pid参数的修改方法

无论是电流环、速度环或者位置环，执行器控制芯片的flash中虽然有一个默认的pid值，但是用户在使用的过程中仍然可以实时地对其进行修改，要修改pd值只需要在进入任意一个操作模式后发送对应的报文即可，报文内容请见通讯协议介绍。

电流环pi：

顾名思义，电流环pi用于更改电流的调节速率(相同的参数在不同型号的执行器会有不同的情况，这里以TA70-101型号为例)，例如：

执行器默认的电流环kp、ki值分别为0.0006、0.0001，此时电流从0增大到1000mA大约需要1.3s，如图：

将kp、ki值分别设为0.02，0.002后，电流从0增大到1000mA大约需要0.2s，如图：

❗

注意：在使用轮廓速度模式或轮廓位置模式时，电流环pi不宜设置过大，否则执行器将发生剧烈抖动

速度环pi：

如图为速度环kp、ki值分别为25，0.6时的速度变化曲线

如图为速度环kp、ki值分别为100、2.4时的速度变化曲线

速度环pi用于控制速度调节的能力，当pi值增大时，实际速度超调现象减弱，速度震荡幅度也有所减小，pi值减小时则相反。速度的变化速率则由加（减）速度决定，这两个值也可以实时更改，修改方法与pid值修改方法类似。

位置环pd：

位置环作用于轮廓位置模式，用于控制参考速度的大小，在给定相同的位置差时，kp值越大，则执行器参考速度越大，kd则用于减缓参考速度的变化速率。

如图为kp、kd分别为0.004、0时的速度变化曲线：

如图为kp、kd分别为0.016、0时的速度变化曲线，

SDK:

实时修改电流环PI

C++:

#include <motor_control.h>
string port_name = "COM3";                     // Windows: "COM*"  Linux: "/dev/ttyUSB*"
MotorControl motor(port_name, 921600, 0x01);   // Params: serial port path (string), baud rate (uint32_t), actuator id (0x05060100)
MotorStatus status;
int main()
{
    motor.mode_selection(Mode::CURRENT_MODE, 10, 10, 10);
    
    motor.write_current_pid(0.02, 0.002);
    Sleep(300);
    motor.write_current(1000);
    auto start_time = chrono::steady_clock::now();
    while(1)
    {
        status = motor.get_motor_status({ 0xB1 });
        cout << "电流环P:0.02 I:0.002 电流: " << status.current_value << endl;
        auto current_time = chrono::steady_clock::now();
        double elapsed_time = chrono::duration<double>(current_time - start_time).count();
        if (elapsed_time >= 5.0) 
        {
            motor.write_current(0);
            break;
        }
    }
    
    Sleep(1000);
    
    motor.write_current_pid(0.0006, 0.0001);
    Sleep(300);
    motor.write_current(1000);
    start_time = chrono::steady_clock::now();
    while (1)
    {
        status = motor.get_motor_status({ 0xB1 });
        cout << " 电流环P:0.0006 I:0.0001 电流: " << status.current_value << endl;
        auto current_time = chrono::steady_clock::now();
        double elapsed_time = chrono::duration<double>(current_time - start_time).count();
        if (elapsed_time >= 5.0)
        {
            motor.write_current(0);
            break;
        }
    }
    Sleep(300);
    motor.reset();
}

Python:

import time
import matplotlib.pyplot as plt
from motor_control import *

id = [0x01]
port_name = "COM3"
motor = MotorControl(port_name, id, 921600)
mode_selection(motor, CURRENT_MODE, 10, 10, 10)

current_pid_set(motor, [0.02], [0.002])
time.sleep(0.3)
write_current(motor, [1000])
current_time = time.time()  
while True:
    results = get_v_p_c_v(motor)
    print(f"ID:{results[0][0]}, 电流环P:0.02 I:0.002 电流: {results[0][3]}")
    if (time.time() - current_time >= 5):
        write_current(motor, [0])
        break

time.sleep(1)

current_pid_set(motor, [0.0006], [0.0001])
time.sleep(0.3)
write_current(motor, [1000])
current_time = time.time()
while True:
    results = get_v_p_c_v(motor)
    print(f"ID:{results[0][0]}, 电流环P:0.0006 I:0.0001 电流: {results[0][3]}")
    if (time.time() - current_time >= 5):
        write_current(motor, [0])
        break
        
time.sleep(1)
reset(motor)

实时修改速度环PI

C++:

