example_detector_distance_calibration_caching.c

This is an example on how the sensor and detector calibration can be cached
This example executes as follows:

// Copyright (c) Acconeer AB, 2024
// All rights reserved
// This file is subject to the terms and conditions defined in the file
// 'LICENSES/license_acconeer.txt', (BSD 3-Clause License) which is part
// of this source code package.
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include "acc_rss_a121.h"
#include "acc_sensor.h"
#include "acc_version.h"
/** \example example_detector_distance_calibration_caching.c
* @brief This is an example on how the sensor and detector calibration can be cached
* @n
* This example executes as follows:
* - Retrieve and register HAL struct
* - Create and initialize distance detector resources
* - Create and calibrate sensor
* - Calibrate detector
* - Loop:
* - Prepare, measure, read, process data using the detector
* - Check 'calibration_needed' indication
* - If needed, either use cached calibration or perform new calibration and store
* - Destroy resources
*/
#define SENSOR_ID (1U)
// 2 seconds should be enough even for long ranges and high signal quality
#define SENSOR_TIMEOUT_MS (2000U)
/**
* A sensor calibration and the dynamic part of a detector calibration are valid at the
* temperature they were done +- 15 degrees.
*
* If the temperature isn't controlled during caching, which is the case in this example,
* the maximum amount of caches needs to be calculated from a temperature difference of 16.
*
* For example
* - A calibration is done at 25 degrees, which means it is valid between 10 and 40 degrees
* - The temperature changes to 41 degrees
* - A new calibration needs to be done at 41 degrees since it is above the valid range for the previous calibration
* - The new calibration is then valid between 26 and 56 degrees
*
* However, if the temperature is controlled, for example in a factory, the maximum amount
* of caches can be calculated from a temperature difference of 30.
*
* For example
* - A calibration is done at 25 degrees, which means it is valid between 10 and 40 degrees
* - The temperature is manually changed to 55 degrees
* - A new calibration can be done which is valid between 40 and 70 degrees
*
* The maximum temperature variation that the application will operate in is assumed to be
* -40 to 85 degrees in this example.
*/
#define MAX_CAL_TEMP_DIFF (16)
#define MAX_TEMP_VARIATION (125)
#define MAX_CACHE_COUNT ((MAX_TEMP_VARIATION / MAX_CAL_TEMP_DIFF) + 1)
// Variables for temperature independent caching
static uint32_t detector_cal_result_static_size = 0;
// Variables for temperature dependent caching
static int16_t cal_temps[MAX_CACHE_COUNT];
static uint16_t curr_cache_count = 0;
static uint16_t cache_index_in_use = 0;
typedef struct
{
acc_sensor_t *sensor;
void *buffer;
uint32_t buffer_size;
// General control functions
static void set_config(acc_detector_distance_config_t *detector_config);
static void cleanup(distance_detector_resources_t *resources);
// Calibration and caching functions
static bool sensor_and_detector_calibration(distance_detector_resources_t *resources, uint16_t cache_index);
static bool sensor_calibration(distance_detector_resources_t *resources, uint16_t cache_index);
static bool detector_calibration_full(distance_detector_resources_t *resources, uint16_t cache_index);
static bool detector_calibration_update(distance_detector_resources_t *resources, uint16_t cache_index);
static bool calibration_caching(distance_detector_resources_t *resources, int16_t temp);
// Caching helper functions
static bool find_cache_index(int16_t temp, uint16_t *cache_index);
static bool get_next_empty_cache_index(uint16_t *cache_index);
static bool add_cache(uint16_t cache_index, int16_t temp);
// Main function
int app_main(int argc, char *argv[]);
int app_main(int argc, char *argv[])
{
(void)argc;
(void)argv;
distance_detector_resources_t resources = { 0 };
printf("Acconeer software version %s\n", acc_version_get());
{
return EXIT_FAILURE;
}
if (resources.config == NULL)
{
printf("Config creation failed\n");
return EXIT_FAILURE;
}
set_config(resources.config);
{
printf("Initializing detector resources failed\n");
cleanup(&resources);
return EXIT_FAILURE;
}
if (resources.sensor == NULL)
{
printf("Sensor creation failed\n");
cleanup(&resources);
return EXIT_FAILURE;
}
// Do a sensor calibration and a full detector calibration and store first in cache.
