Delta Robot Design and Development

อาจารย์ที่ปรึกษาโครงงาน ผู้ช่วยศาสตราจารย์ ดร.กิตติพงษ์ เยาวาจา
Asst.Prof.Kittipong Yaovaja

Suebsakul Kamlai 6230305089

Koranit Pundee 6230340011

Chapter 1

Introduction

Background and significance of the problem

Intelligent robots are innovations that play a huge role in industrial plants both domestically and internationally. In addition to industrial applications, there are also medical, research, household, and other applications that facilitate human labor. Because in addition to the robot working continuously, it also has speed and accuracy in working as well. Including dangers that can happen to humans or work areas that are risky to humans.

Types of robots.
Fixed robots: These robots are designed to operate in a fixed position and do not move from their location. They are typically used for tasks that require precision, such as assembly or inspection, and are often mounted on a fixed base or arm.

Figure 1 Fixed robots

Mobile robots: These robots are designed to move around and navigate their environment. They can be further classified into various subcategories, depending on their modes of locomotion, such as wheeled robots, legged robots, aerial robots, and underwater robots. Mobile robots are used in a wide range of applications, such as logistics, search and rescue, environmental monitoring, and agriculture.

Figure 2 Mobile robots

Both fixed and mobile robots have their advantages and limitations, and the choice of robot type depends on the specific application requirements. Fixed robots are ideal for tasks that require high precision and stability, while mobile robots are ideal for tasks that require flexibility, adaptability, and autonomy.
The project maker, therefore, had the idea to design the Delta robot for useful use. with a robotic arm that can move to the desired position and efficient, accurate, and fast movement

Objective

– To study the designs and programs of delta robots.
-To study the application of the program used to design the motion control of the delta robot.
-To study the equations that will be used in the motion of the delta robot. and torque calculation of each motor

Scope of the project

-Plan and design a delta robot. Based on the senior’s old structure and the robot in the room used to do the project.
-Delta robot can move to different points. By entering the position values, points x, y, and z.
-The robot can move to pick up things.

Benefits received from doing the project

– Learn about delta robot design. and gear design to increase the lifting power of the motor
-Learn how to calculate the torque of each motor to calculate the weight that each motor can lift and how much weight can be lifted when assembled into a robot.
-Learned to design a computer program for instructing the robot to move and be able to move to the predetermined coordinates.
-Learned about the kinematic equations to be used in delta robot motion.
-Learned about connecting various electrical circuits. used with robots.

Operation plan

Before midterm
Mechanic
     – Study and collect information related to the creation of Delta robots and study the problems of the old robots from senior reports.
     -Robot design using Solidworks program.
     -Study and increase the torque to the motor. By designing and building Planetary Gear.
     -List of equipment to be used to build a delta robot.
     – Motor Torque Test
     -Test and fix the size of the robot. and equipment used to create robots
     -simulating the old robot with MATLAB program.
     -Study the inverse kinematics and forward kinematics of Delta robots.
     -Design and fix the installation model of the 4th axis
     – Experiment with controlling the motor through the NI board. And encoder
     – Design the installation of the sensor and using a 3D printer, create a mount for the motor.
     – Design and print support of rod joint bearing
After midterm

Mechanic Improvements and Fixes
-Wiring and installation of various devices of the Delta robot
Program
     -Motor test with gear and encoder After being assembled into the delta robotic arm.
     -Write a program that will be used to control the Delta robot with the LabView program.
          – Manual robot control
         -Auto robot control

Chapter 2

Theory and literature review

Related literature

Delta robots were first developed in the early 1980s by Reymond Clavel, a professor at the Ecole Polytechnique Federale de Lausanne (EPFL) in Switzerland. Clavel was inspired by the parallel-linkage Stewart platform, which had been developed in the 1960s for use in flight simulators, and set out to create a similar mechanism that could be used for high-speed pick-and-place operations in the food industry.

After several years of research and development, Clavel and his team created the prototype of the Delta robot in 1985. The robot consisted of three arms connected to a central platform, which was suspended from a frame by three cables. By controlling the length and tension of the cables, the robot could move the platform in three dimensions with a high degree of accuracy and speed.

The delta robot quickly proved to be a game-changer in the food industry, where it was used to automate the packaging of products such as chocolates and candies. Its speed and precision allowed manufacturers to increase their throughput while maintaining product quality, and it soon became a standard piece of equipment in many food factories around the world.

Over the years, the design of the Delta robot has been refined and adapted for use in a wide range of industries, including electronics, pharmaceuticals, and automotive manufacturing. Today, it is recognized as one of the most versatile and reliable types of industrial robots and continues to be widely used in factories and production facilities around the world.

Figure 3 Reymond Clavel (left) with a Delta robot

Applications

delta robots are widely used in a variety of applications, including:

Pick-and-Place Operations: Delta robots are well-suited for picking up and moving objects quickly and accurately, making them ideal for pick-and-place operations in industries such as food, pharmaceuticals, and electronics.

Figure 4 Pick-and-Place

Assembly: Delta robots can be used for assembly tasks that require high speed and precision, such as assembling small electronic components.

Figure 5 Delta robot assembles parts

Link https://www.assemblymag.com/articles/92654-delta-robots-feed-need-for-speed

3D Printing: Delta robots can be used for 3D printing applications like printing complex geometries or printing with multiple materials.

Figure 6 3d printer with delta robot

Link https://roboticarts.wordpress.com/2013/04/04/delta-robot-completed-jeden/

Medical Applications: Delta robots can be used for medical applications, such as performing minimally invasive surgeries or handling laboratory samples.

Figure 7 Medical Applications: Delta robots

Link https://www.researchgate.net/figure/Fig-5-Delta-Robot-Used-in-Surgical-Applications-19_fig3_340137275

Overall, the speed, precision, and versatility of delta robots make them well-suited for a wide range of applications in manufacturing, packaging, inspection, and other industries.

Study and collect information related to the creation of Delta robots.

