How to Build an 8-servo Spider-like Robot (a Quadruped) Using ACEBOTT

Build Your Own Spider Robot with the ACEBOTT Kit — A Perfect STEM Project for Beginners!

Have you ever dreamed of building a robot that can walk like a spider—but thought it was too complicated? Whether you're a parent, educator, maker, engineer, or a curious young learner, this hands-on project is the perfect way to dive into the world of robotics and coding.

In this guide, we’ll walk you step-by-step through building and programming the ACEBOTT Bionic SpiderBot, an agile, four-legged robot designed to introduce the basics of mechanics, electronics, and coding. Using 8 servo motors as its “muscles” and an ESP8266 board as its “brain,” this STEM robot kit provides a fun and rewarding learning experience for all ages.

As you build this robot spider, you'll gain hands-on experience in:

1. Mechanical assembly and servo control
2. Arduino programming using simple code
3. Circuit building
4. Logical thinking and creative problem-solving

This project uses the beginner-friendly components from ACEBOTT's STEM robot kits, making it accessible for anyone eager to learn—no prior experience required! It’s also a fantastic addition to any classroom, makerspace, or at-home learning environment.

By the end of this tutorial, you’ll not only have your very own working spider robot, but also a strong foundation in robotics that can lead to more advanced projects.

Ready to bring your robot to life? Let’s begin this STEM-powered journey with ACEBOTT’s STEM toys and make learning truly come alive!

ESP8266 V1.0 - 1 PC

Spider-Shield-V1.0 - 1 PC

Servo MG90 9G - 8 PCS

USB Cable 1M - 1 PC

Screwdriver - 1 PC

Acrylic Board - 1 Pack

Nylon Cable Ties - 3 PCS

M3*10MM Round Head Screws - 20 PCS

M3*25MM Dual-pass Copper Pillar - 5 PCS

M3 Nickel-Plated Nuts - 10 PCS

M2 Nickel-Plated Nuts - 20 PCS

M2.5*4MM Round Head Screws - 2 PCS

M2*14MM Round Head Screws - 20 PCS

This is the main construction step where we will build the entire quadruped robot. Follow the sub-steps carefully. For visual reference, please refer to the assembly manual images attached above.

Part 1: Main Body Assembly

1. Preparation: Start by peeling off the protective paper from all the acrylic pieces.
2. Attach Expansion Board: Secure the Servo Expansion Board to the main Body Acrylic piece using the four M3*25mm copper pillars and four M3*10mm screws.
3. Install Body Servos: Mount the first four servos onto the main body. Crucial: Ensure the servo axis is positioned closer to the outer, long edge of the body, as shown in the diagrams.
4. Install Controller Board: Place the ESP8266 Controller Board on top of the expansion board. Make sure the USB port on the ESP8266 aligns with the toggle switch on the expansion board.

Part 2: Leg Assembly

1. Assemble the Leg Joints (Coxa & Femur): Attach the single-axis servo horns to the Coxa structures. Then, connect the Coxa and Femur parts to create the main leg joints. You will make four of these – pay close attention to the orientation for the left and right sides (2 for each side).
2. Assemble the Calves (Tibia): Install the remaining four servos into the Tibia structures (calves). Again, assemble two for the left side and two for the right, following the diagram's orientation.

Part 3: Final Assembly & Wiring

1. Attach Legs to Body: Mount the four completed leg assemblies onto the body servos. Important: Before fixing them, pass the servo wires through the designated holes. Do not fully tighten all screws immediately if the manual indicates to wait.
2. Connect Wires: Now, it's time for wiring.
3. Connect the four body servo wires to pins D1, D2, D6, and D7.
4. Connect the four leg servo wires to pins D0, D4, D5, and D8.
5. Wiring Rule: For all servos, the brown wire is GND, red is VCC, and orange is Signal. The brown wire should always be connected to the outermost pin.
6. Install Top Cover: Once all wires are connected, use the provided cable ties to neatly manage the wires. Then, secure the Body-Top cover with four M3*10mm screws.

Final Checks and Warnings

1. Battery: Your assembly is now complete! Before turning the robot on, insert a fully charged 18650 battery into the battery holder. Double-check that the positive (+) and negative (-) poles are correctly oriented.
2. CRITICAL WARNING: To prevent permanent damage to the servos, NEVER manually turn the servo shafts or force the legs to move when the robot is powered on.
3. Note: The servo kits may come with extra accessories like control discs. These are not needed for this project and can be set aside.

1. Open Arduino IDE

Make sure you are using Arduino IDE version 2.x or later.

