KOI AI 氣墊球

AI氣墊球機械人會自動追蹤圓球並防守龍門，結合了人工智能技術和玩樂元素。

學生可以透過與KOI人工智能競技，從遊戲中了解現今機器視覺的原理，激發對人工智能的興趣。

更高階的學生更可以透過Python編程編寫自己的AI氣墊球機械人。

搭建說明書

下載說明書

接線圖

KOI接線圖

舵機接線圖

套件內容

1. Robotbit EDU連底座 *1

2. KOI AI鏡頭 *1

3. GeekServo 2KG灰色舵機 *2

4. 積木件 *1套

5. 氣墊球機 *1

6. KOI連接線 *1

7. 1m USB線 *1

8. 18650鋰電池 *1

額外所需物資

• USB移動式電源 或

• USB 5V充電器

操作教學

打開Robotbit電源後，KOI會追蹤並阻擋紅色球片。

示範短片

參考程式

出廠時KOI已經預載參考程式，如有需要請用KittenCode載入此py檔上載至KOI。

8KB

main.py

import sensor, image, time, lcd, utime
import math, ustruct
from maix import KPU, GPIO, I2S
from machine import UART, I2C

from fpioa_manager import fm

import gc

grid = [
    (56,74),(96,74),(137,72),(179,70),(220,68),(262,67),
    (52,113),(94,116),(136,112),(179,109),(222,107),(264,104),
    (51,157),(93,156),(139,154),(181,151),(227,150),(269,147),
]

PCA9685_ADDRESS    = 0x40
MODE1              = 0x00
MODE2              = 0x01
SUBADR1            = 0x02
SUBADR2            = 0x03
SUBADR3            = 0x04
PRESCALE           = 0xFE
LED0_ON_L          = 0x06
LED0_ON_H          = 0x07
LED0_OFF_L         = 0x08
LED0_OFF_H         = 0x09
ALL_LED_ON_L       = 0xFA
ALL_LED_ON_H       = 0xFB
ALL_LED_OFF_L      = 0xFC
ALL_LED_OFF_H      = 0xFD

S1 = 0x1
S2 = 0x2
S3 = 0x3
S4 = 0x4
S5 = 0x5
S6 = 0x6
S7 = 0x7
S8 = 0x8

RESTART            = 0x80
SLEEP              = 0x10
ALLCALL            = 0x01
INVRT              = 0x10
OUTDRV             = 0x04
RESET              = 0x00

positions = [
    [240, 195], [235, 175], [220, 155], [210, 135], [190, 125], [160, 115],
    [260, 190], [250, 165], [235, 145], [220, 125], [195, 105], [170, 95],
    [285, 190], [275, 170], [250, 140], [220, 105], [195, 85], [170, 70]
]


class RobotBit:

    def __init__(self):
        self.address = PCA9685_ADDRESS
        self.i2c = I2C(I2C.I2C0, freq=400000, scl=17, sda=14, addr_size=7)
        self.i2c.writeto(self.address, bytearray([MODE1, RESET])) # reset not sure if needed but other libraries do it
        self.i2c.writeto(self.address, bytearray([MODE1, RESET]))
        self.i2c.writeto(self.address, bytearray([MODE2, OUTDRV]))
        self.i2c.writeto(self.address, bytearray([MODE1, ALLCALL]))
        time.sleep_ms(5)
        mode1 = self.i2c.readfrom_mem(self.address, MODE1, 1)[0]
        mode1 = mode1 & ~SLEEP  # wake up (reset sleep)
        self.i2c.writeto(self.address, bytearray([MODE1, mode1]))
        time.sleep_ms(5)
        self.set_pwm_freq(50)
        self.inited = True
    
    def set_pwm_freq(self, freq_hz):
        """Set the PWM frequency to the provided value in hertz."""
        prescaleval = 25000000.0    # 25MHz
        prescaleval /= 4096.0       # 12-bit
        prescaleval /= float(freq_hz)
        prescaleval -= 1.0
        prescale = int(math.floor(prescaleval + 0.5))
        oldmode = self.i2c.readfrom_mem(self.address, MODE1, 1)[0]
        newmode = (oldmode & 0x7F) | 0x10    # sleep
        self.i2c.writeto(self.address, bytearray([MODE1, newmode]))
        self.i2c.writeto(self.address, bytearray([PRESCALE, prescale]))
        self.i2c.writeto(self.address, bytearray([MODE1, oldmode]))
        time.sleep_ms(5)
        self.i2c.writeto(self.address, bytearray([MODE1, oldmode | 0x80]))


    def set_pwm(self, channel, on, off):
        """Sets a single PWM channel."""
        if not self.inited:
            self.initRobotBit()
        if on is None or off is None:
            data = self.i2c.mem_read(4, self.address, LED0_ON_L+4*channel)
            return ustruct.unpack('<HH', data)
        self.i2c.writeto(self.address, bytearray([LED0_ON_L+4*channel, on & 0xFF]))
        self.i2c.writeto(self.address, bytearray([LED0_ON_H+4*channel, on >> 8]))
        self.i2c.writeto(self.address, bytearray([LED0_OFF_L+4*channel, off & 0xFF]))
        self.i2c.writeto(self.address, bytearray([LED0_OFF_H+4*channel, off >> 8]))