Figure 8 Gesture-controlled delta robot (LabVIEW + Kinect 2)

Link https://www.youtube.com/watch?v=9LXexNV_Uc4

Figure 9 Delta Robot Operation – MSc Project

Link https://www.youtube.com/watch?v=jZt6OtxTPb8

Figure 10 makes simple object tracking to pick & place products with Delta X Software

Link https://www.youtube.com/watch?v=b1SAMBCa1tE

Figure 11 delta robot based On Arduino

Link https://www.youtube.com/watch?v=IUnhXH0_Re4

Figure 12 Old robots from senior

Link https://gulfthai.com/?p=2509

Related theory

The mechanics and control of delta robots are two important aspects of their design and operation. Here is a brief overview of each:

Mechanics:

The mechanics of delta robots involve the study of the physical components and interactions of the robot, such as the joints, arms, and platform. The kinematics and dynamics of delta robots are key aspects of their mechanics. Kinematics involves the study of the motion of the robot’s joints and end effector, while dynamics involves the study of the forces acting on the robot’s components. The mechanics of delta robots are critical to ensuring that the robot is stable, accurate, and able to handle the loads required for its intended applications.

Figure 13 Mechanics of Delta robots

Link https://www.researchgate.net/figure/The-Delta-robot-construction_fig1_326571609

Where:
1- The driving motor arm coupling joint
2- Upper platform (basic triangle)
3- Driving arm (thing-road)
4- Parallelogram joint
5- Driving arm, parallelogram joint
6- Parallelogram arm (shin)
7- Lower platform (working triangle)
8- Tool

Stepper Motor

Figure 14 Stepper Motor

Stepper motors are DC motors that move in discrete steps. They have multiple coils that are organized in groups called “phases”. By energizing each phase in sequence, the motor will rotate, one step at a time.

Figure 15 Stepper motors move in discrete steps

Types Of stepper motors

There are three main types of stepper motors:

Permanent Magnet Stepper. PM steppers have rotors that are constructed with permanent magnets, which interact with the electromagnets of the stator to create rotation and torque. PM steppers usually have comparatively low power requirements and can produce more torque per unit of input power.

Variable Reluctance Stepper. VR stepper rotors are not built with permanent magnets. Rather, they are constructed with plain iron and resemble a gear, with protrusions or “teeth” around the circumference of the rotor. The teeth lead to VR steppers that have a very high degree of angular resolution; however, this accuracy usually comes at the expense of torque.

Hybrid Synchronous Stepper. HS stepper rotors use the best features of both PM and VR steppers. The rotor in an HS motor has a permanent magnet core, while the circumference is built from plain iron and has teeth. A hybrid synchronous motor, therefore, has both high angular resolution and high torque.

Motor torque calculation formula

Torque calculation of the motor

From Manual

Maximum Torque = 1.3 N.m / 1 ตัว

Figure 16 Characteristic of Velocity-Torque

Source: Manual Motor Sanmotion (Sanyodenki)

Planetary Gear

How to calculate gear ratio

Figure 17 planetary gear 4:1

Gear ratio It plays an important role in the selection of the gear because it affects two factors in terms of increased torque and reduced speed Therefore, it should be emphasized from the design stage In order to be able to use the GEAR box to its full potential. 
Gear ratio of reduction gear set It is the ratio of the instantaneous input speed to the output speed in the speed reducer. The general deceleration ratio is expressed as the ratio of input speed to output speed with “1” in the denominator. If the input speed is 1500r/min and the output speed is 25r/min, the deceleration ratio is: i = 60:1
The formula for calculating the gear ratio:
1. Gear ratio formula = input speed ÷ output speed. The ratio of connected input speed and output speed. If the input speed is 1500r/min and the output speed is 25r/min, the reduction ratio is: i =60 :1.
2. Calculation method of gear set: reduction ratio=number of driven gears ÷ number of driven gears. (If multi-stage gear reduction equal to the number of driven gears of all gears engaged ÷ the number of active gear teeth, then the result is multiplied
The gear ratio determines the output torque of the gear motor:
        The greater the gear ratio the output torque of the gear motor will also only more and the ability to support the weight of the workpiece will be greater

The reduction gear torque is calculated as follows:
Ratio Gear = Motor output rpm ÷ Reducer output rpm (“gear ratio” is also called “speed ratio”).
1. If the gear ratio and servo motor torque and utilization coefficient are known. and find the torque as follows:
Torque=1.27 * Ratio Gear (60:1) = 1.27*60 = 76.2 Nm.
Gear APEX coefficient is 92-97%, multiply by the calculated torque value 76.2* 97% = 73.91 Nm.
2. If the gear ratio and rotational speed of the servo motor are known, then the output speed can be found as follows:
The speed of Servo 3,000 rpm Gear ratio 60: 1 will be equal to 3,000 / 60 = 50 rpm and when connected to other devices to calculate the distance traveled May have to convert to choose the speed of revolutions per second, take 60 minutes to divide by the rpm obtained from the calculation.
50 rpm = 50/60   = 0.833 rps.

Controller

     A controller is a device or system that manages the behavior or operation of another device or system. Controllers are used in a wide variety of applications, from simple household appliances to complex industrial processes.
     In the context of automation and control systems, a controller typically refers to an electronic device or software program that monitors and regulates a system’s or process’s behavior. The controller receives inputs from sensors or other sources and uses these inputs to calculate the appropriate output signals to control the behavior of the system. The output signals may be used to activate or deactivate actuators, change the speed or direction of a motor, adjust the temperature of a heating or cooling system, or perform other actions that affect the behavior of the system.
     Controllers may be implemented using a variety of technologies, including microprocessors, programmable logic controllers (PLCs), and software-based control systems. They may also incorporate feedback mechanisms, such as sensors or other monitoring devices, to adjust the control algorithm based on the behavior of the system.
      Overall, a controller is an essential component of many automation and control systems, providing the intelligence and decision-making capability necessary to regulate the behavior of the system and achieve the desired results.

Ni myRIO

Figure 18 Ni myRIO board

Link https://www.ni.com/en-th/support/documentation/supplemental/13/ni-myrio-hardware-at-a-glance.html

NI myRIO is a revolutionary hardware/software platform that gives students the ability to “do engineering” and design real systems more quickly than ever before. Complete with the latest Zynq integrated system-on-a-chip (SoC) technology from Xilinx, the NI myRIO boasts a dual-core ARM® Cortex™-A9 processor, and an FPGA with 28,000 programmable logic cells, 10 analog inputs, 6 analog outputs, audio I/O channels, and up to 40 lines of digital input/output (DIO). Designed and priced for the academic user, NI myRIO also includes onboard WiFi, a three-axis accelerometer, and several programmable LEDs in a durable, enclosed form factor.

