/*
- * Copyright (C) 2014 Intel Corporation.
- */
+// Copyright (c) 2015 Intel Corporation
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+*/
#ifndef __CALIBRATION_H__
#define __CALIBRATION_H__
#include "common.h"
-/* compass defines */
-#define COMPASS_CALIBRATION_PATH "/data/compass.conf"
-#define DS_SIZE 48
-#define EPSILON 0.000000001
+#define MAGN_DS_SIZE 32
-/* If no cal data is present - first calibration will
- use a more relaxed set of values to get an initial
- calibration faster */
-#define FIRST_MIN_DIFF 0.5f
-#define FIRST_MAX_SQR_ERR 5.0f
-#define FIRST_LOOKBACK_COUNT 4
-
-#define MIN_DIFF 1.0f
-#define MAX_SQR_ERR 3.5f
-#define LOOKBACK_COUNT 6
-
-
-#ifdef DBG_RAW_DATA
-#define RAW_DATA_FULL_PATH "/data/raw_compass_data_full_%d.txt"
-#define RAW_DATA_SELECTED_PATH "/data/raw_compass_data_selected_%d.txt"
-#endif
-
-/* gyro defines */
-#define GYRO_MAX_ERR 0.05f
-#define GYRO_DS_SIZE 8
-
typedef struct {
/* hard iron offsets */
double offset[3][1];
/* geomagnetic strength */
double bfield;
-} calibration_data;
+ /* selection data */
+ float sample[MAGN_DS_SIZE][3];
+ unsigned int sample_count;
+ float average[3];
+}
+compass_cal_t;
+
-struct gyro_cal {
- float bias[3];
- int start;
+typedef struct {
+ float bias_x, bias_y, bias_z;
int count;
- float sample[GYRO_DS_SIZE][3];
-};
+ float min_x, min_y, min_z;
+ float max_x, max_y, max_z;
+}
+gyro_cal_t;
+
+/* Accelerometer bias estimation and compensation */
+
+#define BUCKET_COUNT 3
+#define BUCKET_TOLERANCE 2.5 /* Maximum monitoring distance from value of interest, in m/s² */
+#define SLICES 100 /* We currently have 3 buckets per axis, and 100 slices per bucket ; then we distribute incoming samples among slices */
+
+typedef struct
+{
+ int version;
+ int bucket_count;
+ int slices;
+ float bucket_tolerance;
+
+ uint64_t bucket[3][BUCKET_COUNT][SLICES]; /* How many samples fell in each of the slices, per axis */
+ uint64_t bucket_usage[3][BUCKET_COUNT]; /* How many samples fell in each of the buckets (= sum of the slice counts) */
+
+ /* Estimated bias, according to accumulated data */
+ float accel_bias_x;
+ float accel_bias_y;
+ float accel_bias_z;
+
+ uint64_t last_estimation_ts;
+}
+accel_cal_t;
+
+
+typedef double mat_input_t[MAGN_DS_SIZE][3];
+
+
+void calibrate_compass (int s, sensors_event_t* event);
+void compass_read_data (int s);
+void compass_store_data (int s);
-typedef double mat_input_t[DS_SIZE][3];
+void calibrate_gyro (int s, sensors_event_t* event);
+void gyro_cal_init (int s);
+void gyro_store_data (int s);
-void calibrate_compass (struct sensors_event_t* event, int64_t time);
-void compass_read_data (const char* config_path);
-void compass_store_data (const char* config_path);
+void calibrate_accel (int s, sensors_event_t* event);
+void accel_cal_init (int s);
+void accel_cal_store (int s);
-void calibrate_gyro(struct sensors_event_t* event, struct sensor_info_t* info);
-void gyro_cal_init(struct sensor_info_t* info);
#endif