laserPointer

This project will be about driving 2 servos and 1 laser using a esp32 and a power supply to to point to parts or tools, I own around my garage. This project will be connected to another project called GParts which is also located on this github space.

Wiring

How to connect a 6V laser to esp32 and and be able to control it's brightness

• BC337 Base (middle pin) to ESP32 D4
• BC337 Collector to GND
• BC337 Emitter to Laser GND
• Laser VCC wire to 6V

Parts used in the project

• Laser 650nm 5mW Red Cross
• Two pieces Servo motor RDS3225
• ESP32 Development Board
• Power supply 6V - 6A
• HLK-PM01 5V
• BC337 -25 Transistor

Wiring diagram

GND                                      +6V
 ├──────────────────────┐                 │
 |        ╔═══════════╗ |                 │
 |        ║  -BC337-  ║ |    ╔═════════╗  |
 |        ║           ║ |    ║ -Laser- ║  │
 |        ║ Collector ╟─┘    ║         ║  │
 |  ┌─────╢ Base      ║      ║     VCC ╟──┤
 |  │     ║ Emitter   ╟──────╢ GND     ║  │
 |  │     ╚═══════════╝      ╚═════════╝  │
 |  │     ╔═══════════╗     ╔══════════╗  │
 │  │     ║  -ESP32-  ║     ║-HLK-PM01-║  │
 |  │     ║           ║     ║          ║  │
 │  │ GND ║ 3V3   VIN ╟─────╢ +Vo (+5V)║  │
 │  │  ╧ ─╢ GND   GND ╟─────╢ -Vo      ║  │
 │  └─────╢ D4        ║     ╚══════════╝  │
 |      ┌─╢ D13   D12 ╟─┐ ┌───── GND      │
 |      │ ║           ║ | |       ╧       │
 |      │ ╚═══════════╝ | | ╔══════════╗  │
 |      │ ╔══════════╗  | | ║ -Servo2- ║  │
 |      │ ║ -Servo1- ║  | | ║          ║  │
 |      │ ║          ║  | └─╢ GND      ║  │
 |      └─╢ Signal   ║  └───╢ Signal   ║  │
 |        ║      VCC ╟──┐   ║      VCC ╟──┤
 └────────╢ GND      ║  |   ╚══════════╝  │
          ╚══════════╝  └─────────────────┘

Breadboard drawing

The image is based on this document which was drawn in fritzing.

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Available http commands

In examples let's assume the esp32 has been issued the ip address 192.168.1.231 on your local network.

Move

Method: HTTP GET.

Move accepts four query parameters

• tilt is a Required parameter for how much in degrees the tower should be tilted (up/down position).
  • Valid values: 0 - 264.
• pan is a Required parameter for how much in degrees the tower should be paned (left/right position).
  • Valid values: 0 - 255
• laser is a Optional parameter for how bright the laser should be where 255 is full on and 0 if off.
  • Valid values: 0 - 255
• blink is a Optional parameter how many milliseconds should pass before blinking. Pass 0 to turn blinking off. Pass 3500 to make the laser blink every 3.5 seconds.
  • Valid values: 0 - 2147483647

Example query

• http://192.168.1.231:5100/move?tilt=101&pan=148&laser=255&blink=1000

Set

Method: HTTP GET.

Set accepts two query parameters

• laser is a Optional parameter for how bright the laser should be where 255 is full on and 0 if off.
  • Valid values: 0 - 255
• blink is a Optional parameter how many milliseconds should pass before blinking. Pass 0 to turn blinking off. Pass 3500 to make the laser blink every 3.5 seconds.
  • Valid values: 0 - 2147483647

Example query

• http://192.168.1.231:5100/set?laser=255&blink=3000

Grid

Method: HTTP GET.

Grid accepts two query parameters

• tilt is a Required parameter for how much in degrees the tower should be tilted (up/down position).
  • Valid values: 0 - 264.
• pan is a Required parameter for how much in degrees the tower should be paned (left/right position).
  • Valid values: 0 - 255

Example query

• http://192.168.1.231:5100/grid?tilt=70&pan=90

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Development

To upload this program firmware over the air (OTA) change the upload-port to 3232. To upload this program firmware using usb change the upload-port to something like COM6, that is if you computer gave the esp32 usb connection the name COM6.

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