Joy-it Roboter-Arm-Bausatz User guide

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Robot-Arm-Assembly-Kit

Calibration

Robot 02

Release 18.08.2017 Copyright by Joy-IT 1

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Index

1. Introducon & general Informaons

2. Connecng the motors & using the right values

3. Code to calibrate the motors

4. Easy calibraon with the calibraon tool

5. Service & Contact

Robot 02 - Calibration

Release 18.08.2017 Copyright by Joy-IT 2

Robot 02 - Calibration

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1. Introduction & general informations

Dear customer,

to ensure you a perfect product, it is necessary to calibrate the servo-motors in its posion before you
assemble them.

This is necessary due to its technical construcon. The motors are limited in their operang angle.
Therefore it is necessary to dene a preset posion before you assemble the motors into the robot arm.
This ensures that you are able to use the maximum range of moon and avoids unexpected problems

2. Connecting the motors & using the right values

For a perfect servo-motor calibraon, these should be posioned on a value of 1500.
The working angle of the last servo (the claw) has a small deviaon to the working angle of the other
motors.
Therefore this motor should be set to 1600.
Connect the motors to the channels 0-4 of the motor-control-unit.
The claw-motor should be connect to channel 5.

Connect all motors to the control-unit as seen in the image below.
Warning! You should only connect the motors when there is a controller-joysck-unit connected to the
device to avoid unexpected movements.

Release 18.08.2017 Copyright by Joy-IT 3

Robot 02 - Calibration

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3. Code to calibrate the motors

You can calibrate the motors with the following code.
Please note that you need to connect the motor, which you are going to use for the claw, to channel 5.
Read the previous chapter for more informaons.

This code requires the installaon of our modied librarie.
If you haven‘t installed it yet, you can download the librarie here.
Copie the folder to your Raspberry Pi, navigate into the folder and install the librarie with the following
command:

sudo python setup.py install

Now you need to create a new le with the following command:

sudo nano calibrate.py

You can now write the code from the next page to the le.

Release 18.08.2017 Copyright by Joy-IT 4

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from __future__ import division
import time
import Adafruit_PCA9685

# Initialise with alternative address

pwm = Adafruit_PCA9685.PCA9685(address=0x41)

# define the minimum & maximum pulselength

servo_min = 150 # Minimum pulselength
servo_max = 600 # Maximum pulselength

# Helper-function

def set_servo_pulse(channel, pulse):

pulse_length = 1000000
pulse_length /= 50
print('{0}us per period'.format(pulse_length))
pulse_length /= 4096
print('{0}us per bit'.format(pulse_length))
pulse *= 1000
print(pulse_length)
pulse /= pulse_length
print(pulse)
pulse = round(pulse)
print(pulse)
pulse = int(pulse)
print (pulse)
pwm.set_pwm(channel, 0, pulse)

# set frequency to 50 MHz

pwm.set_pwm_freq(50)

# Set Servo 0-4 to position 1500
# Set Servo 5 to position 1600

set_servo_pulse(0,1.5)
time.sleep(1.5)
set_servo_pulse(1,1.5)
time.sleep(1.5)
set_servo_pulse(2,1.5)
time.sleep(1.5)
set_servo_pulse(3,1.5)
time.sleep(1.5)
set_servo_pulse(4,1.5)
time.sleep(1.5)
set_servo_pulse(5,1.5)
time.sleep(1.5)

Robot 02 - Calibration

Release 18.08.2017 Copyright by Joy-IT 5

Robot 02 - Calibration

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You can save the le with the combinaon CTRL+O and leave it with CTRL+X.

Start the calibraon with the following command:

sudo python calibrate.py

4. Easy calibration with the calibration tool

You can also use the calibraon tool which is sold separately.
With this device you can calibrate your motors easy and quick without connecng it to your Raspberry Pi.

Release 18.08.2017 Copyright by Joy-IT 6

Robot 02 - Calibration

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7. Service & Contact

We also support you aer your purchase.

If there are any quesons le or if you encounter any problems, please feel free to contact us by mail,

phone or our cket-supportsystem.

E-Mail: [e-mail]

Ticket-System: hp://support.joy-it.net

Phone: [phone] – 66 (11- 18 Uhr an Werktagen)

For more informaons, visit our website

www.joy-it.net

Find latest downloads at

hp://downloads.joy-it.net

Declaration of conformity

As manufacturer we, the Joy-IT Europe GmbH, declare that our product Robot02 matches the essenal
requirements during the intended use:

EMV-Richtlinie 2014/30/EU RoHS-Richtlinie 2011/65/EU

You can request the detailed declaraon of conformity at the following address:
JOY-iT Europe GmbH , Pascalstr. 8, D-47506 Neukirchen-Vluyn or by mail [e-mail]

13.07.2017 Yue Yang director

Warning. This declaraon of conformity only applies for our delivered components of the kit.
The motors keep the condions of the EMV guideline during the use of the declared voltage.
By adding own parts, you become the manufacturer and need to ensure that your device matches the
regulaons.

Release 18.08.2017 Copyright by Joy-IT 7