Design and Implementation of a Laser Level Detector

Student: Geoffrey Cook

Supervisor: Peter Sutton

Category: Engineering Thesis Project - Computer Systems

The project began with the concept of building an electronic reader for a laser level (height) measurer. This idea was expanded to embrace a variety of different uses throughout the construction industry, where low-precision alignment may be required as part of a construction process.

The device is designed to substitute for the ‘human’ (subject to error) element in reading the position of a laser beam on a scale. Instead, the detector automatically determines this position, and displays it to the user.

Such a detector would only require low-resolution reading: similar to that which a human eye could perceive. Other specifications were developed to make this product as ‘useable’ as possible, such as the required length, the sampling or reading rate, the display requirements, current limits and a component budget. These limitations were imposed to mimic real-world design constraints.

The hardware concept for the sensors was quite simple: an array of detectors, with a digital output fed into a row of shift registers. The shift registers could be ‘latched’ to lock in the detector data, and then ‘clocked’ to feed the data back to a microcontroller. The controller module hardware involved a display to be multiplexed, a microcontroller (in-circuit programmable), a serial connection and a power supply.

The embedded software was responsible for coordinating, reading and interpreting the hardware. It would calculate the position of the laser beam using the data fed back by the shift registers. The display would be updated with this value, which was also sent to an optional connected PC via a serial connection. The PC software reads the data and displays it on the PC.

The solution was the ‘Laser Level Detector’ – a device that reads the position of a laser beam on a ruler and displays the value.

Thesis Document (PDF)