Figure 19 NI myRIO Front View

Figure 20 NI myRIO Back View

Figure 21 NI myRIO Expansion Port (MXP) Connectors

The default I/O configuration is shown. It is customizable with the NI LabVIEW FPGA Module. These are 0.1″ pitch dual-row 34-position (17 x 2) IDC connectors.

Figure 22 NI myRIO NI mini systems Port (MSP) Connector

The default I/O configuration is shown. It is customizable with LabVIEW FPGA.

Figure 23 NI myRIO Top View

Figure 24 NI myRIO Bottom View

Kinematics

Kinematics is the branch of classical mechanics that describes the motion of points, objects, and systems of groups of objects, without reference to the causes of motion (i.e., forces). The study of kinematics is often referred to as the “geometry of motion.”

Figure 25 Kinematics model of delta robot

Link https://www.researchgate.net/figure/A-kinematics-model-of-the-DELTA-robot_fig2_220061904

Forward Kinematics is a technique used in robotics to determine the position and orientation of the end-effector of a robot, given the joint angles and link lengths of the robot. In other words, it is the mathematical process of calculating the position and orientation of the end-effector of a robot, based on the angles of the joints between the links in the robot arm.

Inverse Kinematics is an important tool in robotics, as it enables robots to move to specific locations and orientations in their workspace. The process involves using a series of equations that relate the robot’s joint angles to the position and orientation of its end-effector. The equations used in Inverse Kinematics are typically more complex than those used in Forward Kinematics, due to the non-linear nature of the relationships between the joint angles and the end-effector position.

Delta robot kinematics

When one talks about industrial robots, most of people imagine robotic arms, or articulated robots, which are doing painting, welding, moving something, etc. But there is another type of robots: so-called parallel delta robot, which was invented in the early 80’s in Switzerland by professor Reymond Clavel. Below the original technical drawing from U.S. Patent 4,976,582 is shown, and two real industrial delta robots, one from ABB, and one from Fanuc.
The delta robot consists of two platforms: the upper one with three motors mounted on it, and smaller one with an end effector. The platforms are connected through three arms with parallelograms, the parallelograms restrain the orientation of the lower platform to be parallel to the working surface (table, conveyor belt, and so on). The motors set the position of the arms and, thereby, the XYZ position of the end effector, while the fourth motor is used for the rotation of the end effector. You can find a more detailed description of the delta robot design in the corresponding Wikipedia article.

Inverse Kinematics

The core advantage of delta robots is speed. When typical robot arm has to move not only payload, but also all servos in each joint, the only moving part of delta robot is its frame, which is usually made of lightweight composite materials. To get an evidence of delta robots outstanding abilities, take a look at this and this video. Due to its speed, delta robots are widely used in pick-n-place operations of relatively light objects (up to 1 kg).

Problem definition
If we want to build our own delta robot, we need to solve two problems. First, if we know the desired position of the end effector (for example, we want to catch pancake in the point with coordinates X, Y, Z), we need to determine the corresponding angles of each of three arms (joint angles) to set motors (and, thereby, the end effector) in proper position for picking. The process of such determining is known as inverse kinematics.
And, in the second place, if we know joint angles (for example, we’ve read the values of motor encoders), we need to determine the position of the end effector (e. g. to make some corrections of its current position). This is forward kinematics problem.
To be more formal, let’s look at the kinematic scheme of delta robot. The platforms are two equilateral triangles: the fixed one with motors is green, and the moving one with the end effector is pink. Joint angles are theta1, theta2 and theta3, and point E0 is the end effector position with coordinates (x0, y0, z0). To solve inverse kinematics problems, we have to create function with E0 coordinates (x0, y0, z0) as parameters which returns (theta1, theta2, theta3). Forward kinematics functions get (theta1, theta2, theta3) and returns (x0, y0, z0).

Figure 26 delta robot kinematic diagram

Link https://hypertriangle.com/~alex/delta-robot-tutorial/

In the following two paragraphs will come the theoretical part of delta robot kinematics. Those who don’t like mathematics and trigonometry may jump right to the practical part: sample programs written in C language. So, let’s start from
First, let’s determine some key parameters of our robot’s geometry. Let’s designate the side of the fixed triangle as f, the side of the end effector triangle as e, the length of the upper joint as rf, and the length of the parallelogram joint as re. These are physical parameters which are determined by design of your robot. The reference

frame will be chosen with the origin at the center of symmetry of the fixed triangle, as shown below, so z-coordinate of the end effector will always be negative.

Figure 27 determine some key parameters of the geometry of the robot.

Link https://hypertriangle.com/~alex/delta-robot-tutorial/

Because of robot’s design joint F1J1 (see fig. below) can only rotate in YZ plane, forming circle with center in point F1 and radius rf. As opposed to F1, J1 and E1 are so-called universal joints, which means that E1J1 can rotate freely relatively to E1, forming sphere with center in point E1 and radius re.

Figure 28 create a circle centered on F1.

Link https://hypertriangle.com/~alex/delta-robot-tutorial/

Intersection of this sphere and YZ plane is a circle with center in point E’1 and radius E’1J1, where E’1 is the projection of the point E1 on YZ plane. The point J1 can be found now as intersection of to circles of known radius with centers in E’1 and F1 (we should choose only one intersection point with smaller Y-coordinate). And if we know J1, we can calculate theta1 angle.

Below you can find corresponding equations and the YZ plane view:

Figure 29 YZ plane view

Link https://hypertriangle.com/~alex/delta-robot-tutorial/

Figure 30 related equations

Such algebraic simplicity follows from good choice of reference frame: joint F1J1 moving in YZ plane only, so we cat completely omit X coordinate. To take this advantage for the remaining angles theta2 and theta3, we should use the symmetry of delta robot. First, let’s rotate coordinate system in XY plane around Z-axis through angle of 120 degrees counterclockwise, as it is shown below.

