Picar-X Lesson 2: Assemble 02

Basic Teaching Information

Suitable School Age

8-10 years old


90 minutes


Teaching Objectives

1.Guide students review the function of sensor module, what PiCar can do and how to play.

2.Through practical operation, students master the usage of installation tools (socket wrench, self-locking nut).

3.In this lesson, PiCar is to be completely assembled.

4.By referring to a real-world vehicle, make students understand how the steering wheel controls the driving direction of the car.

Important and Difficult Points of Teaching

Teaching Key Points

Guide the students to complete the assembly smoothly.

Teaching Difficult Points

Note: Do not fix the self-locking nut with socket wrench too tightly. Keep the corresponding parts flexible after assembly.

The structures of the connecting rod and front wheel are not easy to understood.

It is difficult for students to understand the zeroing of the servo. In this part, it is necessary to track and confirm the progress of each student.

Teaching Form

PPT presentation, cooperative group learning.

Teaching Media

Teaching Grouping and Teaching Aid

Teaching Group

Work in groups of one person.

Teaching Aid

PiCar part kits, pen, and programming growth manual.

Teaching Procedure

Teaching Stage

Teaching Content


1. Servo


Explain the importance and method of zeroing of the servo. Servo Zeroing: Set the initial value of the internal angle of each servo to 0°. Zeroing is very necessary to the later rotating adjustment of the servo arm.

Zeroing is executed according to the method in PPT. Students need to install each servo arm after the zeroing of servo.

5 minutes

2、Continue to Assemble

1. Let the students follow the PPT to complete the assembly.

2. On average, each step is limited to about five minutes.

3. The use method should be reminded when students use socket wrench to fix the self-locking nut. (Step 20 21 22)

Ensure that the screw is firm but not affect the flexible rotation of parts.

4. In the step 21, the suspended screw hole on the wheel faces forward for holding the connecting rod in the latter step.

5. In step 22, place the connecting rod on the central servo before screwing the nut. Then turn the front wheel left and right to see if it is flexible enough.

The structure is the equivalent of a car's steering system, whose devices pull the transmission rods to steer the two wheels.

6. When connecting the sensor module, students refer to the convention of wiring. Red represents the anode and black represents the cathode (ground).

“Next, we need to connect the sensor and the main control board through a cable. The white end of the cable has an anti-reverse structure, which cannot be inserted in reverse”

“Note the red cable and the black cable correspond to the VCC and GND marked on the module, which represent the anode and cathode. Connect the red cable to the red pin slot on the Robot HAT and the black cable to the black pin slot. The other cables are all data transmission cables. They should be connected as shown.”

7. After wiring and assembly, if there is enough time, the teacher demonstrates the use of cable wrap. That will be a little bit difficult to use, so students should be patient.

50-60 minutes

3. Summary and Reflection


1. What sensor modules are available on PiCar and what can they be used for?

2. What tools did you use? Do you have these tools in your home? Have you use them to assemble something?

3. Can you describe how the steering wheel controls the steering of the car?


What did we ask PiCar to accomplish today? What difficulties did we encounter and what did we learn from this process?

10 minutes

4、Material Arrangement


1. Ask students to put unused materials back in the box to avoid losing.

2. Next time, we'll formally learn how to program Parker to get the job done. Students can learn in advance about what programming is!

10-15 minutes