Skip to content

part-specs: obstacle-avoidance camera (OmniVision OV5647) #28

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
makers-pet merged 1 commit into from
Jul 22, 2026
Merged

part-specs: obstacle-avoidance camera (OmniVision OV5647) #28

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
160 changes: 160 additions & 0 deletions contributions/part-specs/OsakaTX/obstacle-avoidance-camera-ov5647.md
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,160 @@
# Obstacle Avoidance Camera — OmniVision OV5647

> **Contributor:** OsakaTX
> **Added:** July 18, 2026
> **BOM entry:** "Obstacle avoidance vis camera — OV5647 5M MIPI 16-pin cable, 130 deg, no IR-cut filter" (added to `BOM.md` in upstream commit `6b8f59c`, 2026-07-18)
> **Source:** The OV5647 is the sensor behind the original Raspberry Pi Camera Module 1. Specifications below are taken from the official Raspberry Pi camera documentation, which publishes the sensor-level parameters. The BOM item pairs this sensor with a wider-angle (≈130°) lens and removes the IR-cut filter for night-vision / near-IR obstacle detection.

This file complements the main `README.md` part-specs index. It documents the newly
sourced obstacle-avoidance camera so the camera has the same level of part-spec
coverage as the LiDAR, ToF, IMU, and other sensors.

---

## Sensor Identification

| Parameter | Value |
|---|---|
| **Sensor** | OmniVision OV5647 (same die as Raspberry Pi Camera Module 1) |
| **Type** | CMOS rolling-shutter image sensor |
| **Optical format** | 1/4" |
| **Still resolution** | 5 megapixels (2592 × 1944) |
| **Pixel size** | 1.4 µm × 1.4 µm |
| **Sensor image area** | 3.76 × 2.74 mm |
| **Color filter array** | Bayer RGB |
| **Output interface** | MIPI CSI-2 (2-lane D-PHY) |
| **Control bus** | I²C (SCL/SDA), typically 400 kHz |
| **Supply** | 2.8 V (AVDD, analog) + 1.8 V (DOVDD, I/O; 1.7-3.0 V range) + 1.5 V (DVDD, core, internal regulator); module-level 3.3 V via the CSI connector |

> **Note on the sensor identity:** The BOM entry names "OV5647" explicitly. The
> Raspberry Pi Camera Module 1 (the best-known OV5647 carrier) is listed in the
> official Raspberry Pi camera comparison table with the parameters reproduced
> above. The OOMWOO BOM item is **not** the stock Raspberry Pi Camera Module 1 —
> it is an AliExpress "night vision" module that uses the same OV5647 die with a
> third-party wider-angle lens and no IR-cut filter. Sensor-level specs transfer;
> lens-level specs (focal length, FoV, F-stop) do **not** and are given separately
> below from the BOM entry.

---

## Module-Level Specs (BOM Entry)

From `BOM.md` (upstream commit `6b8f59c`, 2026-07-18):

| Parameter | Value |
|---|---|
| **Sensor** | OV5647, 5 MP |
| **Cable** | 16-pin MIPI CSI-2 FPC |
| **Field of view** | ~130° (wide-angle lens, third-party) |
| **IR-cut filter** | **None** (night-vision / near-IR variant) |
| **Purpose** | Advanced obstacle avoidance |
| **Retail price** | $6–7 |
| **Search term** | "ov5647 night vision" — [AliExpress](https://www.aliexpress.us/wholesale-ov5647-night-vision.html) / [Amazon](https://www.amazon.com/s?k=ov5647+night+vision) / [eBay](https://www.ebay.com/sch/i.html?_nkw=ov5647+night+vision) |

The "no IR-cut filter" variant is the key difference from the standard Raspberry
Pi Camera Module 1: removing the IR-cut filter lets near-infrared light reach the
sensor, which is what makes these modules usable as a low-light / active-IR
obstacle camera when paired with an IR illuminator.

---

## CSI-2 Connector Pinout (16-pin FPC, 1.0 mm pitch)

> ⚠️ **Connector caveat:** The BOM entry specifies a **16-pin** cable. The
> standard Raspberry Pi CSI-2 connectors are **15-pin** (flagship Pi ≤4, CM1–CM4
> IO boards) or **22-pin** (Pi Zero, Pi 5, CM5 IO board). A 16-pin 1.0 mm FPC is
> a common third-party OV5647 module format and typically carries the same
> MIPI CSI-2 + I²C + power signals as the 15-pin Raspberry Pi connector, often
> with one pin reserved or repurposed for an on-module IR illuminator enable.
> The exact 16-pin assignment is module-vendor-specific; verify against the
> module's silkscreen before wiring. The 15-pin Raspberry Pi pinout is reproduced
> below as the reference since the signal set is identical.