2. Open Preferences

1. Go to the File menu (on macOS, go to Arduino menu).
2. Click on Preferences.

3. Add Board Manager URLs

1. In the Preferences window, find the field labeled Additional Board Manager URLs.
2. Click the icon next to this field (clipboard with a chain symbol).
3. In the popup window, enter the following URLs (each on a new line):

1. Click OK to close the popup, then click OK again to save the preferences.

4. Open the Boards Manager

1. Go to the Tools menu.
2. Select Board > Boards Manager.

5. Install the ESP8266 Package

1. In the Boards Manager window, search for esp8266.
2. Locate esp8266 by ESP8266 Community.
3. Click the version dropdown (e.g., 2.4.2), then click Install.
4. Wait for the installation to complete. You will see a confirmation message once it is successfully installed.
5. 
   

How to Install CP210x USB to UART Driver (for ESP8266 boards using CP2102)

If your ESP8266 board uses the CP2102 USB-to-Serial chip, you need to install the CP210x driver so your computer can recognize the board.

Windows

1. Download the driver from Silicon Labs official website:
2. https://www.silabs.com/developers/usb-to-uart-bridge-vcp-drivers
3. Scroll down and choose the correct version for your operating system (e.g., Windows 10, 64-bit).
4. Run the installer and follow the instructions.
5. After installation, reconnect the board. You should now see a new COM port in Arduino IDE under Tools > Port.

macOS

1. Go to the same page:
2. https://www.silabs.com/developers/usb-to-uart-bridge-vcp-drivers
3. Download the macOS version.
4. Open the .dmg file and follow the installation steps.
5. You might need to allow the driver from System Preferences > Security & Privacy after installation.

To properly align the robot legs and ensure smooth walking behavior, we need to calibrate the servo motors first. This step ensures that each leg starts from the correct mechanical position before the robot is fully assembled and programmed for movement.

What You’ll Do in This Step:

1. Upload the servo standby code (provided in the attached file)
2. Let the servos move to their standby positions automatically
3. Physically adjust the servo horns (arms) to match the desired pose
4. Secure the horns with screws once aligned

Why Calibration Matters

Servo motors must be aligned correctly so that all limbs move in harmony. If even one servo is misaligned, the robot may walk incorrectly or even damage itself. That’s why it’s critical to start with a known reference position — in this case, a custom standby pose where each servo turns to a pre-set angle.

Instructions

1. Upload the Standby Code
2. Use your Arduino IDE or compatible software to upload the 4.1standby.ino file provided in this project.
3. Wait for the Servos to Move
4. Once uploaded and powered, the servos will move to their predefined angles. This is your standby reference pose.
5. Do Not Force the Servos
6. Never rotate the servo shafts by hand — doing so can damage the gears inside. Instead:
7. Gently remove the servo horns (if already attached).
8. Reattach the horn so it aligns with the current servo angle.
9. Adjust the horn until the legs resemble the calibration pose shown in the reference image.
10. Tighten the Screws
11. After confirming the leg positions match the correct standby pose:
12. Insert the small screw into the center of each horn to secure it to the servo shaft.
13. Be careful not to overtighten.

Reference

Refer to the attached image to match the correct alignment of the robot legs during this calibration step. Make sure the stance is symmetrical and the body is level.

⚠️ Notes & Tips

1. Only perform this calibration before full assembly.
2. Always test your servo directions using the calibration code before writing movement logic.
3. After calibration, the robot will be ready for walking animations or custom gaits.

Now that the servos have been calibrated, your Sorbot (spider robot) is ready for action!

In this step, you can upload the motion control program that allows the robot to perform various movements such as:

1. 🔙 Move Back
2. ↪️ Rotate Left
3. ↩️ Rotate Right
4. 🆙 Push Up
5. 🤖 Standby
6. And many more!

You simply need to upload the program file that we’ve already provided

Steps to Upload the Motion Program:

1. Open the Arduino IDE
2. Make sure your Arduino IDE is installed and working correctly.
3. Connect your board via USB
4. Plug in your microcontroller to your computer using a USB cable.
5. Open the motion code file
6. Navigate to the .ino file provided (e.g., 4.2forward.ino) and open it in the Arduino IDE.
7. Select the correct board and port
8. Go to Tools > Board and select your microcontroller type.
9. Then go to Tools > Port and select the correct COM port (e.g., COM5 or similar).
10. Click Upload (Arrow button)
11. Upload the program to your board. Wait until you see the message: "Done uploading."
12. Observe the robot
13. Once uploaded, the robot will initialize and you may see default leg positions or standby pose.