if (!sensor_and_detector_calibration(&resources, 0))
{
printf("Sensor or detector calibration failed\n");
cleanup(&resources);
return EXIT_FAILURE;
}
uint32_t update_count = 5U;
for (uint32_t i = 0U; i < update_count; i++)
{
if (!detector_get_next(&resources, &result))
{
printf("Could not get next result\n");
cleanup(&resources);
return EXIT_FAILURE;
}
if (result.calibration_needed)
{
printf("New calibrations needed due to temperature change\n");
if (!calibration_caching(&resources, result.temperature))
{
printf("Calibration caching failed\n");
cleanup(&resources);
return EXIT_FAILURE;
}
}
else
{
printf("Distance result retrieved\n");
}
}
cleanup(&resources);
printf("Application finished OK\n");
return EXIT_SUCCESS;
}
// General control functions
static void set_config(acc_detector_distance_config_t *detector_config)
{
// Balanced detector config
acc_detector_distance_config_start_set(detector_config, 0.25f);
acc_detector_distance_config_end_set(detector_config, 3.0f);
}
{
resources->handle = acc_detector_distance_create(resources->config);
if (resources->handle == NULL)
{
printf("acc_detector_distance_create() failed\n");
return false;
}
{
printf("acc_detector_distance_get_sizes() failed\n");
return false;
}
resources->buffer = acc_integration_mem_alloc(resources->buffer_size);
if (resources->buffer == NULL)
{
printf("sensor buffer allocation failed\n");
return false;
}
{
printf("static cal result allocation failed\n");
return false;
}
return true;
}
{
bool result_available = false;
do
{
resources->buffer,
resources->buffer_size))
{
printf("acc_detector_distance_prepare() failed\n");
return false;
}
if (!acc_sensor_measure(resources->sensor))
{
printf("acc_sensor_measure() failed\n");
return false;
}
{
printf("Sensor interrupt timeout\n");
return false;
}
if (!acc_sensor_read(resources->sensor, resources->buffer, resources->buffer_size))
{
printf("acc_sensor_read() failed\n");
return false;
}
&result_available, result))
{
printf("acc_detector_distance_process() failed\n");
return false;
}
} while (!result_available);
return true;
}
static void cleanup(distance_detector_resources_t *resources)
{
if (resources->sensor != NULL)
{
}
{
}
if (resources->buffer != NULL)
{
}
if (resources->handle != NULL)
{
}
if (resources->config != NULL)
{
}
}
// Calibration and caching functions
static bool sensor_and_detector_calibration(distance_detector_resources_t *resources, uint16_t cache_index)
{
bool status = sensor_calibration(resources, cache_index);
if (status)
{
status = detector_calibration_full(resources, cache_index);
}
if (status)
{
acc_cal_info_t cal_info;
acc_sensor_get_cal_info(&sensor_cal_results[cache_index], &cal_info);
add_cache(cache_index, cal_info.temperature);
cache_index_in_use = cache_index;
}
return status;
}
static bool sensor_calibration(distance_detector_resources_t *resources, uint16_t cache_index)
{
bool status = false;
bool cal_complete = false;
const uint16_t calibration_retries = 1U;
// Random disturbances may cause the calibration to fail. At failure, retry at least once.
