PiCam

Tilt-Pan autonomous camera for timelaps acquisition based on a Raspeberry-pi.

Concept

The first prototype proved the feasibility. It was based on a tilt-pan module (2x SG90 micro-servo) + raspberry-pi camera v1 with CS lens mount.

http://imagizer.terre-adelie.org/2016-08-02-Vesteralen/page3/22h23m39-NIKON_D5100.jpg

Some resulting videos are: http://video.terre-adelie.org/2016/2016-08-04-Melbu/video_4.mp4

Basis

The new basis is made of 9x9mm beech wood sticks (hetre) + 3d printed basis, RPi holder and servomoter holder. The scheme is available and here is a photo … http://imagizer.terre-adelie.org/2016-11-06/11h02m45-NIKON_D800.jpg

PWM generator

“Servo Pi - PWM Controller” from Kubii, actually a PCA9685 PWM I2C controler, 16 channels, 12 bits each (4096 values).

Panorama servo

DSS-M15S from DFRobot.

PWM frequency: 300 Hz,

valeur		deg
525		98
550		97
600		90
700		80
800		69
900		59
1000		48
1100		38
1200		27
1300		16
1400		5
1500		-5
1600		-16
1700		-27
1800		-37
1900		-47
2000		-57
2100		-67
2200		-77
2300		-87
2400		-98
2500		-108
2600		-119
2700		-130
2800		-140
2900		-150
3000		-160
3100		-171
3200		-180
3300		-190
3350		-195

Those are raw values. PWM values needs to be converted in µs (300Hz, 4096 steps …) but the data look rather linear which is great. To simplify, we have a linear behavour:

Timing		angle
420 µs		98°
2710µs		-195°