phospho starter pack documentation

phosphobot provides a simple API to control the robot arm. You can use it to move the robot arm, open or close the gripper, and more. All code examples can be found in our open source repo here.

Square movement

Show code - python implementation

This implementation uses the /move/relative endpoint to move the robot in a square. We simply indicate where we want to move the robot relative to its current position.

square.py

import time
import requests

# Configurations
PI_IP: str = "127.0.0.1"
PI_PORT: int = 80
NUMBER_OF_SQUARES: int = 100


# Function to call the API
def call_to_api(endpoint: str, data: dict = {}):
    response = requests.post(f"http://{PI_IP}:{PI_PORT}/move/{endpoint}", json=data)
    return response.json()


# Example code to move the robot in a square of 4 cm x 4 cm
# 1 - Initialize the robot
call_to_api("init")
print("Initializing robot")
time.sleep(2)

# We move it to the top left corner of the square
call_to_api(
    "relative", {"x": 0, "y": -3, "z": 0.03, "rx": 0, "ry": 0, "rz": 0, "open": 0}
)
print("Moving to top left corner")
time.sleep(0.2)

# With the move relative endpoint, we can move relative to its current position
# 2 - We make the robot follow a 3 cm x 3 cm square
for _ in range(NUMBER_OF_SQUARES):
    # Move to the top right corner
    call_to_api(
        "relative", {"x": 0, "y": 3, "z": 0, "rx": 0, "ry": 0, "rz": 0, "open": 0}
    )
    print("Moving to top right corner")
    time.sleep(0.2)

    # Move to the bottom right corner
    call_to_api(
        "relative", {"x": 0, "y": 0, "z": -3, "rx": 0, "ry": 0, "rz": 0, "open": 0}
    )
    print("Moving to bottom right corner")
    time.sleep(0.2)

    # Move to the bottom left corner
    call_to_api(
        "relative", {"x": 0, "y": -3, "z": 0, "rx": 0, "ry": 0, "rz": 0, "open": 0}
    )
    print("Moving to bottom left corner")
    time.sleep(0.2)

    # Move to the top left corner
    call_to_api(
        "relative", {"x": 0, "y": 0, "z": 3, "rx": 0, "ry": 0, "rz": 0, "open": 0}
    )
    print("Moving to top left corner")
    time.sleep(0.2)

Circle movement

Slow

Show code - python implementation

Since it’s harder to control the robot’s position using relative movements to create a circle, we use the absolute movement instead. We calculate the position of the robot in the circle using the sin and cos functions to create a circular motion.

circle_slow.py

import math
import time
import requests

# Configurations
PI_IP: str = "127.0.0.1"
PI_PORT: int = 80
NUMBER_OF_STEPS: int = 10
NUMBER_OF_CIRCLES: int = 15


# Function to call the API
def call_to_api(endpoint: str, data: dict = {}):
    response = requests.post(f"http://{PI_IP}:{PI_PORT}/move/{endpoint}", json=data)
    return response.json()


# Example code to move the robot in a circle
# 1 - Initialize the robot
call_to_api("init")
print("Initializing robot")
time.sleep(2)

# With the move absolute endpoint, we can move the robot in an absolute position
# 2 - We move the robot in a circle with a diameter of 4 cm
for _ in range(NUMBER_OF_CIRCLES):
    for step in range(NUMBER_OF_STEPS):
        position_y: float = 4 * math.sin(2 * math.pi * step / NUMBER_OF_STEPS) 
        position_z: float = 4 * math.cos(2 * math.pi * step / NUMBER_OF_STEPS) 
        call_to_api(
            "absolute",
            {
                "x": 0,
                "y": position_y,
                "z": position_z,
                "rx": 0,
                "ry": 0,
                "rz": 0,
                "open": 0,
            },
        )
        print(f"Step {step} - x: 0, y: {position_y}, z: {position_z}")
        time.sleep(0.03)

Fast

Show code - python implementation

To quicken the robots movements, we lower the number of steps in the circle. We also increase the sleep time between each step to avoid the robot moving too fast.

circle_fast.py

import math
import time
import requests

# Configurations
PI_IP: str = "127.0.0.1"
PI_PORT: int = 80
NUMBER_OF_STEPS: int = 10
NUMBER_OF_CIRCLES: int = 15


# Function to call the API
def call_to_api(endpoint: str, data: dict = {}):
    response = requests.post(f"http://{PI_IP}:{PI_PORT}/move/{endpoint}", json=data)
    return response.json()


# Example code to move the robot in a circle
# 1 - Initialize the robot
call_to_api("init")
print("Initializing robot")
time.sleep(2)

# With the move absolute endpoint, we can move the robot in an absolute position
# 2 - We move the robot in a circle with a diameter of 4 cm
for _ in range(NUMBER_OF_CIRCLES):
    for step in range(NUMBER_OF_STEPS):
        position_y: float = 4 * math.sin(2 * math.pi * step / NUMBER_OF_STEPS) 
        position_z: float = 4 * math.cos(2 * math.pi * step / NUMBER_OF_STEPS) 
        call_to_api(
            "absolute",
            {
                "x": 0,
                "y": position_y,
                "z": position_z,
                "rx": 0,
                "ry": 0,
                "rz": 0,
                "open": 0,
            },
        )
        print(f"Step {step} - x: 0, y: {position_y}, z: {position_z}")
        time.sleep(0.2)

​Square movement

​Circle movement

​Slow

​Fast

Square movement

Circle movement

Slow

Fast