for (uint16_t i = 0; !status && (i <= calibration_retries); i++)
{
// Reset sensor before calibration by disabling/enabling it
do
{
status = acc_sensor_calibrate(resources->sensor, &cal_complete, &sensor_cal_results[cache_index], resources->buffer,
resources->buffer_size);
if (status && !cal_complete)
{
}
} while (status && !cal_complete);
}
if (status)
{
// Reset sensor after calibration by disabling/enabling it
}
return status;
}
static bool detector_calibration_full(distance_detector_resources_t *resources, uint16_t cache_index)
{
bool status = false;
bool cal_complete = false;
do
{
resources->handle,
&sensor_cal_results[cache_index],
resources->buffer,
resources->buffer_size,
&cal_complete);
if (status && !cal_complete)
{
}
} while (status && !cal_complete);
return status;
}
static bool detector_calibration_update(distance_detector_resources_t *resources, uint16_t cache_index)
{
bool status = false;
bool cal_complete = false;
do
{
resources->handle,
&sensor_cal_results[cache_index],
resources->buffer,
resources->buffer_size,
&cal_complete);
if (status && !cal_complete)
{
}
} while (status && !cal_complete);
return status;
}
static bool calibration_caching(distance_detector_resources_t *resources, int16_t temp)
{
bool status = true;
uint16_t cache_index = 0;
bool use_cache = find_cache_index(temp, &cache_index);
// If no cached calibration can be used, a new calibration should be made
// and the result stored at an empty cache_index
if (!use_cache)
{
printf("New sensor calibration and detector calibration update is performed\n");
if (!get_next_empty_cache_index(&cache_index))
{
printf("No empty cache_index to store calibration result\n");
return false;
}
status = sensor_calibration(resources, cache_index);
if (status)
{
status = detector_calibration_update(resources, cache_index);
}
if (status)
{
acc_cal_info_t cal_info;
acc_sensor_get_cal_info(&sensor_cal_results[cache_index], &cal_info);
add_cache(cache_index, cal_info.temperature);
cache_index_in_use = cache_index;
}
}
else
{
cache_index_in_use = cache_index;
printf("Using cached calibration for %u degrees Celsius\n", cal_temps[cache_index_in_use]);
}
return status;
}
// Caching helper functions
static bool find_cache_index(int16_t temp, uint16_t *cache_index)
{
bool cache_found = false;
uint16_t min_temp_diff = UINT16_MAX;
// If caches have overlapping temperature ranges, the cache
// with center temperature closest to 'temp' will be chosen
for (uint16_t index = 0; index < curr_cache_count; index++)
{
uint16_t temp_diff = abs(cal_temps[index] - temp);
if (temp_diff < MAX_CAL_TEMP_DIFF && temp_diff < min_temp_diff)
{
min_temp_diff = temp_diff;
*cache_index = index;
cache_found = true;
}
}
return cache_found;
}
static bool get_next_empty_cache_index(uint16_t *cache_index)
{
*cache_index = curr_cache_count;
}
static bool add_cache(uint16_t cache_index, int16_t temp)
{
bool status = false;
if ((cache_index == curr_cache_count) && (cache_index < MAX_CACHE_COUNT))
{
cal_temps[cache_index] = temp;
status = true;
}
return status;
}
MAX_CAL_TEMP_DIFF
#define MAX_CAL_TEMP_DIFF
Definition: example_detector_distance_calibration_caching.c:68
ACC_DETECTOR_DISTANCE_REFLECTOR_SHAPE_GENERIC
@ ACC_DETECTOR_DISTANCE_REFLECTOR_SHAPE_GENERIC
Definition: acc_detector_distance_definitions.h:59
calibration_caching
static bool calibration_caching(distance_detector_resources_t *resources, int16_t temp)
Definition: example_detector_distance_calibration_caching.c:467
detector_cal_results_dynamic
static acc_detector_cal_result_dynamic_t detector_cal_results_dynamic[(((125)/(16))+1)]
Definition: example_detector_distance_calibration_caching.c:78
acc_hal_integration_sensor_supply_off
void acc_hal_integration_sensor_supply_off(acc_sensor_id_t sensor_id)
Power off sensor supply.
Definition: acc_hal_integration_espidf_xe121.c:192
acc_rss_a121.h
acc_detector_distance_get_sizes
bool acc_detector_distance_get_sizes(const acc_detector_distance_handle_t *handle, uint32_t *buffer_size, uint32_t *detector_cal_result_static_size)
Get the sizes needed given the provided detector handle.
get_next_empty_cache_index
static bool get_next_empty_cache_index(uint16_t *cache_index)
Definition: example_detector_distance_calibration_caching.c:534
acc_detector_distance_config_peak_sorting_set
void acc_detector_distance_config_peak_sorting_set(acc_detector_distance_config_t *config, acc_detector_distance_peak_sorting_t peak_sorting)
Set the peak sorting method.
cache_index_in_use
static uint16_t cache_index_in_use
Definition: example_detector_distance_calibration_caching.c:81
acc_hal_integration_sensor_supply_on
void acc_hal_integration_sensor_supply_on(acc_sensor_id_t sensor_id)
Power on sensor supply.
