industrial_robot_traj_control/trajPlanning.cpp at main · nml0/industrial_robot_traj_control · GitHub

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
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193


#include "trajPlanning.h"

#include<iostream>

using namespace std;

// Sign function
int sign (double a)
{
	int s = 1;
	if (a>0)
	{
		s=1;
	}
	else if (a<0)
	{
		s=-1;
	}
	return s;
}

// Trajectory planner function
vector<double> trajectoryPlanner (double time,
								  double x_0,
							      double v_0,
							      int v_max,
								  int a_max,
						  		  double x_goal)

{

	//cout << "Input parameters are, time, pos, vel, max vel, max acc, goal " << time << " , " << x_0 << " , " << v_0 << " , " << v_max << " , " << a_max << " , " << x_goal << endl;

	vector<double> triplet(3,0); // Acc, Vel and Pos container initialized to 0

	// d: default cruise-phase direction
	double t_stop = abs(v_0/a_max);
	double x_stop;
	if (v_0 > 0)
	{
		x_stop = x_0 + v_0 * t_stop + 0.5 * (-a_max) * pow(t_stop,2);
	}
	else
	{
		x_stop = x_0 + v_0 * t_stop + 0.5 * (a_max) * pow(t_stop,2);
	}
	int d = sign (x_goal - x_stop);

	double t1, t2, t3;
	double d_t1,d_t2,d_t3;
	double d_x1,d_x3, x_1, x_2;

	double a_acc =  d * a_max;
	double a_dec = -d * a_max;
	double v     =  d * v_max;
	double v_abs = 0;
	double inside_root = 0;

	// Acc and dec stages times
	d_t1 = (v-v_0)/a_acc;
	d_t3 = -v/a_dec;

	d_x1 = v_0 * d_t1 + 0.5 * a_acc * pow(d_t1,2);
	d_x3 = v * d_t3   + 0.5 * a_dec * pow(d_t3,2);

	d_t2 = (x_goal - (x_0 + d_x1 + d_x3))/v;


	// If d_t2 < 0 -> Overshoot, vel profile is wedge-shaped
	if (d_t2 < 0)
	{
		//cout << "Overshoot" << endl;
		inside_root = (d * a_max * (x_goal-x_0) + 0.5 * pow(v_0,2));
		if (inside_root < 0)
		{
			inside_root = 0;
		}
		double v_abs = sqrt (inside_root);


		//double v_abs = sqrt (d * a_max * (x_goal-x_0) + 0.5 * pow(v_0,2));
		//cout << "inside sqrt is " << (d * a_max * (x_goal-x_0) + 0.5 * pow(v_0,2)) << endl;
		//cout << "v_abs is " << v_abs << endl;
		d_t1 = abs((d*v_abs - v_0)/a_acc);
		//cout << "dt1 is " << d_t1 <<endl;
		d_t2 = 0;
		//cout << "dt2 is " << d_t2 <<endl;
		d_t3 = -(d*v_abs)/a_dec;
		//cout << "dt3 is " << d_t3 <<endl;

	}


	// if (d_t2 < 0)
	// {
	// 	//cout << "Overshoot" << endl;
	// 	double v_abs = sqrt (d * a_max * (x_goal-x_0) + 0.5 * pow(v_0,2));
	// 	d_t1 = abs((d*v_abs - v_0)/a_acc);
	// 	//cout << "dt1 is " << d_t1 <<endl;
	// 	d_t2 = 0;
	// 	//cout << "dt2 is " << d_t2 <<endl;
	// 	d_t3 = -(d*v_abs)/a_dec;
	// 	//cout << "dt3 is " << d_t3 <<endl;

	// }

	t1 = d_t1;
	t2 = d_t1 + d_t2;
	t3 = d_t1 + d_t2 + d_t3;

	//cout << "t1, t2, t3 are " << t1 << " , " << t2 << " , " << t3 << endl;

	int stage;
	if (time < t1)
	{
		stage = 1;
	}
	else if (time >= t1 && time < t2 )
	{
		stage = 2;
	}
	else if (time >= t2 && time < t3)
	{
		stage = 3;
	}
	else if (time >= t3)
	{
		stage = 4;
	}


	switch(stage)
	{

    	case 1 :
		//cout << "Acceleration phase" << endl;
		triplet[0] = a_acc;
		triplet[1] = v_0 + a_acc * time;
		triplet[2] = x_0 + v_0   * time + 0.5 * a_acc * pow(time,2) ;
		break;

		case 2 :
		//cout << "Cruise phase" << endl;
		triplet[0] = 0;
		triplet[1] = v;
		//cout << "Loaded velocity is " << v << endl;
		x_1 = x_0 + v_0 * t1 + 0.5 * a_acc * pow(t1,2);
		triplet[2] = x_1  + v * (time-t1) ;
		break;

		case 3 :
		if (d_t2 != 0)
		{
			//cout << "Deceleration phase" << endl;
			triplet[0]  = a_dec;
			triplet[1]  = v + a_dec * (time-t2);
			x_1 = x_0 + v_0 * t1 + 0.5 * a_acc * pow(t1,2);
			x_2 = x_1 + v * (d_t2);
			triplet[2]  = x_2 + v * (time-t2) + 0.5 * a_dec * pow((time-t2),2) ;
		}
		else
		{
			//cout << "Deceleration phase" << endl;
			triplet[0]  = a_dec;
			triplet[1]  = v_0 + a_acc * t1 + a_dec * (time-t2);
			x_1 = x_0 + v_0 * t1 + 0.5 * a_acc * pow(t1,2);
			triplet[2]  = x_1 + (v_0 + a_acc * t1) * (time-t2) + 0.5 * a_dec * pow((time-t2),2)  ;
		}
		break;

		case 4 :
		//cout << "At Target phase" << endl;
		triplet[0] = 0;
		triplet[1] = 0;
		triplet[2] = x_goal ;
		break;
	}

	return triplet;

}