top of page

A Complete Guide to Robotic Arms

complete guide to robotic arms

In this guide, we’ll look at exactly what are robotic arms, what are its application, and how can 3d printing help in building a DIY robotic arm

What is a Robotic Arm?

Robotic arms are highly efficient machines designed to carry out specific tasks with speed and precision motors commonly power them and find extensive use in industries requiring consistent performance of repetitive tasks, such as manufacturing and assembly. These arms mimic the structure and movement of a human arm through joints and manipulators. They can function as standalone machines or be part of larger equipment setups. In various industries, you'll find them either mounted on benches or the floor, typically made of strong steel or cast iron. Whether big or small, robotic arms are electronically controlled for accuracy and reliability. They usually have 4-6 joints, resembling the key parts of a human arm, like the shoulder, elbow, forearm, and wrist.

Industrial robot arms are incredibly fast and powerful machines. However, it's crucial to prioritize safety when programming and using them. When used correctly, these robot arms can significantly boost production rates and improve the accuracy of tasks like placing and picking items. They can also handle heavy lifting and moving tasks that would be challenging for humans to do quickly.

What is a Robotic Arm?

What are the applications of Robotic Arms

Robotics has a wide range of applications across different industries and sectors. Some of the most common applications of robotics include:


In factories, robotic arms are like the superheroes of manufacturing. They're incredibly handy at jobs like putting things together, welding, and painting stuff. These arms make sure everything is put in just the right spot and held together tightly, which means the things they make are top-notch quality every time. Plus, they're really good at lifting and moving heavy or dangerous stuff that could be risky for people to handle, making the whole factory a safer place to work.


Robotic arms are super handy in a bunch of important stuff like medical tests, giving out medicine, and even doing surgeries. They're like super-precise tools for doctors. When doctors use them for surgeries where they only make tiny cuts, it helps patients get better faster and with less pain.

In labs, these robotic arms speed up the process of doing experiments. They make it easier for scientists to get consistent results, which is a big deal because it means they can trust their findings more. All this tech wizardry is making big waves in medicine and science, leading to cool discoveries that make people healthier and happier.

Food Industry

Robotic arms are becoming popular in the food industry. They're great for handling food because they're super clean and accurate. These robots can gently pick up things like cakes, candies, and fruits, making sure they stay perfect until they're ready to eat.

Logistics And Warehousing

Robotic arms are like super-powered helpers in warehouses. They do all sorts of heavy lifting, like moving big stuff from conveyor belts, handling delicate items gently so they don't break, and stacking pallets perfectly every time. This means less work for people, more stuff getting done, and fewer accidents on the job.

Electronics Manufacturing

In electronics factories, special machines with robotic arms carefully check tiny flaws on printed circuit boards (PCBs). These flaws are so small that people can't see them. This careful checking ensures that electronic devices work well and don't have any problems.

Space Exploration

Robotic arms inspect critical components like turbine blades and composite materials, ensuring aviation safety by promptly identifying and addressing imperfections.


Robotic arms are now being used at construction sites to do hard work. They can lay bricks, pour concrete, and do other tough jobs. These robot workers make building things easier and faster.

Those are just a couple of examples showing how robotic arms are being used in many different industries.

Overall, robotic arms can do all sorts of tasks and will keep being an important technology that changes how we live and work. Advancements in robot tech have already created new chances for efficiency and cost savings and will keep doing.

This original STL files are now uploaded as well.

download the file(s) and print them on your 3D printer

How can 3D Printing Help in Building a DIY Robotic Arm

Step 1: Print the Parts

Print the Parts in robotic arms

The arm is quite long, around 20 inches, which means printing it takes a good amount of time and material. we will adjust the parts to fit on the 3D printer bed, and some can be printed together to save time. we used a 0.25mm resolution and hollow fill for all parts, with other settings at default. Using a raft helped the parts stick to the print platform, especially since my table wasn't perfectly level.

Most parts have flat sides that should touch the platform during printing. They also have delicate tabs for cable holding, so be careful when removing raft and support material. Reviewing the STL file beforehand helps identify delicate areas.