Definition: acc_hal_integration_espidf_xe121.c:185
SENSOR_ID
#define SENSOR_ID
Definition: example_detector_distance_calibration_caching.c:39
acc_cal_info_t
Information about calibration.
Definition: acc_definitions_a121.h:40
sensor_cal_results
static acc_cal_result_t sensor_cal_results[(((125)/(16))+1)]
Definition: example_detector_distance_calibration_caching.c:77
acc_sensor_read
bool acc_sensor_read(const acc_sensor_t *sensor, void *buffer, uint32_t buffer_size)
Read out radar data.
acc_detector_distance_result_t::temperature
int16_t temperature
Definition: acc_detector_distance.h:81
acc_version.h
ACC_DETECTOR_DISTANCE_PEAK_SORTING_STRONGEST
@ ACC_DETECTOR_DISTANCE_PEAK_SORTING_STRONGEST
Definition: acc_detector_distance_definitions.h:33
detector_get_next
static bool detector_get_next(distance_detector_resources_t *resources, acc_detector_distance_result_t *result)
Definition: example_detector_distance_calibration_caching.c:279
distance_detector_resources_t::buffer_size
uint32_t buffer_size
Definition: example_detector_distance.c:68
acc_detector_distance_config_threshold_method_set
void acc_detector_distance_config_threshold_method_set(acc_detector_distance_config_t *config, acc_detector_distance_threshold_method_t threshold_method)
Set the threshold method.
acc_cal_result_t
The result from a completed calibration.
Definition: acc_definitions_a121.h:32
acc_detector_distance_config_start_set
void acc_detector_distance_config_start_set(acc_detector_distance_config_t *config, float start_m)
Set the start of measured interval in meters.
ACC_CONFIG_PROFILE_5
@ ACC_CONFIG_PROFILE_5
Definition: acc_definitions_a121.h:60
acc_integration.h
acc_detector_distance_create
acc_detector_distance_handle_t * acc_detector_distance_create(const acc_detector_distance_config_t *config)
Create a distance detector with the provided configuration.
sensor_and_detector_calibration
static bool sensor_and_detector_calibration(distance_detector_resources_t *resources, uint16_t cache_index)
Definition: example_detector_distance_calibration_caching.c:358
ACC_DETECTOR_DISTANCE_THRESHOLD_METHOD_CFAR
@ ACC_DETECTOR_DISTANCE_THRESHOLD_METHOD_CFAR
Definition: acc_detector_distance_definitions.h:49
acc_detector_distance_config_destroy
void acc_detector_distance_config_destroy(acc_detector_distance_config_t *config)
Destroy a configuration for a distance detector.
add_cache
static bool add_cache(uint16_t cache_index, int16_t temp)
Definition: example_detector_distance_calibration_caching.c:542
acc_hal_rss_integration_get_implementation
const acc_hal_a121_t * acc_hal_rss_integration_get_implementation(void)
Get hal implementation reference.
Definition: acc_hal_integration_espidf_xe121.c:135
acc_detector_distance_calibrate
bool acc_detector_distance_calibrate(acc_sensor_t *sensor, acc_detector_distance_handle_t *handle, const acc_cal_result_t *sensor_cal_result, void *buffer, uint32_t buffer_size, uint8_t *detector_cal_result_static, uint32_t detector_cal_result_static_size, acc_detector_cal_result_dynamic_t *detector_cal_result_dynamic, bool *calibration_complete)
Do a detector calibration.
acc_detector_distance_process
bool acc_detector_distance_process(acc_detector_distance_handle_t *handle, void *buffer, uint8_t *detector_cal_result_static, acc_detector_cal_result_dynamic_t *detector_cal_result_dynamic, bool *result_available, acc_detector_distance_result_t *result)
Process the data according to the configuration used in acc_detector_distance_config_create.
acc_integration_mem_alloc
void * acc_integration_mem_alloc(size_t size)
Allocate dynamic memory.