#include <motor_control.h>
string port_name = "COM3";                     // Windows: "COM*"  Linux: "/dev/ttyUSB*"
MotorControl motor(port_name, 921600, 0x01);   // Params: serial port path (string), baud rate (uint32_t), actuator id (0x05060100)
MotorStatus status;
int main()
{
    motor.mode_selection(Mode::PROFILE_VELOCITY_MODE, 10, 10, 10);
    motor.write_velocity_pid(25, 0.6);
    Sleep(300);
    motor.write_profile_velocity(3000, 500);
    auto start_time = chrono::steady_clock::now();
    while(1)
    {
        status = motor.get_motor_status({ 0xB1 });
        cout << " 速度环P为25 I为0.6 速度: " << status.velocity_value << endl;
        auto current_time = chrono::steady_clock::now();
        double elapsed_time = chrono::duration<double>(current_time - start_time).count();
        if (elapsed_time >= 5.0) 
        {
            motor.write_profile_velocity(3000, 0);
            break;
        }
    }
    Sleep(300);
    motor.write_velocity_pid(100, 2.4);
    Sleep(1000);
    motor.write_profile_velocity(3000, 500);
    start_time = chrono::steady_clock::now();
    while (1)
    {
        status = motor.get_motor_status({ 0xB1 });
        cout << " 速度环P为100 I为2.4 速度: " << status.velocity_value<< endl;
        auto current_time = chrono::steady_clock::now();
        double elapsed_time = chrono::duration<double>(current_time - start_time).count();
        if (elapsed_time >= 5.0) 
        {
            motor.write_profile_velocity(3000, 0);
            break;
        }
    }

    Sleep(300);
    motor.reset();
}

Python:

import time
import matplotlib.pyplot as plt
from motor_control import *

id = [0x01]
port_name = "COM3"
motor = MotorControl(port_name, id, 921600)
mode_selection(motor, PROFILE_VELOCITY_MODE, 10, 10, 10)

velocity_pid_set(motor, [25], [0.6])
time.sleep(0.3)
write_profile_velocity(motor, [3000], [500])
current_time = time.time()  
while True:
    results = get_v_p_c_v(motor)
    print(f"ID:{results[0][0]}, 速度环P为25 I为0.6 速度: {results[0][4]}")
    if (time.time() - current_time >= 5):
        write_profile_velocity(motor, [3000], [0])
        break

time.sleep(2)
velocity_pid_set(motor, [100], [2.4])
time.sleep(0.3)
write_profile_velocity(motor, [3000], [500])

current_time = time.time()
while True:
    results = get_v_p_c_v(motor)
    print(f"ID:{results[0][0]}, 速度环P为100 I为2.4 速度: {results[0][4]}")
    if (time.time() - current_time >= 5):
        write_profile_velocity(motor, [3000], [0])
        break

实时修改位置环PD

C++:

#include <motor_control.h>
string port_name = "COM3";                     // Windows: "COM*"  Linux: "/dev/ttyUSB*"
MotorControl motor(port_name, 921600, 0x01);   // Params: serial port path (string), baud rate (uint32_t), actuator id (0x05060100)
MotorStatus status;
int main()
{
    motor.mode_selection(Mode::PROFILE_POSITION_MODE, 10, 10, 10);
    motor.write_position_pid(0.4, 0.0);
    Sleep(300);
    motor.write_profile_position(3000, 2000, 65535);
    auto start_time = chrono::steady_clock::now();
    while(1)
    {
        status = motor.get_motor_status({ 0xB1 });
        cout << "位置环P为0.4 d为0 速度：" << status.velocity_value  << endl;
        auto current_time = chrono::steady_clock::now();
        double elapsed_time = chrono::duration<double>(current_time - start_time).count();
        if (elapsed_time >= 8.0) 
        {
            motor.write_profile_position(3000, 2000, 0);
            break;
        }
    }
    
    Sleep(8000);
    
    motor.write_position_pid(1.6, 0.0);
    motor.write_profile_position(3000, 2000, 65535);
    start_time = chrono::steady_clock::now();
    while (1)
    {
        status = motor.get_motor_status({ 0xB1 });
        cout << "位置环P为1.6 d为0 速度：" << status.velocity_value  << endl;
        auto current_time = chrono::steady_clock::now();
        double elapsed_time = chrono::duration<double>(current_time - start_time).count();
        if (elapsed_time >= 8.0) 
        {
            motor.write_profile_position(3000, 2000, 0);
            break;
        }
    }
    Sleep(8000);
    motor.reset();
}

Python:

from motor_control import *
id = [0x01]
port_name = "COM3"
motor = MotorControl(port_name, id, 921600)
mode_selection(motor, PROFILE_POSITION_MODE, 10, 10, 10)

position_pid_set(motor, [0.4], [0])
time.sleep(0.3)
write_profile_position(motor, [3000], [2000], [65535])
current_time = time.time()  
while True:
    results = get_v_p_c_v(motor)
    print(f"ID:{results[0][0]}, 位置环P为0.4 d为0 位置: {results[0][4]}")
    if (time.time() - current_time >= 8):
        write_profile_position(motor, [3000], [2000], [0])
        break

time.sleep(8)

position_pid_set(motor, [1.6], [0])
time.sleep(0.3)
write_profile_position(motor, [3000], [2000], [65535])
current_time = time.time()
while True:
    results = get_v_p_c_v(motor)
    print(f"ID:{results[0][0]}, 位置环P为1.6 d为0 速度: {results[0][4]}")
    if (time.time() - current_time >=8):
        write_profile_position(motor, [3000], [2000], [0])
        break
time.sleep(8)
reset(motor)