Laser range finder project

[LaserDeveloper]

In the next few months there will be another assault on the difficult task of engineering a reasonably priced laser range finder (LRF) for use by hobbyists and robot enthusiasts. This design will use the time-of-flight principle to measure how long it takes for a brief flash of laser light to travel from a laser to a target surface and back to a detector. It will be based on the technology found in the open source DS00 LRF and will probably use a variant of the DS00VQ100 timer/controller chip.

In order for us to develop something that is useful, we need to know more about the potential applications for this LRF and what specifications would make the device a valuable addition to your electronics box of tricks. There's also the issue of determining an acceptable price for the finished product and any suggestions on how to reduce the manufacturing cost would be appreciated.

Many designers who have attempted to make time-of-flight laser range finders have battled with the high speed signal processing and the high cost of components. Whilst we don't have answers to all of the technical challenges (yet) we think that an LRF with a range in excess of 10m and an update rate of more than 50 readings per second will make it useable in scanning systems that can detect obstacles over a wide area or even create three dimensional maps. A longer range laser could be used in amateur UAVs for ground detection but might end up being more expensive.

Please give us your thoughts and constructive criticisms. If there is sufficient interest on this forum then we'll keep you posted about the progress.

[BrentBXR]

I would love to see a project log of this project. out of curiosity what type of distances are we talking?

[LaserDeveloper]

out of curiosity what type of distances are we talking?

The open source DS00 LRF kit comes with two different optical modules, one will measure 50m and the other 100m. However, the DS00 uses some expensive parts to achieve this range - APD, hybrid laser, optical filters, special amplifiers etc.

For the new LRF project we want to use lower cost parts where possible and this will inevitably reduce the measuring range. The big question is, what range should we be trying to reach so that we end up with a useful device?

[Sjaak]

Is a 'show a pic of your protective goggles before starting this project' worth mentioning? Unless you know exactly what you doing I would advise to buy a ready made one :)

Are the lasers in the visible range? Not that it matter much for getting blind; with a visible one you see you notice you are getting blind, with a 'unvisible' you don't know what happened.

[LaserDeveloper]

protective goggles

Eye safety will be an important part of the LRF design. We will aim for class 1 or class 1M power levels so that the device is as safe as possible. At these ratings the laser will not induce any biological damage to the skin or eyes, even if they are exposed for long periods of time. Fortunately, the regulations and design requirements for "eye safe" lasers are well understood so it won't matter if the laser is visible or IR.

[Sjaak]

I assume you know your laser stuff, but just a standard disclaimer :)

[LaserDeveloper]

For those interested in this project it became the AL-01 laser range finder for the Arduino. Project details can be found on the Arduino forum web site.