Definition: acc_integration_esp32.c:38
detector_calibration_update
static bool detector_calibration_update(distance_detector_resources_t *resources, uint16_t cache_index)
Definition: example_detector_distance_calibration_caching.c:442
detector_cal_result_static
static uint8_t * detector_cal_result_static
Definition: example_detector_distance_calibration_caching.c:73
acc_hal_a121_t
Definition: acc_hal_definitions_a121.h:82
acc_rss_hal_register
bool acc_rss_hal_register(const acc_hal_a121_t *hal)
Register an integration.
acc_sensor.h
acc_detector_cal_result_dynamic_t
Definition: acc_detector_distance_definitions.h:19
acc_detector_distance_config_close_range_leakage_cancellation_set
void acc_detector_distance_config_close_range_leakage_cancellation_set(acc_detector_distance_config_t *config, bool enable)
Enable the close range leakage cancellation logic.
distance_detector_resources_t
Definition: example_detector_distance.c:62
acc_detector_distance_config_max_profile_set
void acc_detector_distance_config_max_profile_set(acc_detector_distance_config_t *config, acc_config_profile_t max_profile)
Set the max profile.
acc_detector_distance_destroy
void acc_detector_distance_destroy(acc_detector_distance_handle_t *handle)
Destroy the distance detector handle, freeing its resources.
acc_hal_integration_wait_for_sensor_interrupt
bool acc_hal_integration_wait_for_sensor_interrupt(acc_sensor_id_t sensor_id, uint32_t timeout_ms)
Wait for a sensor interrupt.
Definition: acc_hal_integration_espidf_xe121.c:100
acc_hal_integration_a121.h
acc_detector_distance_config_signal_quality_set
void acc_detector_distance_config_signal_quality_set(acc_detector_distance_config_t *config, float signal_quality)
Set the signal quality.
acc_version_get
const char * acc_version_get(void)
Get the version of the Acconeer software.
MAX_CACHE_COUNT
#define MAX_CACHE_COUNT
Definition: example_detector_distance_calibration_caching.c:70
acc_sensor_get_cal_info
bool acc_sensor_get_cal_info(const acc_cal_result_t *cal_result, acc_cal_info_t *cal_info)
Gets calibration information from a calibration result.
detector_cal_result_static_size
static uint32_t detector_cal_result_static_size
Definition: example_detector_distance_calibration_caching.c:74
acc_hal_integration_sensor_enable
void acc_hal_integration_sensor_enable(acc_sensor_id_t sensor_id)
Enable sensor.
Definition: acc_hal_integration_espidf_xe121.c:199
sensor_calibration
static bool sensor_calibration(distance_detector_resources_t *resources, uint16_t cache_index)
Definition: example_detector_distance_calibration_caching.c:379
acc_hal_definitions_a121.h
curr_cache_count
static uint16_t curr_cache_count
Definition: example_detector_distance_calibration_caching.c:80
acc_detector_distance_result_t::calibration_needed
bool calibration_needed
Definition: acc_detector_distance.h:76
acc_detector_distance_config_log
void acc_detector_distance_config_log(const acc_detector_distance_handle_t *handle, const acc_detector_distance_config_t *config)
Print a configuration to the log.
acc_detector_distance_prepare
bool acc_detector_distance_prepare(const acc_detector_distance_handle_t *handle, const acc_detector_distance_config_t *config, acc_sensor_t *sensor, const acc_cal_result_t *sensor_cal_result, void *buffer, uint32_t buffer_size)
Prepare the detector for measurements.
acc_detector_distance_result_t
Distance detector result.
Definition: acc_detector_distance.h:50
distance_detector_resources_t::config
acc_detector_distance_config_t * config
Definition: example_detector_distance.c:65
acc_hal_integration_sensor_disable
void acc_hal_integration_sensor_disable(acc_sensor_id_t sensor_id)
Disable sensor.