Figure 31 Rotate the coordinate system in the XY plane around the Z axis through an angle of 120 degrees counterclockwise.

We’ve got a new reference frame X’Y’Z’, and it this frame we can find angle theta2 using the same algorithm that we used to find theta1. The only change is that we need to determine new coordinates x’0 and y’0 for the point E0, which can be easily done using corresponding rotation matrix. To find angle theta3 we have to rotate reference frame clockwise. This idea is used in the coded example below: I have one function which calculates angle theta for YZ plane only, and call this function three times for each angle and each reference frame.

Forward kinematics
Now the three joint angles theta1, theta2 and theta3 are given, and we need to find the coordinates (x0, y0, z0) of end effector point E0.
As we know angles theta, we can easily find coordinates of points J1, J2 and J3 (see fig. below). Joints J1E1, J2E2 and J3E3 can freely rotate around points J1, J2 and J3 respectively, forming three spheres with radius re.

Figure 32 Find the coordinates of points J1, J2 and J3.

Now let’s do the following: move the centers of the spheres from points J1, J2 and J3 to the points J’1, J’2 and J’3 using transition vectors E1E0, E2E0 and E3E0 respectively. After this transition all three spheres will intersect in one point: E0, as it is shown in fig. below:

Figure 33 Move the center of the sphere from J1, J2, and J3 to J’1, J’2, and J’3.

So, to find coordinates (x0, y0, z0) of point E0, we need to solve set of three equations like (x-xj)^2+(y-yj)^2+(z-zj)^2 = re^2, where coordinates of sphere centers (xj, yj, zj) and radius re are known.

First, let’s find coordinates of points J’1, J’2, J’3:

Figure 34 Find the coordinates of points J’1, J’2, J’3

In the following equations I’ll designate coordinates of points J1, J2, J3 as (x1, y1, z1), (x2, y2, z2) and (x3, y3, z3). Please note that x0=0. Here are equations of three spheres:

Figure 35 Equation of three spheres

Finally, we need to solve this quadric equation and find z0 (we should choose the smallest negative equation root), and then calculate x0 and y0 from eq.

Sample programs
The following code is written in C, all variable names correspond to designations I’ve used above. Angles theta1, theta2 and theta3 are in degrees. You can freely use this code in your applications.

Compare accuracy (Inverse Kinematics)

Figure 36 Calculate in labview program compared to calculate on the web.

Compare accuracy (Forward Kinematics)

Figure 37 Calculate in labview program compared to calculate on the web.

Figure 38 Calculate in labview program compared to calculate on the web.

Control: The control of delta robots involves the design and implementation of controllers that can regulate the position, velocity, and acceleration of the robot’s moving parts, as well as ensure that the robot is stable and able to move smoothly and accurately. Control theory and algorithms are key aspects of delta robot control, including PID (Proportional-Integral-Derivative) controllers, state-space control, and model predictive control. The control of delta robots is important for ensuring that they can perform their intended tasks with precision and efficiency.

Together, the mechanics and control of delta robots play a crucial role in their design and operation. By understanding the mechanics and control of delta robots, engineers can design robots that are highly accurate, reliable, and efficient in a wide range of applications.

Chapter 3

Equipment and method of operation

Equipment

Stepping Motor.

SANMOTION Model No. PB PBM603FXE20

3 pieces

Figure 39 Stepping Motor SANMOTION Model No. PB PBM603FXE20

Link https://publish.sanyodenki.com/SANMOTION_PB_E/book/data/SANMOTION_PB_E.pdf

Stepping Motor SANMOTION Model No. PB PBM603FXE20 is DC Motor
(DC Motor) is a direct current electric machine that converts electrical energy into mechanical energy and then brings the rotation of the generated torque to use. An electric motor structure is like a generator but must supply DC voltage to the field windings for the motor to rotate and generate torque.

Motor Sanmotion (Sanyodenki) Model. PB603 FXE20
DC24V.
Maximum stall torque : 1.3 N.m
Rotor inertia : 0.4 x 10^–⁴kg.m²
Mass : 0.85 kg
Allowable thrust load : 14.7 N
Allowable radial load : 167 N
The maximum holding torque when stopping is 70 % of the maximum stall torque.
The maximum power consumption per Axis (Load Ration = 100%)
-Motor PBM603(3A.) Power Supply Capacity (24V. Input) : 72VA.
– Motor PBM603(3A.) Power Supply Capacity (36V. Input) : 120VA.
Encoder Spec
-Channel Number : 2 or 3
-Maximum Response Frequency : 300khz

SANMOTION-Model_No.PB-PBM423FXE20

1 pieces

Figure 40 Stepping Motor SANMOTION Model No. PB PBM423FXE20

Link https://publish.sanyodenki.com/SANMOTION_PB_E/book/data/SANMOTION_PB_E.pdf

Stepping Motor SANMOTION Model No. PB PBM423FXE20 is DC Motor
(DC Motor) is a direct current electric machine that converts electrical energy into mechanical energy and then brings the rotation of the generated torque to use. An electric motor structure is like a generator but must supply DC voltage to the field windings for the motor to rotate and generate torque.

Motor Sanmotion (Sanyodenki) Model. PB423 FXE20
DC24V.
Maximum stall torque : 0.39 N.m
Rotor inertia : 0.056 x 10^–⁴kg.m²
Mass : 0.35 kg
Allowable thrust load : 9.8 N
Allowable radial load : 49 N
Encoder Spec
-Channel Number : 3
-Maximum Response Frequency : 300kHz

TB6560 3A Stepper Motor Driver Board

4 pieces

Figure 41 TB6560 3A Stepper Motor Driver Board

A stepper motor driver board is an electronic circuit board that is used to control the motion of a stepper motor. It provides power and control signals to the motor, allowing it to rotate in a precise and controlled manner.

Stepper motor driver boards typically have several important components, including a microcontroller or other control circuitry, power transistors or other power electronics, and input/output interfaces for connecting to external devices or sensors. The driver board receives signals from the controlling device, such as a computer or microcontroller, and uses these signals to send current to the motor coils in a specific sequence.

Power supply 24V

Figure 42 Power supply 24V

A power supply rated at 24V is a device that converts incoming electrical power, typically from an AC source, into a stable and regulated DC output voltage of 24 volts. This DC output voltage can be used to power a wide range of electronic devices and systems that require a stable and reliable power source.

