3 Raspberry Pi Zero w/Camera Setup

Steps to program the Raspberry Pi Zero computers to capture and store images:

1. Obtain necessary cables/connectors:

  • USB 2.0 to microSD card reader (to image SD card on a PC)
  • USB 2.0 microUSB male to USB female adapter (to connect keyboard with Pi)
  • Keyboard with USB 2.0 wire
  • Micro HDMI male to HDMI female adapter & HDMI cable (to connect monitor with Pi) or micro HDMI to HDMI cable

2. Install operating system:

Raspberry Pi Imager

Figure 3.1: Raspberry Pi Imager

  • Use microSD card reader to mount SD card onto a PC
  • Download and open Raspberry Pi Imager
    • Choose OS → Raspberry Pi OS (Other) → Raspberry Pi OS Lite (32-bit)
    • Choose Storage → Drive referring to microSD card
    • Optional: Gears →
      • Set hostname (name of the pi on your wifi network that you ssh [pi_name]@[IP Address] into)
      • Enable ssh
      • Set username and password (user login information to access the pi)
      • Set locale settings (e.g., America/New York & us)
    • Write
  • Disconnect and insert formatted microSD card into Pi
  • Connect Pi to keyboard, monitor, and power source
  • Once connected to power, Pi automatically turns on

2. Login with default or already specified login information:

  • raspberrypi login: pi
  • password: raspberry

3. Configure Pi settings: sudo raspi-config

  • Use arrow keys and Enter to navigate
  • 1 → S1 Connect to wifi
    • SSID: wifi network name
    • Passphrase: wifi password
  • 1 → S3 change pi password
  • 1 → S4 change pi name (not login)
  • 3 → I1 enable camera attachment
  • 3 → I2 enable remote access (ssh)
  • 5 → L2 set timezone
  • Finish (type y when asked if you want to reboot)

4. Add static IP address for remote access: https://raspberrypi-guide.github.io/networking/set-up-static-ip-address

5. Continue programming directly or remotely access the Pi through terminal from another PC:

ssh login_name@[IP address]
password:

6. Make a folder/directory named ‘still’ to hold images: mkdir still_[xxx]

  • Note: [xxx] refers to the login name of the Raspberry Pi associated with the iLAM

7. Make a directory named script to hold scripts: mkdir script_[xxx]

8. Write a script using a text-editor (e.g., nano) named still_[xxx].sh: sudo nano ./script_[xxx]/still_[xxx].sh and write the following text:

#!/bin/bash
DATE=$(date +"%m%d.%H%M")
sudo raspistill -o /home/$USER/still_$USER/$USER.$DATE.jpg
  • This script will take images and save them along w/ metadata into the still_$USER directory:
    • (Line 1) necessary for any bash file with instructions
    • (Line 2) sets the format for the date and time in the file name
    • (Line 3) command for pi to take a photo and store it with specified file name/location.
  • Hit control^X to exit (type y when asked if you want to save)

9. To automatically upload/copy images into a remote directory, you may (A) use scp to upload each image after it’s taken, or (b) mount a remote directory and then copy each image.

  • ssh-keygen and ENTER to generate a new SSH key to enable a custom script to automatically upload images without requiring a password input

  • ssh-copy-id -i ~/.ssh/id_rsa [remote_PC_hostname]@[remote_PC IP address]

  • Input password for remote_PC

  • Option A: Add the following line to the end of still_[xxx].sh:

scp /home/$USER/still_$USER/$USER.$DATE.jpg [remote_PC_hostname]@[remote_PC IP address]:[directory that you want images saved into]/
  • Option B: Add the following lines to the end of still_[xxx].sh:
sleep 10
scp /home/$USER/still_$USER/$USER.$DATE.jpg /home/$USER/mount_$USER/

10. Schedule the imaging script to run periodically with crontab:

  • Access the crontab file
sudo crontab -e
  • Select the first option to edit the crontab in nano
  • Copy the following to the bottom of the file:
*/2 *  *   *   * sh /home/$USER/script_$USER/still_$USER.sh 2>&1

  • This tells the pi to execute the still.sh file every 2 minutes (the order is minute, hour, day of month, month, day of week). When setting up a new crontab, always run it past crontab.guru!

  • control^X to exit (type y when asked if you want to save)

11. Access Raspberry Pi image files on your PC:

  • Even if your iLAM/Pi is programmed to upload files to a remote computer over Wifi, at the end of every experiment, we recommend verifying that all images were properly uploaded/transferred. To remotely download images, you may:

  • Option A: Download images via Command line

    • Log in to the Linux/Powershell on your laptop

      scp pi@[IP address]:~/still_[xxx]/*.jpg ~/[target directory]`

  • Option B: Download images via a free file transfer program (FTP) like FileZilla

    • Open FileZilla: In Site Manager, choose New site

    • Protocol: SFTP - SSH File Transfer Protocol

    • Host: [IP Address of Raspberry Pi]

    • Logon Type: Normal

    • User: [Pi login name]

    • Password: [Pi login password]

    • Connect

Trouble-shooting

-raspistill will not take a picture and returns** *failed to open vchiq instance:

  1. Verify that the camera is connected and the ribbon cable is not damaged:

    vcgencmd get_camera

  2. Determine if the camera or the still_[xxx].sh script is the issue:

    raspistill -o /home/$USER/test.jpg

  3. Modify permissions of the camera: sudo chmod777 /dev/vchiq

A Linux reader is required to read the Raspian imaged SD card, when plugged into a Windows PC. Linux Reader is a free option. Instructions can be found here.

Tips:

  • Useful Linux commands:

    • * wildcard (e.g. *.jpg == all jpeg files)
    • control^A bring cursor to beginning of line
    • control^E bring cursor to end of line
    • control^C kill process
    • clear clear all previous text from terminal
    • ls list all contents in current folder
    • cd directory_path change to named folder
    • cd ~ go to home directory
    • cd .. go up one folder level
    • cd - go back to last folder
    • mkdir dir_name create EMPTY folder (directory)
    • rmdir dir_name remove EMPTY folder
    • rm file_name remove a file
    • rm -f file_name remove a file without asking for permission
    • rm -r dir_name recursively remove all files from folder
    • rm -rf dir_name forcefully remove all files from folder
    • ren name_1 name_2 rename something to something else
    • cp file_1 file_2 copy file_1 to file_2, creates duplicate. note: if file_2 exists will overwrite (NO warning)
    • cp -r dir_1 dir_2 copy folder and its contents
    • nano file_name make named file and open text editor
    • sudo reboot reboot pi
    • sudo shutdown now safely shutdown pi (reboots when plugged in again)