High dynamics and precision optical measurement using a position sensitive detector (PSD) in reflection-mode:...

Area of Science:

• Microrobotics and Sensor Technology

Background:

• Position Sensitive Detectors (PSDs) offer advantages in positioning accuracy and response time compared to classical camera sensors.
• Previous microrobotic control systems were limited by the slow response of camera sensors, necessitating expensive high frame rate cameras for precise control.

Purpose of the Study:

• To comparatively analyze the performance of a fast, custom-made Position Sensitive Detector (PSD) system against a slow video camera for micro-object tracking.
• To develop and test a low-cost, PSD-based embedded circuit for enhanced microrobotic control.

Main Methods:

• A comparative analysis was conducted using a custom-made fast PSD system and a conventional video camera to track a diffuse-reflectivity object on a pneumatic microconveyor (Smart-Surface).
• A custom, low-cost PSD-based embedded circuit was developed and tested, optically integrated with a camera via a beam splitter.
• A stroboscopic light source was employed to enhance system resolution.

Main Results:

• The custom PSD system demonstrated a fast response time exceeding 500 frames per second.
• The PSD system exhibited good linearity in its performance.
• The results indicate the feasibility of using PSDs for precise and rapid tracking in microrobotic applications.

Conclusions:

• The developed PSD system provides a fast and accurate solution for micro-object tracking, overcoming limitations of traditional camera sensors.
• This low-cost PSD-based system enables future closed-loop control for microrobotic applications, previously hindered by system dynamics.
• The findings suggest PSDs are a viable alternative for high-performance sensing in microrobotics.