    def geekServo(self, index, degree):
        # 50hz: 25,000 us
        # 500~2650us->0~360
        # v_us = degree * 50 / 9 +500
        v_us = 200/36*degree + 500  # calibrated
        value = int(v_us*4096/20000)
        self.set_pwm(index+7, 0, value)


class AirHockey:

    def __init__(self):
        self.thresholdMap = {
            'red': [30,100,15,127,15,127],
            'blue': [0,50,-64,64,-127,-20],
            'red2': [29,98,-9,57,0,47]
        }
        sensor.reset()
        sensor.set_pixformat(sensor.RGB565)
        sensor.set_framesize(sensor.QVGA)
        lcd.init()
        lcd.rotation(0)
        lcd.clear()
        sensor.set_vflip(True)
        sensor.run(1)
        sensor.skip_frames(time = 2000)
        self.displayGrid()
        self.cachedPosition = []
        self.t0 = time.ticks_ms()
        self.lastIndex = -1
        self.robo = RobotBit()

    def displayGrid(self):
        self.img = sensor.snapshot()
        for i in range(len(grid)):
            self.img.draw_cross(grid[i][0],grid[i][1],5,color=(0,255,0))
        lcd.display(self.img)

    def colorCalibrate(self, key, r=[(320//2)-(50//2), (240//2)-(50//2), 50, 50]):
        for i in range(60):
            self.img = sensor.snapshot()
            self.img.draw_string(40, 0, "put the color\nin the rect", scale=2,color=(0,255,0))
            self.img.draw_rectangle(r)
            lcd.display(self.img)

        threshold = [50, 50, 0, 0, 0, 0] # Middle L, A, B values.
        for i in range(60):
            self.img = sensor.snapshot()
            self.img.draw_string(40, 0, "be learning...", scale=2,color=(0,255,0))
            hist = self.img.get_histogram(roi=r)
            lo = hist.get_percentile(0.01) # Get the CDF of the histogram at the 1% range (ADJUST AS NECESSARY)!
            hi = hist.get_percentile(0.99) # Get the CDF of the histogram at the 99% range (ADJUST AS NECESSARY)!
            # Average in percentile values.
            threshold[0] = (threshold[0] + lo.l_value()) // 2
            threshold[1] = (threshold[1] + hi.l_value()) // 2
            threshold[2] = (threshold[2] + lo.a_value()) // 2
            threshold[3] = (threshold[3] + hi.a_value()) // 2
            threshold[4] = (threshold[4] + lo.b_value()) // 2
            threshold[5] = (threshold[5] + hi.b_value()) // 2
            for blob in self.img.find_blobs([threshold], pixels_threshold=100, area_threshold=100, merge=True):
                self.img.draw_rectangle(blob.rect())
                self.img.draw_cross(blob.cx(), blob.cy())
                self.img.draw_rectangle(r)
            lcd.display(self.img)
        self.thresholdMap[key] = threshold
        print(threshold)
    

    def getPosition(self, x, y):
        # calculate the closest grid index
        minDist = 100000
        minIndex = -1
        for i in range(len(grid)):
            dist = (grid[i][0]-x)**2 + (grid[i][1]-y)**2
            if dist < minDist:
                minDist = dist
                minIndex = i
        return minIndex
    

    def setPositon(self, index):
        pos = positions[index]
        self.robo.geekServo(S8, pos[1])
        self.robo.geekServo(S7, pos[0])
        
    def colorTrack(self,key='red'):
        cx=-1
        cy=-1
        maxArea = 0
        #([self.thresholdMap[key]], pixels_threshold=100, area_threshold=100, merge=True, margin=10)
        for blob in self.img.find_blobs([self.thresholdMap[key]], pixels_threshold=200, area_threshold=200, merge=True, margin=10):
            self.img.draw_rectangle(blob.rect())
            self.img.draw_cross(blob.cx(), blob.cy())
            cx = blob.cx()
            cy = blob.cy()
            if blob.rect()[2] * blob.rect()[3] > maxArea:
                maxArea = blob.rect()[2] * blob.rect()[3]
        return (cx, cy)

    def tick(self):
        self.img = sensor.snapshot()
        (rx, ry) = self.colorTrack('red')
        if rx == -1:
            self.cachedPosition = []
            lcd.display(self.img)
            self.setPositon(8)
            return
        index = self.getPosition(rx, ry)
        self.img.draw_cross(grid[index][0],grid[index][1],5,color=(0,255,0))
        print(index)
        # print history lines
        for i in range(len(self.cachedPosition)):
            self.img.draw_cross(self.cachedPosition[i][0], self.cachedPosition[i][1],color=(0,100,200))
        lcd.display(self.img)
        self.setPositon(index)
        self.cachedPosition.append((rx,ry))
        if len(self.cachedPosition) > 10:
            self.cachedPosition.pop(0)

    def run(self):
        while True:
            self.tick()
            time.sleep_ms(50)
            gc.collect()


ak = AirHockey()
#ak.colorCalibrate(key='red2')
ak.run()

舵機校正