The compact autonomous robot with ASPINA In-Wheel motors works safe in narrow aisles

A number of companies are working to commercialize autonomous service robots that can travel around stores and offices with natural navigation. In a store or office building, people and objects come and go through narrow pathways. Safe and appropriate unmanned operation under such conditions is one of the critical issues for practical application of service robots.

Company C, which produces innovative products for store shelf management, was developing an autonomous robot that can save the labor resources for shelf management. Company C planned to introduce the robots to a supermarket chain with approximately 3,000 stores nationwide in the United States.

Autonomous robots can perform monotonous and repetitive shelf management tasks on a predetermined schedule, resulting in less chances of a shortage of goods and allowing store staff to spend more time serving customers. This will improve store experience of customers and increase store sales. In addition, labor saving by autonomous robots can suppress rising personnel cost of stores. Company C expected their new autonomous robots would improve store and employee performance in terms of both revenue and expenditure.

On the other hand, Company C thought it necessary to develop an autonomous robot that would work in a store with adequate safety. Unlike warehouses with large floor areas, aisles in stores are narrow, and customers and shopping carts come and go irregularly in the aisles. The autonomous robots Company C was developing have a natural navigation to avoid making physical contact with customers, store staff or carts and harming a customer as a result.

While "autonomous movement" and "working in place of humans" are essential functions for an autonomous robot, Company C also focused on the safety measures to protect customers and store staff when they were developing the robot.

In particular, direct contact with customers, carts and any other objects in the aisles must be avoided.

Each of the wheels and components for drive and power supply for an autonomous robot is relatively large, and therefore the platform that houses all those parts tends to be large. Company C had to find a way to make the platform in a size small enough, both its width and depth, to navigate in narrow paths in stores.

Company C learned that assembling wheels, gears, and motors separately would increase the length from the motor shaft to the wheels and would not reduce the size of the platform that houses all of the motors, gears, and wheels. That size would prevent the autonomous robot from moving through the narrow aisles of the store, and would likely come into contact with people and objects in the aisles.

Company C considered to introduce an In-Wheel motor that houses a motor and gears to save space in the platform. However, they found that ready-made In-Wheel motors in the market were relatively wide and had problems in stopping accuracy. Company C was not able to find a company which could produce custom-made In-Wheel motors which they desired.

ASPINA had been supplying various types of motors to Company C for a long time. After hearing about the project, we decided to propose a new In-Wheel motor for the autonomous robot they were developing.

We specialize in the customization of drive systems including motors, and have provided many customers with custom products. For the project of Company C, we thought we would be able to develop an In-Wheel motor that meets their needs and work with them from designing principle prototypes through manufacturing of the final products.

The small size of the In-Wheel motors saved enough space to retract a large capacity battery between the wheels. Not only did it reduce the overall size of the platform, but it also lowered the position of the batteries toward the floor. This consequently lowered the robot's overall center of gravity and enhanced the stability of the robot. In addition, the high-precision gears provided the high stopping accuracy of the robot, thereby improving its safety.

The requirements of Company C were detailed and diverse beyond safety. We held regular meetings with Company C from time to time, understood the true meaning of their requirements and made various proposals. As a result, the In-Wheel motor acquired a high level of customer satisfaction.

Company C finished the autonomous robot with a sleek, uncluttered body that would not interfere with customers in the store aisles.

Company C wants to introduce their new store management system including the autonomous robots to supermarket chain stores nationwide. They believe the system will significantly change the store experience for customers and store operation including shelf management and employee management. They estimate that automating the repetitive simple shelf management tasks could save up to US $30,000 per store per year in man-hours, which could be spent on high value operations that contribute to revenue. In this way, stores with this system can improve the store's management metrics in terms of both revenue and expenditure.