### Reference: 15-pin CSI-2 connector (Raspberry Pi, Amphenol SFW15R-2STE1LF)

Direction is from the SBC's perspective. I²C lines are pulled up to 3.3 V on the
SBC side.

| Pin | Name | Description | Direction / Type |
|-----|------|-------------|------------------|
| 1 | GND | Ground | Ground |
| 2 | CAM_DN0 | D-PHY lane 0 (negative) | Input, D-PHY |
| 3 | CAM_DP0 | D-PHY lane 0 (positive) | Input, D-PHY |
| 4 | GND | Ground | Ground |
| 5 | CAM_DN1 | D-PHY lane 1 (negative) | Input, D-PHY |
| 6 | CAM_DP1 | D-PHY lane 1 (positive) | Input, D-PHY |
| 7 | GND | Ground | Ground |
| 8 | CAM_CN | D-PHY clock (negative) | Input, D-PHY |
| 9 | CAM_CP | D-PHY clock (positive) | Input, D-PHY |
| 10 | GND | Ground | Ground |
| 11 | CAM_IO0 | GPIO (typically power-enable, active high) | Bidirectional, 3.3 V |
| 12 | CAM_IO1 | GPIO (typically clock / LED) | Bidirectional, 3.3 V |
| 13 | SCL | I²C clock | Bidirectional, 3.3 V |
| 14 | SDA | I²C data | Bidirectional, 3.3 V |
| 15 | 3V3 | 3.3 V supply | Output |

**Likely 16-pin module mapping (hypothesis, verify on-silkscreen):** the 16th pin
on night-vision OV5647 modules is commonly used for an on-board IR-LED
illuminator enable (active-high) or an extra GND. Treat this as unverified until
the specific module is inspected.

### Compute Module 5 / Pi 5 (22-pin) connector

The OOMWOO BOM lists both a Raspberry Pi CM4 ≥2 GB (primary, ~$62.50) and a
CM5 ≥2 GB (~$72.50) as compute-module options. On a CM5 build, the camera
attaches through the 22-pin CSI-2 connector (Amphenol F32Q-1A7H1-11022).
It is a superset of the 15-pin connector: same lane-0/lane-1 + clock + I²C +
power signals, plus lane 2 and lane 3 pairs for 4-lane sensors. The OV5647 is a
2-lane sensor, so only the lane-0/lane-1 pins are used; the extra lanes are
no-connects. The full 22-pin pinout is in the Raspberry Pi mechanical drawings /
Product Information Portal referenced below.

---

## Host-Side Interface (OOMWOO compute module)

- **Compute module:** Raspberry Pi **CM4 or CM5 ≥2 GB** (`BOM.md` lists CM4 ≥2 GB
as primary at ~$62.50 and CM5 ≥2 GB as the alternative at ~$72.50; the ≥4 GB
options were dropped 2026-07-18 in commit `19ec1c2`). The CSI connector differs
by choice: 15-pin on the CM4 IO board, 22-pin on the CM5 IO board.
- **Camera interface:** MIPI CSI-2 receiver on the compute module's SoC (BCM2711
on CM4, BCM2712 on CM5), 2 lanes sufficient for the OV5647's peak data rate.
- **Driver:** `ov5647` in the Raspberry Pi / libcamera stack; the sensor is a
long-supported first-party Raspberry Pi sensor.
- **Control:** I²C for sensor register configuration; `CAM_IO0` for power-enable.

---

## Why a No-IR-Cut OV5647 for Obstacle Avoidance

- The OV5647's Bayer photodiodes are sensitive into the near-IR (~1000 nm); the
IR-cut filter on the standard Raspberry Pi Camera Module 1 blocks this band to
produce natural color.
- Removing the IR-cut filter lets the module image in near-darkness when paired
with a 940 nm (or 850 nm) IR illuminator — the same approach used by Roborock's
own "Reactive AI" obstacle cameras and by commercial night-vision CSI modules.
- At ~$6–7 retail this is the cheapest obstacle-avoidance sensing option in the
BOM, well below the VL53L7CX ToF ($8–15) and complementary to the 2D LiDAR
(which gives range but not object classification).

---

## What We Still Need

| Item | Status |
|---|---|
| Exact 16-pin FPC pinout for the specific AliExpress module | ❌ Needs silkscreen inspection of the chosen module |
| Lens focal length / F-stop / distortion profile for the 130° variant | ❌ Vendor-specific, not in the BOM entry |
| IR illuminator: on-module vs. external, wavelength (850 vs. 940 nm), drive | ❌ Needs module inspection |
| Module PCB dimensions / mounting-hole pattern | ❌ Needs physical measurement |
| Power consumption (sensor + illuminator) | ❌ Needs measurement |
| Confirmed libcamera / `ov5647` driver compatibility with the no-IR-cut module | ❌ Needs runtime test on CM5 |

---

## References

- [Raspberry Pi camera documentation — hardware specification table](https://www.raspberrypi.com/documentation/accessories/camera.html) (CC BY-SA 4.0) — source for the sensor-level specs (resolution, optical format, pixel size, image area).
- CSI connector pinouts and Amphenol part numbers (15-pin `SFW15R-2STE1LF`, 22-pin `F32Q-1A7H1-11022`): Raspberry Pi mechanical drawings / Product Information Portal ([pip.raspberrypi.com](https://pip.raspberrypi.com)) and the CM4 IO board / Raspberry Pi 5 schematics, cross-checked against the [Arducam CSI pinout reference](https://docs.arducam.com/Raspberry-Pi-Camera/raspberry-pi-camera-pinout/).
- [OOMWOO BOM.md — obstacle avoidance camera entry](https://github.com/makerspet/oomwoo/blob/main/BOM.md) (commit `6b8f59c`, 2026-07-18).
- [OmniVision OV5647 datasheet (public mirror)](https://cdn.sparkfun.com/datasheets/Dev/RaspberryPi/ov5647_full.pdf) — full preliminary specification: power rails (AVDD 2.8 V, DOVDD 1.7-3.0 V, DVDD 1.5 V), registers, pinout.