PiPan Cam

A set of simple scripts used to control a pan-tilt camera setup on Raspberry Pi running pi-blaster and optionally with motioneye.

Prerequisites

• Raspberry Pi with a Camera (eg. this)
• a pan-tilt setup: platform (you google it) and servos (eg. SG90)
• installed pi-blaster

Features and usage

There are two main scripts, which do the work ...
Their job is to move the servos while watching limiting values and to keep track of the current position.

pipan_set.sh

This script sets a specific position of the camera according to passed arguments in PWM %.

But first change the script with your defaults:
(You have to set the pins used for your servos and determine the limiting values where servos can reach - simply by shifting small steps.)

 ENABLED=1              # enables pi-blaster calls (set to 0 for testing)
 myfile="./pipandata"   # file storing current position
 vertical="0.13"        # default vertical position
 horizontal="0.2"       # default horizontal position
 v_pin=18               # pin for vertical servo
 h_pin=17               # pin for horizontal servo
 v_max="0.2"            # vertical max value (down for me)
 v_min="0.055"          # vertical min value (up for me)
 h_max="0.285"          # horizontal max value (left for me)
 h_min="0.06"           # horizontal min value (right for me)

Example

 sh pipan_set.sh 0.12 0.2

pipan_step.sh

This script moves the camera by steps according to passed arguments.
Use positive and negative whole numbers.

But first change the script with your defaults:
(two more than in previous script)

 v_step="0.005"         # one vertical step
 h_step="0.005"         # one horizontal step

Example

 sh pipan_step.sh 2 -5 

That would move my camera two steps down and five steps right (camera view).

---

The second set of scripts is similar, just use input in degrees.

pipan_set_dg.sh

This script sets a specific position of the camera according to passed arguments in (relative) degrees.
Use values 0 to 180 (or according to your defaults).

But first change the script with your defaults:
(two more than in first script)

 dg_min="0"             # degrees min value
 dg_max="180"           # degrees max value
 deci="4"               # decimals for rounding the result [internal]

Script actually re-maps your min/max pwm values to min/max degrees.

Example

 sh pipan_set_dg.sh 90 90 

That would move both servos in the middle of their range.

pipan_step_dg.sh

This script moves the camera by steps in (relative) degrees.
Use positive and negative whole numbers.
[Note: script is currently not very precise]

But first change the script with your defaults:
(two more than in first script)

 dg_min="0"             # degrees min value
 dg_max="180"           # degrees max value
 deci="4"               # decimals for rounding the result [internal]

Example

 sh pipan_step_dg.sh 0 8 

That would move my camera eight degrees left (camera view).

Notes

Don't forget to make the scripts executable:

 chmod +x script_name.sh

You'll need bc installed:

 sudo apt-get install bc

If you run into problems with starting pi-blaster like this, this, or this ... You may have to create the default config with:

 touch /etc/default/pi-blaster

Consider powering the servos from an external source and not from the Pi ... especially if you intend to move something heavier (like a bigger camera maybe).

Usage with motioneye

Current (2016/07/06) version of motioneye only offers a limited way of interfacing external/custom commands... via action buttons - see here.
And you can use this to call your scripts, which move the camera simply by clicking overlay buttons within the camera view :)

I've set that up using the scripts in examples folder like this:

 sudo cp <.yourfolder.>/PiPan_Cam/examples/pipan_go_home.sh /etc/motioneye/lock_1
 sudo cp <.yourfolder.>/PiPan_Cam/examples/pipan_step_left.sh /etc/motioneye/light_on_1
 sudo cp <.yourfolder.>/PiPan_Cam/examples/pipan_step_right.sh /etc/motioneye/light_off_1
 sudo cp <.yourfolder.>/PiPan_Cam/examples/pipan_step_down.sh /etc/motioneye/alarm_on_1
 sudo cp <.yourfolder.>/PiPan_Cam/examples/pipan_step_up.sh /etc/motioneye/alarm_off_1

As of this update, there are new action buttons available - arrows. So you can now rename the scripts: liht_on_1 -> left_1 etc. and move the camera with corresponding arrow buttons.

License

MIT License (MIT) - see here

Change Log

v 1.1 - Jul 08, 2016

• two more scripts - for movement by degrees
• readme update

v 1.0 - Jul 06, 2016

• Initial version

Future plans / TODOs

• moving by degrees and to a specific degree
• precision of movement by degree steps
• optimization?