Definition: acc_hal_integration_espidf_xe121.c:214
cal_temps
static int16_t cal_temps[(((125)/(16))+1)]
Definition: example_detector_distance_calibration_caching.c:79
acc_detector_distance_config_end_set
void acc_detector_distance_config_end_set(acc_detector_distance_config_t *config, float end_m)
Set the end of measured interval in meters.
acc_detector_distance_config_num_frames_recorded_threshold_set
void acc_detector_distance_config_num_frames_recorded_threshold_set(acc_detector_distance_config_t *config, uint16_t num_frames)
Set the number frames to use for recorded threshold.
acc_integration_log.h
acc_detector_distance_handle_t
struct acc_detector_distance_handle acc_detector_distance_handle_t
Definition: acc_detector_distance.h:36
cleanup
static void cleanup(distance_detector_resources_t *resources)
Definition: example_detector_distance_calibration_caching.c:325
initialize_detector_resources
static bool initialize_detector_resources(distance_detector_resources_t *resources)
Definition: example_detector_distance_calibration_caching.c:246
acc_detector_distance_update_calibration
bool acc_detector_distance_update_calibration(acc_sensor_t *sensor, acc_detector_distance_handle_t *handle, const acc_cal_result_t *sensor_cal_result, void *buffer, uint32_t buffer_size, acc_detector_cal_result_dynamic_t *detector_cal_result_dynamic, bool *calibration_complete)
Update the calibration.
detector_calibration_full
static bool detector_calibration_full(distance_detector_resources_t *resources, uint16_t cache_index)
Definition: example_detector_distance_calibration_caching.c:415
hal
static const acc_hal_a121_t hal
Definition: acc_hal_integration_espidf_xe121.c:121
acc_integration_mem_free
void acc_integration_mem_free(void *ptr)
Free dynamic memory.
Definition: acc_integration_esp32.c:57
acc_detector_distance_config_reflector_shape_set
void acc_detector_distance_config_reflector_shape_set(acc_detector_distance_config_t *config, acc_detector_distance_reflector_shape_t reflector_shape)
Set reflector shape.
distance_detector_resources_t::sensor
acc_sensor_t * sensor
Definition: example_detector_distance.c:64
acc_detector_distance_config_threshold_sensitivity_set
void acc_detector_distance_config_threshold_sensitivity_set(acc_detector_distance_config_t *config, float threshold_sensitivity)
Set threshold sensitivity.
acc_detector_distance_config_create
acc_detector_distance_config_t * acc_detector_distance_config_create(void)
Create a configuration for a distance detector.
SENSOR_TIMEOUT_MS
#define SENSOR_TIMEOUT_MS
Definition: example_detector_distance_calibration_caching.c:41
acc_detector_distance.h
acc_sensor_calibrate
bool acc_sensor_calibrate(acc_sensor_t *sensor, bool *cal_complete, acc_cal_result_t *cal_result, void *buffer, uint32_t buffer_size)
Calibrate a sensor.
distance_detector_resources_t::handle
acc_detector_distance_handle_t * handle
Definition: example_detector_distance.c:66
distance_detector_resources_t::buffer
void * buffer
Definition: example_detector_distance.c:67
acc_detector_distance_config_t
struct acc_detector_distance_config acc_detector_distance_config_t
Definition: acc_detector_distance.h:44
acc_cal_info_t::temperature
int16_t temperature
Definition: acc_definitions_a121.h:42
acc_detector_distance_config_max_step_length_set
void acc_detector_distance_config_max_step_length_set(acc_detector_distance_config_t *config, uint16_t max_step_length)
Set the maximum step length.
set_config
static void set_config(acc_detector_distance_config_t *detector_config)
Definition: example_detector_distance_calibration_caching.c:229
app_main
int app_main(int argc, char *argv[])
Assembly test example.
Definition: example_detector_distance_calibration_caching.c:138
acc_sensor_measure
bool acc_sensor_measure(acc_sensor_t *sensor)
Start a radar measurement with previously prepared configuration.
acc_sensor_t
struct acc_sensor acc_sensor_t
Definition: acc_sensor.h:31
find_cache_index
static bool find_cache_index(int16_t temp, uint16_t *cache_index)
Definition: example_detector_distance_calibration_caching.c:511
acc_sensor_destroy
void acc_sensor_destroy(acc_sensor_t *sensor)
Destroy a sensor instance freeing any resources allocated.
acc_definitions_a121.h
acc_sensor_create
acc_sensor_t * acc_sensor_create(acc_sensor_id_t sensor_id)
Create a sensor instance.