Package PID Controller:

- add package to calculate range of value for Progressive Integrate Derivative

Package Duration:
- add function to parse float64 to Duration
- add function to return a PID Duration range from another given duration
- add function to return a PID Duration range to another given duration

pidcontroller/model.go

@@ -0,0 +1,61 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2024 Nicolas JUHEL
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ */
+
+package pidcontroller
+
+// PID (Proportional Integral Derivative controller)
+type pid struct {
+	kp float64 // rate proportional
+	ki float64 // rate integral
+	kd float64 // rate derivative
+
+	prevError float64
+	integral  float64
+}
+
+func (p *pid) calc(end, actual float64) float64 {
+	pidError := end - actual
+	p.integral += pidError
+	derive := pidError - p.prevError
+
+	output := p.kp*pidError + p.ki*p.integral + p.kd*derive
+	p.prevError = pidError
+
+	return output
+}
+
+func (p *pid) Range(min, max float64) []float64 {
+	var res = make([]float64, 0)
+
+	for {
+		min += p.calc(max, min)
+
+		if min > max {
+			return append(res, max)
+		} else {
+			res = append(res, min)
+		}
+	}
+}