24V power supplies are commonly used in industrial automation, process control, robotics, and other applications where reliable and consistent power is critical.

The specific features and capabilities of a 24V power supply will depend on the application requirements, such as the required output current, voltage regulation accuracy, and input voltage range. It is important to select a power supply that is appropriate for the specific application and that meets the relevant safety and performance standards.

Sensor

Figure 43 IR Speed Sensor Module

IR Speed Sensor Module Specifications

Groove width is about 5mm
LM393 Comparator onboard to give digital output
Low power requirement
Senor output High when object is detected inn groove otherwise Low

4 Pins VCC, GND, digital pin out and analog pin out

Figure 44 Sensor pinout

Link https://quartzcomponents.com/products/4-pin-infrared-speed-sensor

To power this sensor connect either 3.3V or 5v supply to the VCC pin and connect GND pin to ground. Take the Digital Output from the DO pin and connect it to any GPIO pin development board or microcontroller. Read the output by use your program.

For this project, we use this sensor as a limit for the robot to determine. The maximum height that the robot arm can lift

Step-Down

Figure 45 LM2569

Link https://www.igetsolarcell.com/category/26/%E0%B8%A7%E0%B8%87%E0%B8%88%E0%B8%A3-%E0%B9%81%E0%B8%9B%E0%B8%A5%E0%B8%87%E0%B9%81%E0%B8%A3%E0%B8%87%E0%B8%94%E0%B8%B1%E0%B8%99%E0%B9%84%E0%B8%9F-step-up-step-down

Step-Down, also known as Buck Converter, is used to reduce the voltage from high pressure to a lower level. Using the switching-inductance principle (L), less heat and power loss exist. Unlike conventional 78xx / 317 series ICs using attenuation, the attenuation principle generates high heat. Buck converter circuit, when the voltage is lowered, the output current will increase.

Indicator light

Indicator lights, also known as signal lights or status indicators, are small lights on electronic devices or control panels that provide information about the device’s status or operation. They are typically color-coded and may blink, flash, or remain steadily lit to indicate different states or conditions.

Common examples of indicator lights include power indicators that show whether a device is turned on or off, battery indicators that show the level of charge remaining in a battery, and status indicators that show whether a device is actively processing data or waiting for user input.

Indicator lights are commonly used in a variety of settings, from consumer electronics like televisions and smartphones to industrial control panels and automotive dashboards. They are an important part of user interfaces, as they provide quick and easy-to-understand visual feedback about the status of a device or system.

Figure 46 Pilot Lamp

Link https://www.arduino4.com/product/901/%E0%B8%AB%E0%B8%A5%E0%B8%AD%E0%B8%94%E0%B9%84%E0%B8%9F%E0%B8%95%E0%B8%B9%E0%B9%89%E0%B8%84%E0%B8%AD%E0%B8%99%E0%B9%82%E0%B8%97%E0%B8%A3%E0%B8%A5-pilot-lamp-led-22mm-dc-24v

Indicator light (Pilot Lamp) can be considered as a common device. which almost every control cabinet or electrical cabinet must have this device to tell the status of various operations such as showing normal operation, downtime, alarm occurrence, overload occurrence, turning on-off the system, indicating the phase of the electrical system and others.

The voltage is available in various sizes, including 12VAC/DC, 24VAC/DC, 110 – 120VAC, and 220 – 240VAC, which the selection must first look at the size of the power in the control cabinet or the electric cabinet.

For this project, we use 3 pilot lamps of 24 volts with the red light showing the stop working status. The green light indicates that there is power. The yellow light indicates that this robot is working.

Emergency switch

Figure 47 emergency switch

An emergency stop switch is a safety mechanism used to shut off machinery in an emergency, when it cannot be shut down in the usual manner. The purpose of an emergency push button is to stop the machinery quickly when there is a risk of injury or the workflow requires stopping

Cable gland

Figure 48 cable gland

Cable glands are defined as ‘mechanical cable entry devices’ which are used in conjunction with cable and wiring for electrical, instrumentation & control, and automation systems, including lighting, power, data and telecoms.

Cable duct

Figure 49 Cable duct

Cable ducting is a cabling protection system in which electricity/power and other types of cables run through. Designed as durable and impact-resistant as possible to make sure cables are protected from the weather and any other external factor.

3.3V to 5V Control Signal Converter Module

AL-ZARD’s DST-1R4P-N is an optocoupler isolation board that comes in handy if you need to convert an electrical digital signal from one voltage level into another voltage level. A typical example is a digital 24V signal of an industrial sensor that has to be read by an ESP32 microcontroller

Carbon fiber pipe

Figure 50 carbon fiber pipe

For carbon fiber tube will be the robot’s arm, which has an outer diameter of 8 mm. inner circle 6 mm Length 300 mm.

Extension spring

Figure 51 Extension spring

Extension springs absorb and store energy as well as create a resistance to a pulling force. These springs are normally attached at both ends to other components and when these components move apart, the spring tries to bring them back together again.

Aluminum Profile

Figure 52 Aluminum Profile

Aluminum profiles are products born from aluminum alloys that are transformed into shaped objects through the extrusion process. Aluminum’s unique combination of physical characteristics mostly depends on this process. Aluminum extrusions are used in several fields because this metal is: Strong and stable.

Bearing

Deep groove ball bearing

Figure 53 deep groove ball bearing

Spherical bearing.

Deep groove ball bearings are the most widely used bearing type and are particularly versatile. They have low friction and are optimized for low noise and low vibration which enables high rotational speeds.

Figure 54 Spherical bearing

Connect the rod bearing to the joint bearing.

Rod joint bearing 6×6 mm

Relay

Relays are electrically operated switches that open and close the circuits by receiving electrical signals from outside sources.

In this case relays are used. For turning on and off the air pump to be used in conjunction with the vacuum.

Coupling

Figure 55 coupling

A coupling is a device used to connect two shafts together at their ends for the purpose of transmitting power. The main purpose of the coupling is to connect two rotating devices by allowing misalignment or end movement or both. in a broader context A coupling may be a mechanical device that connects the ends of adjacent parts or objects.

