Apps using Apple LiDAR can be quite a timesaver for interior design, floor plans
If your idea of a laser scanner is a camera-like device mounted on a tripod, a device that is un-Godly expensive,
à la Hexagon or Faro system, you may be surprised to learn you have a laser scanner in your pocket. That
is if you have an iPhone 12 Pro, iPad Pro 2020 or later models.
Apple has shrunk LiDAR to fit into late model iPhone or iPads. LiDAR, short for Light Detection And Ranging,
works by emitting light (radiation) and calculating the distance by the time it takes to receive its bounce, resulting in points on a subject a known distance and direction from the source. But the difference between Apple’s implementation for consumers and professional application of LiDAR are remarkably different.
For one thing, Apple’s LiDAR does not have mm accuracy. Measurements are plus or minus one inch. It can’t scan very far, either. Its range is limited to about 5 m. It was useful for measuring my garage; it was useless for measuring the width of an ice hockey rink.
How Does LiDAR Work?
Timing the roundtrip of light from objects meters away takes a very precise stopwatch,
or 3.3e-8 seconds
for an object 5 m away. Sending a series of laser pulses scanning horizontally and vertically produces many points in space.
Professional LiDAR systems have a laser rotating about a horizontal axis,
moving the laser up and down, while simultaneously spinning it about a vertical
axis for a 360° panorama. This requires many moving parts and precise
tolerances. By comparison, the LiDAR system in the iPhone has no moving parts
and its field of view (FoV) is limited.
Apple’s LiDAR is not to be confused with its True Depth sensor, which
sends a single pulse of infrared light and is used for used for mapping your
face to let you log in.
Velodyne, the leader in professional LiDAR systems, maker of the coffee-can size rotating scanners on autonomous test vehicles and robotaxis, uses a mirror to direct the laser up and down while rotating the laser about the vertical axis. It can cost $75,000.
And you thought the iPhones were expensive?
Clearly, if LiDAR is to be considered practical for consumer and industrial use, it has to have less moving parts and be smaller and cheaper.
Early Days: Self Driving Cars
You might consider Microsoft’s Kinect, launched 2010, a first in LiDAR-like implementation for consumers. This gaming system was only able to distinguish an object’s depth within 1 centimeter and its height and width to within 3 mm
and yielding blurry images. But if all that was needed was to detect gross human movement to let you play virtual tennis or golf,
a blurry image is sufficient.
In 2020 Apple proudly unveiled the iPhone 12 Pro with built-in true LiDAR. Gamers were quick to adopt
LiDAR but most everone else wondered what it was good for. Those used to professional LiDAR saw no comparison with Velodyne-type systems that were able to generate point clouds and see off to the horizon.
But Velodyne, the leading maker of professional LiDAR systems, was under considerable price pressure. The
automobile industry and automotive startups in particular were demanding the accurate sensing
only LiDAR can provide. Only a few luxury automobiles could absorb the cost of all the sensors
full (Level 5) autonomy requires. By 2020, a panoply of smaller, less expensive LiDAR units had emerged from Ibeo, Sense, and Ouster.
Professional Apps That Use Apple LiDAR
A small number of useful tools has emerged that use Apple’s LiDAR for professional use.
The timing could not have been better as I am in the process of renovating my garage and kitchen.
An interior designer has been retained.
“We use CAD,” said the interior designer. Armed with a CAD designer and
a tape measure, she delivered a PDF of a floorplan a month later. A little
behind the state of the art, I thought, but an improvement over a room addition
that went up a few years ago withour even a sketch.
A Floor Plan as if by Magic
So, imagine my delight in finding magicplan, which after a free download from the Apple Store, let me produce a floor plan simply by walking around and pointing to walls and corners with my iPhone camera. Admittedly,
the first attempt missed a corner and made a triangular office, but the second
attempt made a perfectly rectangular, dimensioned, accurate floor plan in about
15 minutes.
It had taken our interior designer team an hour to measure the room and several more hours to make a CAD drawing.
In the hands of an expert, it took only 7 minutes to map out a furnished office, as claimed on the magicplan website.
SiteScape
SiteScape was one of the first applications that used LiDAR from a iPhone.
SiteScape came to our attention after its acquisition by Faro. SiteScape uses a combination of photogrammetry (to provide a visual image) and LiDAR (to provide accuracy). The app can export in several point cloud formats but
does not make surface models or extract objects automatically, such as vector lines or walls.
Canvas
Canvas (of Canvis.io) is another measurement app that lets you use the LiDAR on the Apple devices and can export CAD and BIM models. Canvas
makes 3D models for free by scanning a room with a late model iPhone device. While the 3D model can be a little splotchy, more like an impressionist painting than high resolution still or video, it is still a big improvement over the jumbled mess
that is a point cloud. It is measurable, unlike the 3D photos made using photogrammetry
exclusively. And, very importantly, it is free.
You will have to pay (per sq. ft., an odd pricing model for SasS but fitting
of the industry) for PDF, 2D CAD or BIM models
that Canvas promised to deliver in 24 hours.
Canvas was not tested for this article.
Polycam
Polycam claims to be the most popular LiDAR scanning app in the Apple Store. Polycam also combines photogrammetry with LiDAR.
“LiDAR and photogrammetry have different strengths and complement each other really nicely, says Elliott Spelman, co-founder of Polycam. “While LiDAR is incredibly fast and great for scanning spaces, Photo Mode can capture objects with wonderful detail and precision.”
Polycam was not tested for this article.
AI Sees Things
Magicplan, SiteScape, Canvas and Polycam are to be commended for making LiDAR accessible and useful, allowing the accuracy of LiDAR to be put to immediate use, saving chunks of time in the workflow – rather than disrupting a workflow. Waving and clicking on an iPhone to make floor plan fits neatly into an existing interior design workflow, whereas
professional laser scanning could blows up the workflow. The use of AI, such as with SiteScape, is also welcome as it can recognize walls, windows, doors from a cameral view.
