The six-wheeled delivery robot Scout has bumped into its last obstacle on a sidewalk and is being gradually retired by Amazon. Future delivery drones may descend from the air so they don't get stuck on pesky tree roots.

Amazon began testing the robot in 2019 in Washington state, before expanding to California, Georgia, and Tennessee. The unit is about the size of a cooler and resembles a shorter version of R2D2. It can autonomously follow a delivery route, stop at a customer's house (assuming there are no stairs), and open a hatch so the package can be retrieved.

Scout is autonomous to a point, and it always required a human chaperone/ambassador to accompany it so it didn't go off track and get stuck on things---like other Amazon Scouts.

This isn't quite a full retirement. The Scout will not be taken into the woods and shot, or forced into the risky life of a bomb-defusing robot. Instead, the program is being reoriented.

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"During our Scout limited field test, we worked to create a unique delivery experience, but learned through feedback that there were aspects of the program that weren't meeting customers' needs," said Amazon spokesperson Alisa Carroll.

"As a result, we are ending our field tests and reorienting the program."

According to Bloomberg, there were approximately 400 workers on the project, and nearly all will be moved to other teams, leaving behind a skeleton crew to explore autonomous robots.

Don't think that this means Amazon is placing all its energy in the crazy old concept of human delivery people. The company is still testing drone deliveries in California as part of Prime Air. There are no stairs in the sky.