem
 {
@@ -73,7 +74,9 @@ protected:
 
 private:
 
-	int _pwmSub{-1};
+	uORB::Subscription _sub_pwm_input{ORB_ID(pwm_input)};
 
 	pwm_input_s _pwm{};
 };
+
+#endif

src/drivers/distance_sensor/ll40ls/ll40ls.cpp

@@ -164,7 +164,12 @@ start_pwm(const uint8_t rotation)
 		return PX4_OK;
 	}
 
+#ifdef LIDAR_LITE_PWM_SUPPORTED
 	instance = new LidarLitePWM(rotation);
+#else
+	instance = nullptr;
+	PX4_ERR("PWM input not supported.");
+#endif
 
 	if (instance == nullptr) {
 		PX4_ERR("Failed to instantiate the driver");

src/drivers/drv_pwm_input.h

@@ -1,51 +0,0 @@
-/****************************************************************************
- *
- *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in
- *    the documentation and/or other materials provided with the
- *    distribution.
- * 3. Neither the name PX4 nor the names of its contributors may be
- *    used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
- * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- ****************************************************************************/
-
-#pragma once
-
-#include <sys/types.h>
-#include <stdbool.h>
-
-#include <time.h>
-#include <queue.h>
-
-#define PWMIN0_DEVICE_PATH		"/dev/pwmin0"
-
-__BEGIN_DECLS
-
-/*
- * Initialise the timer
- */
-__EXPORT extern int	pwm_input_main(int argc, char *argv[]);
-
-__END_DECLS

