view Common/Inc/decom.h @ 224:ceecabfddb57 div-fixes-3

Bugfix, deco: fix 2 (small) problems with calculated ceiling This fixes 1 trivial, and 1 not really trivial bug in the calculation of the ceiling. When simulating a bounce dive to 80m, things become clear (tried this on a CCR dive, fixed setpoint 1.2bar, about 15 minutes of bottom time). Closely watch the behavior of the ceiling data. At some point during the ascent, the ceiling begins to decrease in 10cm steps. Then suddenly (while still ascending), the ceiling increases again with 1m, does not change for some time, and then suddenly steps 1.1m less deep. While not very relevant to real deco diving, it is simply wrong. The reason for this is subtle. The algorithm used to find the ceiling is a sort of linear search, stepping down a meter, overshoot the depth, and search back in 10cm steps. It seems some numerical instability. Fixing this, was a bit more computational intensive search by stepping up down in equal steps of 10cm. But, I'm pretty sure that things can be speeded up here, as a ceiling does not change fast, so it should be not that difficult to limit the search space, or use a binary search algorithm instead. The trivial second problem fixed, is that the ceiling ends at the surface and not at 1m depth. This small issue became visible after changing the step down size above. Signed-off-by: Jan Mulder <jlmulder@xs4all.nl>
author Jan Mulder <jlmulder@xs4all.nl>
date Sun, 31 Mar 2019 19:35:51 +0200
parents 239aa58b533d
children 1b995079c045
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///////////////////////////////////////////////////////////////////////////////
/// -*- coding: UTF-8 -*-
///
/// \file   Common/Inc/decom.h
/// \brief  This code is used to calculate desat, calculated by RTE and send to Firmware
/// \author Heinrichs Weikamp
/// \date   22-Feb-2016
///
/// $Id$
///////////////////////////////////////////////////////////////////////////////
/// \par Copyright (c) 2014-2018 Heinrichs Weikamp gmbh
///
///     This program is free software: you can redistribute it and/or modify
///     it under the terms of the GNU General Public License as published by
///     the Free Software Foundation, either version 3 of the License, or
///     (at your option) any later version.
///
///     This program is distributed in the hope that it will be useful,
///     but WITHOUT ANY WARRANTY; without even the implied warranty of
///     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
///     GNU General Public License for more details.
///
///     You should have received a copy of the GNU General Public License
///     along with this program.  If not, see <http://www.gnu.org/licenses/>.
//////////////////////////////////////////////////////////////////////////////

#ifndef DECOM_H
#define DECOM_H

#include "data_central.h"

#	define	WATER_VAPOUR_PRESSURE	(0.0493f) // Schreiner 1971

void decom_get_inert_gases(const float ambient_pressure_bar,const SGas* pGas, float* fraction_nitrogen, float* fraction_helium );
void decom_tissues_exposure(int period_in_seconds, SLifeData* pLifeData);
void decom_tissues_exposure2(int period_in_seconds, SGas* pActualGas, float pressure_ambient_bar, float *tissue_N2_selected_stage, float *tissue_He_selected_stage);
float decom_schreiner_equation(float *initial_inspired_gas_pressure, float *rate_change_insp_gas_pressure, float *interval_time_minutes, const float *gas_time_constant, float *initial_gas_pressure);
void decom_reset_with_1000mbar(SLifeData * pLifeData);
void decom_reset_with_ambientmbar(float ambient, SLifeData * pLifeData);

void decom_tissues_exposure_stage_schreiner(int period_in_seconds, SGas* pGas, float  starting_ambient_pressure_bar, float ending_ambient_pressure_bar,
																		 float* pTissue_nitrogen_bar, float* pTissue_helium_bar);
void decom_CreateGasChangeList(SDiveSettings* pInput, const SLifeData* lifeData);
uint8_t decom_tissue_test_tolerance(float* Tissue_nitrogen_bar, float* Tissue_helium_bar, float GF_value, float depth_in_bar_absolute);
void decom_tissues_desaturation_time(const SLifeData* pLifeData, SLifeData2* pOutput);
void test_decom_CreateGasChangeList(void);

float decom_calc_ppO2(const float ambiant_pressure_bar, const SGas* pGas);
void decom_oxygen_calculate_otu(float* oxygen_otu, float pressure_oxygen_real);
void decom_oxygen_calculate_otu_degrade(float* oxygen_otu, long seconds_since_last_dive);
void decom_oxygen_calculate_cns_degrade(float* oxygen_cns, long seconds_since_last_dive);
void decom_oxygen_calculate_cns(float* oxygen_cns, float pressure_oxygen_real);
void decom_oxygen_calculate_cns_stage_SchreinerStyle(int period_in_seconds, SGas* pGas, float  starting_ambient_pressure_bar, float ending_ambient_pressure_bar, float* oxygen_cns);
void decom_oxygen_calculate_cns_exposure(int period_in_seconds, SGas* pActualGas, float pressure_ambient_bar, float* oxygen_cns);
uint8_t decom_get_actual_deco_stop(SDiveState* pDiveState);

// wird nur in smallCPU verwendet:
int decom_calc_desaturation_time(float* Tissue_nitrogen_bar, float* Tissue_helium_bar, float surface_pressure_bar);

#endif /* DECOM_H */