Background

We have developed a noncontact, robust and lightweight optical Position Sensing
Device (PSD) capable of measuring the angular position of a contrasting edge with a very high accuracy in ambient light. This sensor is highly suitable for self positioning or optical tracking systems embedded onboard ships, aircraft, ROV, UAVs, UGVs, microsatellites and landers. The device is also capable to detect the presence of a thin bar present in its visual field of view.

GPS based self positioning systems are slow and inaccurate. Besides, they do not allow moving objects to be tracked and may suffer from signal dropouts.

→ Our sensor can operate under many lighting conditions, within a spectral range that can be selected from UV to terahertz. It is relatively insensitive to contrast within a large illuminance range. The system is simple, easy to set up, and satisfies both civilian and military norms. It is also suitable for applications requiring a wide field of view since many (low cost and lightweight) sensors of this kind can be mounted adjacent to one another

Benefits

Development status

We built a sensor prototype that measures the position of a contrasting object with a high accuracy, within a wide illuminance range and for a wide range of contrast. The sensor was tested onboard a 100-gram aerial robot that achieved

Applications

• Autopilot for UAVs, MAVs, ROVs, UGVs, and spatial vehicles: drift free system stabilizer, precise hovering and precise docking.
• Drift correction: can compensate for the natural drift of miniature IMUs
• Cable detector for manned or unmanned aerial and underwater vehicles
• Automatic crash avoidance