src/drivers/pwm_input/pwm_input.h

@@ -0,0 +1,151 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2019 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+#include <drivers/drv_hrt.h>
+#include <drivers/device/device.h>
+
+#include <px4_platform_common/module.h>
+
+#include <uORB/uORB.h>
+#include <uORB/Publication.hpp>
+#include <uORB/topics/pwm_input.h>
+
+#if HRT_TIMER == PWMIN_TIMER
+#error cannot share timer between HRT and PWMIN
+#endif
+
+#if !defined(GPIO_PWM_IN) || !defined(PWMIN_TIMER) || !defined(PWMIN_TIMER_CHANNEL)
+#error PWMIN defines are needed in board_config.h for this board
+#endif
+
+/* Get the timer defines */
+#define INPUT_TIMER PWMIN_TIMER
+#include "timer_registers.h"
+#define PWMIN_TIMER_BASE	TIMER_BASE
+#define PWMIN_TIMER_CLOCK	TIMER_CLOCK
+#define PWMIN_TIMER_POWER_REG	TIMER_CLOCK_POWER_REG
+#define PWMIN_TIMER_POWER_BIT	TIMER_CLOCK_POWER_BIT
+#define PWMIN_TIMER_VECTOR	TIMER_IRQ_REG
+
+/*
+ * HRT clock must be at least 1MHz
+ */
+#if PWMIN_TIMER_CLOCK <= 1000000
+# error PWMIN_TIMER_CLOCK must be greater than 1MHz
+#endif
+
+/*
+ * Timer register accessors
+ */
+#define REG(_reg)	(*(volatile uint32_t *)(PWMIN_TIMER_BASE + _reg))
+
+#define rCR1		REG(STM32_GTIM_CR1_OFFSET)
+#define rCR2		REG(STM32_GTIM_CR2_OFFSET)
+#define rSMCR		REG(STM32_GTIM_SMCR_OFFSET)
+#define rDIER		REG(STM32_GTIM_DIER_OFFSET)
+#define rSR		REG(STM32_GTIM_SR_OFFSET)
+#define rEGR		REG(STM32_GTIM_EGR_OFFSET)
+#define rCCMR1		REG(STM32_GTIM_CCMR1_OFFSET)
+#define rCCMR2		REG(STM32_GTIM_CCMR2_OFFSET)
+#define rCCER		REG(STM32_GTIM_CCER_OFFSET)
+#define rCNT		REG(STM32_GTIM_CNT_OFFSET)
+#define rPSC		REG(STM32_GTIM_PSC_OFFSET)
+#define rARR		REG(STM32_GTIM_ARR_OFFSET)
+#define rCCR1		REG(STM32_GTIM_CCR1_OFFSET)
+#define rCCR2		REG(STM32_GTIM_CCR2_OFFSET)
+#define rCCR3		REG(STM32_GTIM_CCR3_OFFSET)
+#define rCCR4		REG(STM32_GTIM_CCR4_OFFSET)
+#define rDCR		REG(STM32_GTIM_DCR_OFFSET)
+#define rDMAR		REG(STM32_GTIM_DMAR_OFFSET)
+
+/*
+ * Specific registers and bits used by HRT sub-functions
+ */
+#if PWMIN_TIMER_CHANNEL == 1
+#define rCCR_PWMIN_A		rCCR1			/* compare register for PWMIN */
+#define DIER_PWMIN_A		(GTIM_DIER_CC1IE) 	/* interrupt enable for PWMIN */
+#define SR_INT_PWMIN_A		GTIM_SR_CC1IF		/* interrupt status for PWMIN */
+#define rCCR_PWMIN_B		rCCR2 			/* compare register for PWMIN */
+#define SR_INT_PWMIN_B		GTIM_SR_CC2IF		/* interrupt status for PWMIN */
+#define CCMR1_PWMIN		((0x02 << GTIM_CCMR1_CC2S_SHIFT) | (0x01 << GTIM_CCMR1_CC1S_SHIFT))
+#define CCMR2_PWMIN		0
+#define CCER_PWMIN		(GTIM_CCER_CC2P | GTIM_CCER_CC1E | GTIM_CCER_CC2E)
+#define SR_OVF_PWMIN		(GTIM_SR_CC1OF | GTIM_SR_CC2OF)
+#define SMCR_PWMIN_1		(0x05 << GTIM_SMCR_TS_SHIFT)
+#define SMCR_PWMIN_2		((0x04 << GTIM_SMCR_SMS_SHIFT) | SMCR_PWMIN_1)
+#elif PWMIN_TIMER_CHANNEL == 2
+#define rCCR_PWMIN_A		rCCR2			/* compare register for PWMIN */
+#define DIER_PWMIN_A		(GTIM_DIER_CC2IE)	/* interrupt enable for PWMIN */
+#define SR_INT_PWMIN_A		GTIM_SR_CC2IF		/* interrupt status for PWMIN */
+#define rCCR_PWMIN_B		rCCR1			/* compare register for PWMIN */
+#define DIER_PWMIN_B		GTIM_DIER_CC1IE		/* interrupt enable for PWMIN */
+#define SR_INT_PWMIN_B		GTIM_SR_CC1IF		/* interrupt status for PWMIN */
+#define CCMR1_PWMIN		((0x01 << GTIM_CCMR1_CC2S_SHIFT) | (0x02 << GTIM_CCMR1_CC1S_SHIFT))
+#define CCMR2_PWMIN		0
+#define CCER_PWMIN		(GTIM_CCER_CC1P | GTIM_CCER_CC1E | GTIM_CCER_CC2E)
+#define SR_OVF_PWMIN		(GTIM_SR_CC1OF | GTIM_SR_CC2OF)
+#define SMCR_PWMIN_1		(0x06 << GTIM_SMCR_TS_SHIFT)
+#define SMCR_PWMIN_2		((0x04 << GTIM_SMCR_SMS_SHIFT) | SMCR_PWMIN_1)
+#else
+#error PWMIN_TIMER_CHANNEL must be either 1 and 2.
+#endif
+
+class PWMIN : public ModuleBase<PWMIN>
+{
+public:
+	void start();
+	void publish(uint16_t status, uint32_t period, uint32_t pulse_width);
+	void print_info(void);
+
+	static int pwmin_tim_isr(int irq, void *context, void *arg);
+
+	static int custom_command(int argc, char *argv[]);
+	static int print_usage(const char *reason = nullptr);
+	static int task_spawn(int argc, char *argv[]);
+
+
+private:
+	void timer_init(void);
+
+	uint32_t _error_count {};
+	uint32_t _pulses_captured {};
+	uint32_t _last_period {};
+	uint32_t _last_width {};
+
+	bool _timer_started {};
+
+	pwm_input_s _pwm {};
+
+	uORB::PublicationData<pwm_input_s> _pwm_input_pub{ORB_ID(pwm_input)};
+
+};

src/modules/commander/failure_detector/FailureDetector.cpp

@@ -40,6 +40,8 @@
 
 #include "FailureDetector.hpp"
 
+using namespace time_literals;
+
 FailureDetector::FailureDetector(ModuleParams *parent) :
 	ModuleParams(parent)
 {
@@ -61,6 +63,10 @@ FailureDetector::update(const vehicle_status_s &vehicle_status)
 	if (isAttitudeStabilized(vehicle_status)) {
 		updated = updateAttitudeStatus();
 
+		if (_param_fd_ext_ats_en.get()) {
+			updated |= updateExternalAtsStatus();
+		}
+
 	} else {
 		updated = resetStatus();
 	}
@@ -111,8 +117,8 @@ FailureDetector::updateAttitudeStatus()
 		hrt_abstime time_now = hrt_absolute_time();
 
 		// Update hysteresis
-		_roll_failure_hysteresis.set_hysteresis_time_from(false, (hrt_abstime)(1e6f * _param_fd_fail_r_ttri.get()));
+		_roll_failure_hysteresis.set_hysteresis_time_from(false, (hrt_abstime)(1_s * _param_fd_fail_r_ttri.get()));
-		_pitch_failure_hysteresis.set_hysteresis_time_from(false, (hrt_abstime)(1e6f * _param_fd_fail_p_ttri.get()));
+		_pitch_failure_hysteresis.set_hysteresis_time_from(false, (hrt_abstime)(1_s * _param_fd_fail_p_ttri.get()));
 		_roll_failure_hysteresis.set_state_and_update(roll_status, time_now);
 		_pitch_failure_hysteresis.set_state_and_update(pitch_status, time_now);
 
