This instructable was created in fulfillment of the project requirement of the Make course at the University of South Florida (www.makecourse.com)
Often times we work with office computer remotely logged in from home. The problems come in when the computer is frozen sometime and it needs a fresh start (restarting the computer). In which case you have to step into the office and restart it yourself( mechanical action hard to do electronically without modifying the computer's power circuitry). This project TirggerX is inspired by this event. Since a long time, I was thinking about making a wifi enabled IOT device that can do a physical action like turn a switch or restart a computer remotely. So far this feature is somewhat missing with all the smart devices available in the market. So I decided to make my own. Now let's talk about what you need in order to make your own-
1. NodeMCu Amazon
2. SG90 Servo Amazon
3. Stepper with a linear slider Amazon.
4. 2 Stepper motor driver Amazon
5. Micro USB cable Amazon
Goals of the project-
Make a physical switch with sliding action in X and Y direction and tapping action in Z direction.
Step 1: 3 Axes Movement
For the linear (sliding x and y position) operation of the switch (Trigger), we need two axis motion which will be carried out by two stepper motor. The main trigger event which in the z-direction will be driven by a servo.
Step 2: 3D Design
Step 3: Base and Cover Design
First, the cover and base for the stepper motor were designed.
Step 4: 3D Design: Base Cover With Stepper
The stepper motor was designed for simulation. The above pictures show the base cover with the stepper motor installed
Step 5: 3D Design: Servo Assembly- Base for Servo
To attach the stepper motors linear slide with servo motor a mounting base was designed and attached.
Step 6: 3D Design: Circuits
1. Node MCU
2. Motor Driver
Both were included in the simulation and design.\
Credit: GrabCad .
Step 7: 3D Design: Cover Plate
The cover plate for applying adhesive to attach to the computer (as well as for aesthetic reason) was designed and attached to the full assembly.
Step 8: 3D Design: Full Mechanical Assembly
Step 9: Control Circuit: Block Diagram
The TriggerX device is controlled by an Android APP interface which was made by Blynk.
The app will communicate with the node MCU (through the internet) installed in the device and control the servo as well as two stepper motor through two stepper driver module TB6612.
Step 10: Circuit Schematic
The Circuit Schematic is as shown in the picture. The NodeMcu is connected to the stepper motor through the stepper motor driver and directly to the servo motor.
Step 11: Configuring the Blynk APP
The Blynk App Can be downloaded from the link given here.
Two sliders and One button were included according to the configuration showed in the picture.
From 0 to 300 is the number of stepper steps and 120 to 70 is the servo angle control signal.
Step 12: The Code
First, the new project was created in the app and authorization code was used in the Arduino IDE code.
The Code is explained in the file.
Step 13: 3D Printed Assembly With Circuits
Step 14: Mounting on a Computer.
The device was mounted on a computer using double-sided adhesive tape.