In here we use coupling size 6*8mm.

Universal joint

Figure 56 universal joint

The universal joint is used for the 4^th axis so that the 4^th axis can rotate in all directions.

In this case, we use universal joint size 6*6mm.

Programming

Use LabVIEW to program the robot controller.

Figure 57 LabVIEW

LabVIEW is a programming environment and development platform created by National Instruments (now NI) that is commonly used for visual programming and data acquisition. LabVIEW stands for “Laboratory Virtual Instrument Engineering Workbench.”

LabVIEW provides a graphical programming approach where users can create applications called “virtual instruments” (VIs) by connecting various functional blocks or nodes together using wires. These nodes represent different operations, such as mathematical calculations, data acquisition, signal processing, and user interface controls.

LabVIEW is often used in scientific and engineering applications, particularly in the field of test and measurement. It allows users to quickly build applications that interface with hardware devices, such as sensors, actuators, and instruments, and acquire, analyze, and present data in real-time.

The LabVIEW development environment includes tools for creating user interfaces, implementing control and analysis algorithms, and communicating with external devices. It supports a wide range of programming paradigms, including dataflow, event-driven, and object-oriented programming.

LabVIEW programs can be deployed on various platforms, including Windows, macOS, and Linux, and can target different hardware architectures. The software offers extensive libraries and toolkits for tasks like data analysis, control systems design, and signal processing.

Operation steps

Simulating by MATLAB program for design delta robot.

Pick and Place Robot Using Forward and Inverse Kinematics

This example models a delta robot performing a pick and place task. The robot picks up a part using a vacuum gripper, moves the part to each of the four markers on the table, drops the part at the first marker, and then returns to the home position. This example demonstrates how to:

Create Kinematics Solver objects and call them via MATLAB Function blocks to compute forward and inverse kinematics during simulation.
Model contact using Spatial Contact Force blocks.

Model

Figure 58 Simulates a pick-and-place Delta robot.

Link https://es.mathworks.com/help/sm/ug/pick-and-place-robot.html

Delta Robot Subsystem

The Delta Robot subsystem models a 3-DOF delta robot. The motion of the end effector is purely translational due to the kinematic structure of the robot. The robot’s actuators correspond to the three torque-actuated revolute joints mounted to the upper base plate. To mimic encoder data, the subsystem outputs the positions (angles) of the actuators. A camera frame is mounted underneath the base plate and looks down towards the end effector. The geometry associated with the end effector is exported via a Sim scape Bus to facilitate contact modeling. See the block mask for more information.

Open Delta Robot Subsystem

Figure 59 delta Robot Subsystem

Link https://es.mathworks.com/help/sm/ug/pick-and-place-robot.html

Planning and Control Subsystem: Forward and Inverse Kinematics

Because trajectory planning for the end effector is done with respect to the xyz coordinates of the robot’s camera frame, a forward kinematics map is needed to transform the positions and velocities of the actuators to the position and velocity of the end effector. Similarly, an inverse kinematics map is needed to transform the desired position of the end effector computed by the planner to the corresponding positions of the three actuators. These forward and inverse kinematics computations are done using Kinematics Solver objects. The objects are defined as persistent variables in the functions sm_pick_and_place_robot_fk and sm_pick_and_place_robot_ik. These functions are called by the MATLAB function blocks Planning and Control/Forward Kinematics and Planning and Control/Inverse Kinematics highlighted below. To speed up computation and help ensure the Kinematics Solver object for the inverse kinematics problem finds the desired solutions, the previous solution is used as the initial guess for the current problem. Whenever the parameters of the Delta Robot subsystem change, the sm_pick_and_place_robot_fk and sm_pick_and_place_robot_ik functions are cleared from memory so that the KinematicsSolver objects are regenerated at the beginning of the next simulation. This ensures that the KinematicsSolver objects and the model stay in sync.

Open Planning and Control Subsystem

Figure 60 Planning and Control Subsystem

Link https://es.mathworks.com/help/sm/ug/pick-and-place-robot.html

Planning and Control Subsystem: Path Planner

Planning occurs in the MATLAB Function block Planning and Control/Path Planner highlighted below. The planner transitions the robot between three different modes:

go to location directly above part
grasp part and move to goal location

go home

Whenever a mode begins, a trajectory is computed that takes the end effector from its current position to the mode’s goal position in a fixed amount of time. The trajectory is generated in two stages: first, a third-order polynomial is computed corresponding to the path of the end effector in xyz camera coordinates from its current position to the goal position; second, a fifth-order polynomial is computed which is used to scale the time along the path such that the initial and final velocities and accelerations are all zero. A mode transition occurs when the position and velocity of the end effector are sufficiently close to the goal values. Given the current time, the planner returns the desired position and velocity of the end effector along the trajectory as well as the desired state of the vacuum.

Open planning and control subsystem

Figure 61 planning and control subsystem

Link https://es.mathworks.com/help/sm/ug/pick-and-place-robot.html

Planning and Control Subsystem: Controller

The Planning and Control/Controller subsystem highlighted below contains a discrete time PID controller that drives the actual positions of the actuators to their desired values.

Open planning and control subsystem

Figure 62 planning and control subsystem

Link https://es.mathworks.com/help/sm/ug/pick-and-place-robot.html

Figure 63 Trial simulation working area

Delta Robot design

Robot dimensions

Figure 64 Dimensions of robot

Base radius (f) 256.26 mm Distance from center of machine base to center of each motor shaft.

Bicep length (rf) 200.0 mm Distance from motor shaft to elbow

Forearm length (re) 336.0 mm Distance from elbow to the wrist

End Effector radius (e) 63.0 mm Distance from wrists to tool

Base to floor distance (b) 400.0 mm Distance from floor to base

Figure 65 robot point

When we get the results of our simulation and we use that variable to design our delta robot

When designing a delta robot, we will design it as close as possible to this picture. This will complicate the Delta robot control equation and cause control

Base

Figure 66 Design base

The top base uses aluminum. of delta robots the old one of the senior’s about 419 mm in size and 10 mm thick.