Step 2: Arduino Code

robotic arms in Arduino Code

While you're waiting for the 3D-printed parts, you can start working on two things: uploading the code to the Arduino and soldering the electronics. The code for controlling the servos with Arduino is quite simple. Some buttons control the joints and gripper servos. Pressing these buttons increases or decreases the position of the servos by one step. Additionally, there's a potentiometer connected to the base, which controls its rotation. Depending on how you wire the buttons, you might need to adjust the PINs in the code. Before assembling the arm, it's a good idea to test the code with your servos. This ensures that their movement limits match what's defined in the code. Testing them after assembly could potentially damage or even break the arm. If you're interested in making your arm perform simple automated tasks, you can use the same physical setup with different code. However, it's important to note that since there's no positioning feedback, the arm's accuracy is limited by the precision of the servos.

Step 3: Extend the Servo Cables

Extend the Servo Cables in robotic arms

To make sure the cables reach the right spots on the arm, we'll need to lengthen them. Here's what you do: Cut the cable, then add an extension by soldering it between the servo and the connector.

Here's how much you need to extend for each servo:

  • For the servo at the base, you don't need to extend it.

  • For the two servos at the lower joint, extend each cable by 5 inches.

  • For the servo at the middle joint, extend it by 10 inches.

  • For the servo at the upper joint, extend it by 15 inches. This one's a micro servo.

  • Lastly, for the gripper servo, extend it by 18 inches. Also, a micro servo.

Step 4: Build a Circuit Board

Build a Circuit Board in robotic arms

The arm's circuit board mainly helps organize the wires and signals better, rather than adding more parts. First, put in the resistors, then connect the different plugs (remember, some are male and some are female). Lastly, solder the connections in place

Step 5: Build the Gripper

Robotic arms Build the Gripper

Once you have all the pieces, you can start putting them together. First, push the micro servo with the longest cable into the gripper base and run the cable through the channel. Attach the 4-pronged horn to the micro servo and rotate it to the position where you want the gripper to be most "open". Push on the claws, making sure the gears fit together properly. Push the other micro servo into the side of the gripper and assemble the rest. The top of the gripper has pins that help hold the claws in place, and you may need to lightly sand them a bit so they fit easily (but don't force them or they could break).

Step 6: Route the Cables

Robotic arms Route the Cables

Now start working on the still-open side of the middle segment. Gently push the cables into their channels and under the tabs. To make sure there's enough slack for the joints to move, rotate the part so the cable is as far from the channel as possible and then loosely clip the cable in. Keep routing the cables, carefully removing (and then putting back) any braces if needed to reach the clips. If you use a tool to help clip in the cables, be careful not to pinch or accidentally cut the wires.

Step 7: Attach the Arm to the Base

Attach the robotic Arms to the Base

Connect one standard servo to a servo mount and place both mounts in the rotating base. Put the top two bolts for the second servo in its mount, but don't attach the servo yet. Rotate the mounted servo until it's at its maximum turn and gently slide in the arm, pressing it onto the servo horn. Push the second servo (after rotating it to its maximum turn first) into the other horn and secure it with the remaining bolts. Thread the servo cables through the holes in the rotating base.

Step 8: Make the Control Panel

Robotic arms Make the Control Panel

The control panel has 8 buttons, a potentiometer, an LED, and an on/off switch. To make things easier, it's best to connect wires to all the parts before fixing them in the base. The buttons and potentiometer I used had threads, so I could screw them onto the base.

The LED and on/off switch fit snugly into the base. Run a wire from one terminal of the switch out through the side hole and wrap a black wire around it (this wire provides the ground for the circuit). Once all the parts are in place, attach the knob to the potentiometer

Step 9: Add the Circuit

Add the Circuit in robotic arms

Now, connect the cables from the control panel to the circuit. Plug the header cable into the row of female connectors located just below the resistors. Another cable, which is situated below that, should be connected to the Arduino. The 5V cables from the potentiometer and buttons should be attached to the 5V headers. Connect the ground cables from the potentiometer, LED, and black wire to the GND headers.

Step 10: Plug in the Arduino and Servos

Plug in the Arduino and Servos in robotic arms

Connect the Arduino board to the cables you created earlier. Then, attach the servo plugs to the male headers located at the top of the circuit board.

Step 11: Close Up the Base and Play

Close Up the robotic arms Base and Play

Make the electronics flat and fit the control panel onto its matching bottom piece. Then, close the two parts together. Get your power supply, and you're good to go.


bottom of page