i. Head Assembly
Insert the ultrasonic module into No. 1 board and secure it with M1.4*8 screws and M1.4 nuts.
Use a M3*5 screw to secure the M3*8 two-way hexagonal copper post on No. 1 board.
ii. Electrical Module Assembly
Use a M3*5mm screw to mount the previously installed circuit board on No. 1 board.
Use M3*5 screws to fix M3*25 Bi-pass Copper Standoff under the No. 1 board.
iii. Servo Assembly
Use M2*8 screws and M2 nuts to mount the servo on the corresponding position on the No. 2 board. (Note the direction of the servo installation)
Secure the No. 1 and No. 2 boards with M3*5 screws. Note that the side of the servo shaft should be mounted on the side of the USB port.
Use two M1.5*5 self-tapping screws to fix the 2-arm rocker arm to the No. 4 board and use the same method to install another No. 4 board.
Secure one of the round holes on the 4th and 5th boards with M3*8 Countersunk screws and M3 self-locking nuts.
Use the same method to secure the other round hole on the 4th and 5th boards, as shown in the following figure:
Use two M1.5*5 self-tapping screws to secure the 1-arm rocker arm on the No.4 board.
Install another No.4 board in the same way.
Turn the No. 6 board with the countersunk side down and secure the No. 6 board to the ① module (right leg) described above with the M3*8 countersunk screw and the M3 selflocking nut.
The same method can be used to secure the No.7 and the ② module (left leg).
iv. Servo INSTALL Test
Connect the upper-right servo to port 9, the yellow cable to the signal pin, red to the positive pole and brown to the negative pole. Then connect the lower-right servo, the upper-left one and the lower-left servo to pin 10, 11 and 12 respectively in the same way.
Connect the Nano board and the computer with a USB cable. Open the program simple_robot.ino, and upload the program to the board. Now, it’s in install process.
Then power on the robot, keep the power on and the servo connect to the board.
v. Foot Assembly
Assemble the No.4 board on the left leg and the No.3 board on the cover together with the upper-left servo through the servo’s matching screws (the smallest screws in the packaged with servo). Try to keep the edges of the 4th board and the servo parallel to each other. They need to be reinstalled if not parallel to each other.
Put a servo shaft on No.3 board, and then secure the lower-left servo (pin 12) to the No.5 board with M2*8 screws and M2 nuts. Note that the servo shaft should be close to the inside of No. 7 board.
The lower-right servo (pin 10) is installed in the same way.
Insert the 1-arm rocker arm into the two servos and secure them with the matching screws of the servo.
The effect chart is as follows:
vi. Battery Assembly
Attach one side of velcro tape to the bottom of the No. 1 board and the other side to the battery.
Insert the battery into the battery cable and plug the other end into the expansion board.
Lastly, paste the battery on the No. 1 board
vii. Servo CALIBRATION Test
Open the program and go to Line 39, disable the INSTALL and activate the CALIBRATION. Select the correct board and port, then upload the sketch. If the robot is not set right, change the angle and upload the code until it is.
Tips for calibration:
① If the right leg is toe out, you need to decrease the upper-right servo’s angle; if it is toe in, you need to increase the angle.
② The calibration method for the left leg works the opposite way for right leg.
③ If the right foot’s sole faces outward, you need to decrease the lower-right servo’s angle; if its sole faces inward, you need to increase the angle.
④ The calibration method for the left foot works the opposite way for right foot.
Here we take this robot as an example. After uploading the code, press thepower button on the servo control board, pick up the robot and you will see the slight change of the robot legs and feet:
Observe the robot above we can know: ① right leg is toe out, ② left leg is toe out, ③ right foot’s sole faces outward, ④ left foot’s sole faves outward.
Then go back to Line 15.
Thus we can calibrate as follows:
① Decrease the upper-right servo’s angle
Change 95 degrees to 90 (array_cal[0]: is the upper-right servo’s rotation angle);
② Increase the upper-left servo’s angle
Change 115 degrees to 120 (array_cal[2]: is the upper-left servo’s rotation angle);
③ Decrease the lower-right servo’s angle
Change 100 degrees to 90 (array_cal[1]: is the lower-right servo’s rotation angle);
④ Increase the lower-left servo’s angle
Change 95 degrees to 100 (array_cal[3]: is the lower-left servo’s rotation angle);
i.e.: In line 15, change code to array_cal[4] = {90, 90, 120, 100}; Then click Upload.
The edge of upper-left plate and upper plate are parallel with each other, but upper-right is not parallel to the upper one, the deviation angles of lower-left and lower-right servos are decreased.
Change code in line 15 to array_cal[4] = {80, 80, 120, 110}; Then click Upload.
Observe the four servos to make sure they are in proper angle, then the servo calibration is completed. You can do fine tuning with value changing of “1” each time, if there is a little deviation.
Since the servo angles on legs and feet differ, the final calibrated angles (array_cal[4]) will be different too. It will take multiple times of calibration, you should adjust in patience.
viii. Ultrasonic Connecting
Plug one end of the ultrasonic connecting cable into the ultrasonic module, and the other to the servo control board.
Connect pin TRIG of the ultrasonic to pin 4 of the board, ECHO to pin 3, VCC to VCC and GND to GND.
ix. Servo RUN Test
Go to Line 39 again, disable the CALIBRATION line. Activate the operating programe “run” and burn the program to the board.
After burning successfully, unplug the USB cable and press the power button on the servo control board.
You will see the robot moving forward. When encountering an obstacle, it will make a turn and then go forward again.
x. Wire Arrangement
Twine the servo wire and 4-Pin anti-reverse cable on the No. 1 board.
So far the robot has been assembled successfully, it’s easy if you follow our steps closely.
Hope you enjoy the fun of the bot, thanks for watching.