The base for mounting the motor

Figure 67 base for mounting the motor

The base for mounting the motor 40x75mm

Planetary Gear 1:4

Figure 68 planetary gear 1:4

Figure 69 Exploded View of Gearbox

Link https://drive.google.com/file/d/10BaiU6B1mOPdtQ5bL4Jx-FowP_rL77YF/view?usp=sharing

Gearbox make from 3d printer

Figure 70 part of gear

Fix and assemble the gear 

From the past There was a problem with the gear. nut used for fastening go in too much tilt the gear 

Solved the problem by using a 3D printing machine to print the base of the new gear by adjusting the resolution of printing more from the original 40 percent to 60 percent. 

Figure 71 adjust the resolution of using a 3D printer, Print Gear.

Figure 72 start assembling the gear from the base. and the middle gear

  Figure 73 attach the bearing to the gear mounting bracket. 

   Figure 74 use a vise to compress the gear lock onto the bearing

  Figure 75 Attach the sprocket to the sprocket holder.

Figure 76 attach the sprocket and sprocket holder to gear outer ring

  Figure 77 put it all together 

We now have 1 gear, which has a gear ratio of 1: 4. 

Gearboxes are used to reduce the lifting force of the robot.
Size of bearing 20*27*4
3*10*4
45*58*7

Upper arm

Figure 78 Upper arm of the delta robot

Design the upper part of the robot arm with SolidWorks program to be 200 mm long and 6 mm thick.

Figure 79 Set for print upper arm

Use a 3d printer to print by setting the quality value to Dynamic and setting the infill density to 60 percent. In the Creality Slicer program.

Figure 80 Upper arm

Support senser and sensor

Design the installation of a sensor that will be used to determine the limit of rotation of the arm or set home position. 

Figure 81 design to support installation of sensor

Figure 82 sensor

Figure 83 Installing a device that will allow the sensor to detect

Figure 84 Equipment attached to the arm Used for mounting the sensor to allow detection.

Figure 85 The device that will provide the sensor to detect

Rod end

Figure 86 Rod end

Rod End is used in axis 1,2,3 to allow it to move in all directions.

Use a 3D printer to print the Rod bearing.

Figure 87 set for print rod bearing

Shaft

Figure 88 Shaft of the arm

Figure 89 drawing of shaft

The shaft is made of 8 mm aluminum, machined at the ends to 6 mm, and gouged 0.8 mm deep to 6 mm.

with teacher Sopin’s help in turning.

Lower arm

Figure 90 Model lower arm Figure 91 Lower arm

Design the lower part of the robot arm with the Solidworks program to be a length of 300mm, Diameter of 8mm. And used carbon fiber tubes.

End-effector

Figure 92 Design the bottom base

Figure 93 Set for the print bottom base

Use a 3d printer to print by setting the quality value to Dynamic and setting the infill density to 60 percent and generate support. In the Creality Slicer program.

Delta Robot 4^th arm above

Figure 94 4^th arm above

The 4^th arm is made of aluminum with a size of 32x180mm.

4^th arm below

Figure 95 4^th arm below

4^th arm below made of 3D printer with a size 12x12x150 mm.

Assemble delta robot

Figure 96 design delta robot

Figure 97 Exploded View 3 arm of Robot

Link https://drive.google.com/file/d/1NGNW0YS0I33XU4c1r2IMZAoT-9z_X7iW/view?usp=sharing

Figure 98 attaching arms 1, 2 and 3 to the base of the robot.

Link https://drive.google.com/file/d/1QQrp5XrFNNlFJkMsQMrMzYbrTJLlRtb9/view?usp=sharing

Figure 99 exploded view 4th arm of Robot

Link https://drive.google.com/file/d/1OFhnY0hQnwTlOyabIcV2nAxBKusD3_nO/view?usp=sharing

Figure 100 add a 4th arm to the robot.

Link https://drive.google.com/file/d/1iUsZfZ3Wzi4vKbxodMVSPvFmBoAbHbpl/view?usp=sharing

Vacuum gripper

Figure 101 Vacuum gripper

We use a vacuum gripper to pick and place items by using an air pump connected to a vacuum gripper.

Control cabinet design of deta robot

Figure 102 control cabinet installation

Figure 103 design installation of various equipment inside control cabinet

Inside the control cabinet is a NI myRIO board, stepdown, motor driver, power supply 24v, 3.3V to 5V Control Signal Converter Module, etc.

Control delta robot

Figure 104 flow chart of control delta robot

Manual control delta robot

joy stick

Figure 105 program joy stick

For the picture above shows the design of the LabVIEW program that will be used to connect the joystick.

Figure 106 program control robot by use joy stick

The figure above shows the design of a LabVIEW program that controls the robot using a joystick.

Is to bring the joystick program to connect to the program of the robot

Auto control delta robot

Figure 107 program control motor 1,2 and 3

The figure above shows the program design that will be used to run the three motors of the robot. which has been calculated inverse kinematics and can specify the position of movement in various points of the robot

Figure 108 program control motor 4

Figure 109 program to calculate x, y and z points

Figure 110 program to calculate x, y and z points

Figure 111 program to calculate x, y and z points

In Figures 109 to 111, it is calculated to allow the robot to move to the desired point.

Figure 112 A page for all programs used to control the robot.

In Figure 112 is the window used to control the entire robot.

How to use the Delta robot

Set up delta robot

Check port I/O of NI myRIO board

Figure 113 Check port encoder of the NI myRIO board

Test that the encoder is working.
In this image, we moved the motor up and down to see the encoder’s behavior.

Figure 114 Check port digital input and output

Check that the digital input and digital output ports can be used.

Set sensor of 3 arm

Figure 115 set sensor

Verify that the sensor is working.

Move the sensor parallel to the robot arm. to set the limits of the robot to prevent the robot from moving beyond the specified limits and can set a starting point from this point

Various functions in the operation of the robot

Home position.

Figure 116 home button

Click Set home. The robot will be back at position 0 or when sensor detect that we originally set up and click home again robot will switch to run GCODE mode

Set Target Position

Figure 117 Set the position of the robot movement.

According to Figure 117, the robot will be in the first place where we entered the data. Notice that the run GCODE box is a number 0, that is, the robot will run by going to the position entered in 0, which is x=0, y=0 and z=-220.
If you want the robot to move to the next position, enter the x, y and z positions at point1, point2, point3 respectively.
A maximum of 10 robot positions can be entered here.

