Stanford Cart Slider Modification by Hans Moravec
During the late 1970s, Hans Moravec at Stanford University extended the Stanford Cart, originally built by James L. Adams in the 1960s, with a sliding camera mount, enabling the robot to navigate autonomously across a chair-filled room in 1979 using stereo vision, a milestone in autonomous vehicle research.
Background
Getting a robot to move through the real world without hitting things is harder than it sounds. In the 1960s and early 1970s, most mobile robots either followed physical guides, like a wire embedded in the floor, or operated in environments stripped of anything unexpected. The moment you put something in the way, they failed.
The Stanford Cart, originally built by James L. Adams at Stanford University in the 1960s, was one of the few machines of its era that tried to use cameras rather than guides. Its original purpose was actually to study whether a rover could be controlled remotely from Earth despite a time delay, the kind of delay you would get communicating with something on the moon. It could trundle around, but it could not see well enough to avoid obstacles on its own. The camera gave it one view, and one view is not enough to judge how far away something is.
Stereo vision, the technique humans use unconsciously when they judge distance, requires two slightly different images of the same scene. Comparing where objects appear in each image lets you calculate depth. A fixed camera cannot do that by itself.
What happened
Hans Moravec, working at the Stanford Artificial Intelligence Laboratory, modified the Cart by adding a sliding camera mount. The camera could shift sideways in small steps, taking a photograph at each position. Nine images from nine positions along the slide gave the Cart something close to what two eyes give a person: enough variation to estimate how far away each obstacle was.
The processing was done on a KL10 processor running at 2.5 MIPS (millions of instructions per second). That was not fast. After each short movement the Cart would stop, take its photographs, and spend a long time working out where everything was and what to do next. The room-crossing in 1979 took around five hours to complete.
What it completed was a crossing of a room scattered with chairs, moving roughly 20 metres without hitting anything and without anyone touching the controls once the run had started. The Cart would advance a metre or so, stop and think, then move again. It was slow enough that watching it must have been more like watching a clock than watching a vehicle. But it got from one side to the other on its own, using nothing but the images from its camera to understand the space around it. Moravec documented the full system and its results in his Stanford PhD thesis, published in 1980.
The date of that run is recorded only by year. Attempts to pin it to a specific month or day trace back to sources that do not hold up, so 1979 is as precise as the evidence allows.
Why it mattered
The Stanford Cart's 1979 room-crossing demonstrated that a robot could plan and execute collision-free movement through a cluttered, real-world environment using only visual input, without human intervention beyond initial setup. It was one of the earliest demonstrations of autonomous navigation using computer vision rather than structured environments or physical guides. Moravec's work on the Cart directly informed subsequent research on stereo vision, obstacle avoidance, and probabilistic reasoning in robotics.
People
Hans Moravec, James L Adams
Organisations
Sources
- Obstacle Avoidance and Navigation in the Real World by a Seeing Robot Rover (PhD Thesis).Stanford University / Carnegie Mellon University Robotics Institute.Primary source
- The Stanford Cart.Stanford University.Official
Cite this page
AI Achievements. (1979). Stanford Cart Slider Modification by Hans Moravec. Retrieved 2026-08-22, from https://achievements.ai/milestone/stanford-cart-with-a-slider-by-hans
@misc{achievements_stanford_cart_with_a_slider_by_hans,
title = {Stanford Cart Slider Modification by Hans Moravec},
author = {{AI Achievements}},
year = {1979},
url = {https://achievements.ai/milestone/stanford-cart-with-a-slider-by-hans}
}