@@ -132,3 +138,30 @@ FailureDetector::updateAttitudeStatus()
 
 	return updated;
 }
+
+bool
+FailureDetector::updateExternalAtsStatus()
+{
+	pwm_input_s pwm_input;
+	bool updated = _sub_pwm_input.update(&pwm_input);
+
+	if (updated) {
+
+		uint32_t pulse_width = pwm_input.pulse_width;
+		bool ats_trigger_status = (pulse_width >= (uint32_t)_param_fd_ext_ats_trig.get()) && (pulse_width < 3_ms);
+
+		hrt_abstime time_now = hrt_absolute_time();
+
+		// Update hysteresis
+		_ext_ats_failure_hysteresis.set_hysteresis_time_from(false, 100_ms); // 5 consecutive pulses at 50hz
+		_ext_ats_failure_hysteresis.set_state_and_update(ats_trigger_status, time_now);
+
+		_status &= ~FAILURE_EXT;
+
+		if (_ext_ats_failure_hysteresis.get_state()) {
+			_status |= FAILURE_EXT;
+		}
+	}
+
+	return updated;
+}

src/modules/commander/failure_detector/FailureDetector.hpp

@@ -48,17 +48,20 @@
 #include <px4_platform_common/module_params.h>
 #include <hysteresis/hysteresis.h>
 
+
 // subscriptions
 #include <uORB/Subscription.hpp>
 #include <uORB/topics/vehicle_attitude_setpoint.h>
 #include <uORB/topics/vehicle_attitude.h>
 #include <uORB/topics/vehicle_status.h>
+#include <uORB/topics/pwm_input.h>
 
 typedef enum {
 	FAILURE_NONE = vehicle_status_s::FAILURE_NONE,
 	FAILURE_ROLL = vehicle_status_s::FAILURE_ROLL,
 	FAILURE_PITCH = vehicle_status_s::FAILURE_PITCH,
 	FAILURE_ALT = vehicle_status_s::FAILURE_ALT,
+	FAILURE_EXT = vehicle_status_s::FAILURE_EXT,
 } failure_detector_bitmak;
 
 using uORB::SubscriptionData;
@@ -79,18 +82,24 @@ private:
 		(ParamInt<px4::params::FD_FAIL_P>) _param_fd_fail_p,
 		(ParamInt<px4::params::FD_FAIL_R>) _param_fd_fail_r,
 		(ParamFloat<px4::params::FD_FAIL_R_TTRI>) _param_fd_fail_r_ttri,
-		(ParamFloat<px4::params::FD_FAIL_P_TTRI>) _param_fd_fail_p_ttri
+		(ParamFloat<px4::params::FD_FAIL_P_TTRI>) _param_fd_fail_p_ttri,
+		(ParamBool<px4::params::FD_EXT_ATS_EN>) _param_fd_ext_ats_en,
+		(ParamInt<px4::params::FD_EXT_ATS_TRIG>) _param_fd_ext_ats_trig
 	)
 
 	// Subscriptions
 	uORB::Subscription _sub_vehicule_attitude{ORB_ID(vehicle_attitude)};
+	uORB::Subscription _sub_pwm_input{ORB_ID(pwm_input)};
+
 
 	uint8_t _status{FAILURE_NONE};
 
 	systemlib::Hysteresis _roll_failure_hysteresis{false};
 	systemlib::Hysteresis _pitch_failure_hysteresis{false};
+	systemlib::Hysteresis _ext_ats_failure_hysteresis{false};
 
 	bool resetStatus();
 	bool isAttitudeStabilized(const vehicle_status_s &vehicle_status);
 	bool updateAttitudeStatus();
+	bool updateExternalAtsStatus();
 };

src/modules/commander/failure_detector/failure_detector_params.c

@@ -103,3 +103,27 @@ PARAM_DEFINE_FLOAT(FD_FAIL_R_TTRI, 0.3);
  * @group Failure Detector
  */
 PARAM_DEFINE_FLOAT(FD_FAIL_P_TTRI, 0.3);
+
+/**
+ * Enable PWM input on AUX5 or MAIN5 (depending on board) for engaging failsafe from an external
+ * automatic trigger system (ATS).
+ *
+ * External ATS is required by ASTM F3322-18.
+ *
+ * @boolean
+ * @reboot_required true
+ * @group Failure Detector
+ */
+PARAM_DEFINE_INT32(FD_EXT_ATS_EN, 0);
+
+/**
+ * The PWM threshold from external automatic trigger system for engaging failsafe.
+ *
+ * External ATS is required by ASTM F3322-18.
+ *
+ * @unit microseconds
+ * @decimal 2
+ *
+ * @group Failure Detector
+ */
+PARAM_DEFINE_INT32(FD_EXT_ATS_TRIG, 1900);