Set speed.

Figure 118 set speed of robot

How to set speed of robot
To adjust the speed of the motor, PID gain and output range must be adjusted.
The PID gains channel is the PID value can be tuned.
Output range is to adjust the speed of the motor.

Chapter 4

experimental results

Test gearbox with stepper encoder

Test Gearbox 1:16

Gearbox Rotation Test

Figure 119 Gearbox Rotation Test

Link https://www.youtube.com/shorts/km2OfgVieew

Figure 120 Gearbox Rotation Test 2

Link https://www.youtube.com/shorts/YVuxZsBbOhQ

Test Accuracy Degree of the robot

Figure 121 Test load of motor 1kg

Link https://www.youtube.com/shorts/IJ_XYvrAD6M

Figure 122 Load of motor with gear 1:16

For the motor load test, has err values in varying degrees. according to the table above This may be caused by the calculation of degrees in the program. and tools used to measure degrees that cause the degree to be inaccurate.

Gearbox 1:4

Test Accuracy Degree of the robot

Figure 123 Load of motor with gear 1:4

In Figure 123 is a weight lifting test table. and movement to different degrees of each robot arm in conjunction with the gearbox 1 to 4

The lack of error in the table may be because we have omitted the decimal point.

Test the movement of delta robot

Motor test with gear and encoder After being assembled into the delta robotic arm.

Figure 124 Test control robot with gearbox

Link https://www.youtube.com/shorts/sTEQRinHgsg

Figure 124 shows the control of a 3-axis delta robot with gear box.

Figure 125 Test position of the robot

Link https://www.youtube.com/watch?v=q0T7FBQkZjs&t=4s

Fig. 125 tests the accuracy of movement at different points along the x, y, and z axes of the robot, with the robot moving to the tip of the drill bit.

Figure 126 Test speed of the robot

Link https://www.youtube.com/watch?v=zLvM19l2KzQ&t=51s

Figure 126 is the speed test of the robot.

Test manual by joystick

Figure 127 Connection between LabVIEW program and joystick xbox

Link https://www.youtube.com/shorts/I8XNKdtWneU

Figure 127 shows the connection between Xbox joystick and LabVIEW program.

Figure 128 Control delta robot by use joystick

Link https://www.youtube.com/watch?v=cboZI5UcZvM

Figure 128 is controlling the movement of the robot to various points along the x, y and z axes by controlling it through a joystick.

Test movement by Inverse & Forword kinematics

Figure 129 The robot lifts things and moves around.

Link https://www.youtube.com/watch?v=HCK4g7uBukw

For Figure 129, the load is lifted and moved in different combinations within the robot workspace. But there will be a slight vibration problem when the robot is moving.

Figure 130 Test the vibration of the robot during movement.

Figure 130 shows the vibration of the robot while it is moving.

Chapter 5

Summary of experimental results

Summary

Robot base design or designing the arm assembly to be in a plane that enters the center will help the robot to move more accurately.

In the version with a 1:4 gear box, it can support the weight of about 0.8 kg per arm.

In current version There will be a vibration of the robot. which may be caused by Poor mounting of the base or poor tuning of the PID used for robot movement. Or it may be caused by changing from a 1:16 gear box to a 1:4, which has more speed.

Suggestion

If you want the robot to be able to lift heavier things Might have to adjust the ratio of the gear box more. For example, change from 1:4 to 1:16 and so on. But must be designed Have the arm cut into the center of the robot’s base. for accurate movement and easy calculation

To solve the problem of robot vibration, it may be necessary to adjust the PID value or adjust the installation of the robot to make it more stable and strong.

Wire re-arranging, as current versions of wires have overlapping wires that can cause wires to overheat. may cause a fire

Appendix A

Adjust the arm to center.

Figure 131 Adjust the arm to center.

Adjust the arm to take it into the center. so that the robot moves to different points precisely

Gripper

Figure 132 Test gripper

Link https://www.youtube.com/shorts/fINLojBqiOE

Arduino with motor

Test the encoder with motor. 

Figure 133 test encoder by use Arduino

Link https://www.youtube.com/watch?v=jloALvQNsIo

Test the communication between the LabVIEW program and the Arduino program  

Figure 134 communication between labview and arduino

Link https://www.youtube.com/watch?v=VKNIJOxWhWo

Figure 135 communication between labview and esp32 send value to Influxdb

Link https://drive.google.com/file/d/1LqI2rjlK-PkW2Bs3k_OgCq15iVI2qLS4/view?usp=sharing

Figure 136 Python GUI + Esp8266 control motor

Link https://www.youtube.com/watch?v=hH9P9Y1jvMg

Figure 137 create webserver by use Esp8266 control motor

link https://www.youtube.com/watch?v=HdKb1-dqJxk

Test the vibration of the robot.

Figure 138 Test the vibration of the robot.

Figure 139 Test the vibration of the robot.

Figure 140 Test the vibration of the robot.

Figure 141 Test the vibration of the robot.

Figure 142 Test the vibration of the robot.

Figure 143 Test the vibration of the robot.

Figure 144 Test the vibration of the robot.

Figure 145 Test the vibration of the robot.

Figure 146 Test the vibration of the robot.

Figure 147 Test the vibration of the robot.

Figure 148 Test the vibration of the robot.

Figure 149 Test the vibration of the robot.

Figure 150 Test the vibration of the robot.

Figure 151 Test the vibration of the robot.

Figure 152 Test the vibration of the robot.

Figure 153 Test the vibration of the robot.

Figure 154 Test the vibration of the robot.

Figure 155 Test the vibration of the robot.

Figure 156 Test the vibration of the robot.

Figure 157 Test the vibration of the robot.

Figure 158 Test the vibration of the robot.

Figure 159 Test the vibration of the robot.

Figure 160 Test the vibration of the robot.

Figure 161 Test the vibration of the robot.

Test work of robot

Figure 162 use robot draw

Bibliography

https://www.youtube.com/watch?v=hH9P9Y1jvMg
https://www.youtube.com/watch?v=HdKb1-dqJxk

Gulf Thai

Delta Robot Design and Development