The Cutting-Edge IT & Electronics Comprehensive Exhibition (CEATEC) threw open its doors to thousands of visitors eager to sample gizmos they will be using in future.
The highlight of the tech fair for many is Japanese carmaker Nissan, which showcased self-driving cars that allow the driver to kick back and take their eyes off the road.
A series of sensors constantly monitors the road and objects nearby, turning the wheel automatically to avoid obstacles. "Most accidents are caused by human error," said Nissan in a release.
Vehicle makers are working to integrate automobiles and houses, with the vehicle able to power the home especially useful in times of blackouts caused by natural disasters.
Honda is showing off a mock installation in which a motorbike powers a gigantic kettle.
"Welcome to the future garage that Honda has designed. This is how automobiles and communities will be connected," said Honda president Takanobu Ito.
Augmented reality is a big theme at the fair in Chiba, with Pioneer showcasing new navigation systems that can direct drivers to vacant parking spots with signs that appear in front of them.
Car electronics maker Clarion has a chatty sat-nav capable of carrying on a conversation with the driver, and reminding him or her to take a break.
"You have driven for a long time. How about a cup of coffee? There is a nice cafe nearby that offers tasty sweets," it says.
The system, powered by Google, also finds restaurants by price bracket, offering up suggestions when the driver tells it: "I would like a place where I can have lunch for 1,000 yen ($10)."
Many firms have their eyes on the 2020 Tokyo Olympics and the possibilities their technologies could offer to visitors.
Chief among them is NTT Docomo, whose augmented reality glasses can translate a menu in real time.
Its latest development combines cameras, computers and know-how to give the wearer a different view of what they are looking at.
One function of the gizmo overlays the wearer's first language onto unfamiliar text, making signs and menus instantly understandable a boon to travellers in Japan, where foreign-language menus are not commonly found off the tourist trail.
"Character-recognition technology enables instant language translation for users travelling abroad and reading restaurant menus and other documents," Docomo said in a statement, as it showcased the gadget.
Another application turns any flat surface into a touchscreen, with a finger ring relaying positioning information to the device that lets wearers "touch" tags that only they can see, perhaps to perform an Internet search.
NTT Docomo said a user wearing the glasses and ring set could dispense with the need to carry a laptop or a tablet.
Other uses include facial recognition that could look up someone's identity and job title from a smartphone's directory.
More than 580 companies are taking part in the trade show, which has brought exhibitors from 18 countries and territories. The show runs until Saturday.
For details of the latest launches and news from Samsung, Xiaomi, Realme, OnePlus, Oppo and other companies at the Mobile World Congress in Barcelona, visit our MWC 2025 hub.