Note

Hello, welcome to the SunFounder Raspberry Pi & Arduino & ESP32 Enthusiasts Community on Facebook! Dive deeper into Raspberry Pi, Arduino, and ESP32 with fellow enthusiasts.

Why Join?

  • Expert Support: Solve post-sale issues and technical challenges with help from our community and team.

  • Learn & Share: Exchange tips and tutorials to enhance your skills.

  • Exclusive Previews: Get early access to new product announcements and sneak peeks.

  • Special Discounts: Enjoy exclusive discounts on our newest products.

  • Festive Promotions and Giveaways: Take part in giveaways and holiday promotions.

👉 Ready to explore and create with us? Click [here] and join today!

7.11 Somatosensory Controller

If you watch a lot of robot movies, you’ve probably seen images like this. The protagonist turned his wrist and the giant robot followed; the protagonist shakes his fist, and the robot follows, which is very cool.

The use of this technology is already common in universities and research institutes, and the arrival of 5G will greatly expand its application areas. “Surgical robot da Vinci” remote surgery medical is a typical example.

A robotic system of this type is typically composed of two modules: a human motion capture module and a robotic arm actuation module (some application scenarios also include a data communication module).

The MPU6050 is used here to implement human motion capture (by mounting it on a glove) and the servo is used to represent robotic arm motion.

Required Components

In this project, we need the following components.

It’s definitely convenient to buy a whole kit, here’s the link:

Name

ITEMS IN THIS KIT

LINK

Kepler Kit

450+

Kepler Kit

You can also buy them separately from the links below.

SN

COMPONENT

QUANTITY

LINK

1

Raspberry Pi Pico W

1

BUY

2

Micro USB Cable

1

3

Breadboard

1

BUY

4

Jumper Wires

Several

BUY

5

MPU6050 Module

1

6

Servo

1

BUY

Schematic

sch_somato

The MPU6050 calculates the attitude angle based on the acceleration values in each direction.

The program will control the servo to make the corresponding deflection angle as the attitude angle changes.

Wiring

wiring_somatosensory_controller

Code

Note

  • Open the 7.11_somatosensory_controller.py file under the path of kepler-kit-main/micropython or copy this code into Thonny, then click “Run Current Script” or simply press F5 to run it.

  • Don’t forget to click on the “MicroPython (Raspberry Pi Pico)” interpreter in the bottom right corner.

  • For detailed tutorials, please refer to Open and Run Code Directly.

  • Here you need to use the imu.py and vector3d.py, please check if it has been uploaded to Pico W, for a detailed tutorial refer to 1.4 Upload the Libraries to Pico.

from imu import MPU6050
from machine import I2C, Pin
import time
import math

# mpu6050
i2c = I2C(1, sda=Pin(6), scl=Pin(7), freq=400000)
mpu = MPU6050(i2c)

# servo
servo = machine.PWM(machine.Pin(15))
servo.freq(50)


def interval_mapping(x, in_min, in_max, out_min, out_max):
    return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min



# get rotary angle
def dist(a,b):
    return math.sqrt((a*a)+(b*b))

def get_y_rotation(x,y,z):
    radians = math.atan2(x, dist(y,z))
    return -math.degrees(radians)

def get_x_rotation(x,y,z):
    radians = math.atan2(y, dist(x,z))
    return math.degrees(radians)

# servo work
def servo_write(pin,angle):
    pulse_width=interval_mapping(angle, 0, 180, 0.5,2.5)
    duty=int(interval_mapping(pulse_width, 0, 20, 0,65535))
    pin.duty_u16(duty)

times=25
while True:
    total=0
    for i in range(times):
        angle=get_y_rotation(mpu.accel.x, mpu.accel.y, mpu.accel.z) #get rotation value
        total+=angle
    average_angle=int(total/times) # make the value smooth
    servo_write(servo,interval_mapping(average_angle,-90,90,0,180))

As soon as the program runs, the servo will turn left and right as you tilt the MPU6050 (or turn your wrist if it is mounted on a glove).