hysteresis.cpp
2.77 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
/****************************************************************************
*
* Copyright (c) 2016-2019 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.
*
****************************************************************************/
/**
* @file hysteresis.cpp
*
* @author Julian Oes <julian@oes.ch>
*/
#include "hysteresis.h"
namespace systemlib
{
void
Hysteresis::set_hysteresis_time_from(const bool from_state, const hrt_abstime new_hysteresis_time_us)
{
if (from_state) {
_time_from_true_us = new_hysteresis_time_us;
} else {
_time_from_false_us = new_hysteresis_time_us;
}
}
void
Hysteresis::set_state_and_update(const bool new_state, const hrt_abstime &now_us)
{
if (new_state != _state) {
if (new_state != _requested_state) {
_requested_state = new_state;
_last_time_to_change_state = now_us;
}
} else {
_requested_state = _state;
}
update(now_us);
}
void
Hysteresis::update(const hrt_abstime &now_us)
{
if (_requested_state != _state) {
const hrt_abstime elapsed = now_us - _last_time_to_change_state;
if (_state && !_requested_state) {
// true -> false
if (elapsed >= _time_from_true_us) {
_state = false;
}
} else if (!_state && _requested_state) {
// false -> true
if (elapsed >= _time_from_false_us) {
_state = true;
}
}
}
}
} // namespace systemlib