An electric scooter (a device having various commercial names) is a light vehicle for the handicapped and for others who are limited in the use of their feet, such as the elderly.
The painful subject of the quality of life of the handicapped is often raised at The Zomet Institute, especially before the holidays. People with restricted mobility are comfortable on weekdays by virtue of such equipment as an electric wheelchair for the handicapped controlled by a joystick, or with an electric scooter. But on Shabbat these unfortunate people lose their ability to move around. Are they destined to "remain in one place" on Shabbat, without any way to go to a synagogue or meet friends and relatives?
Not only does the halacha take the needs of these people into consideration, it in fact obligates them to enjoy the Shabbat. In response to this need, The Zomet Institute has developed a complex halachic-technical solution that enables them to move around on Shabbat without becoming a burden on others. The Shabbat system has been approved and is recommended for use by prominent rabbis, even for rides that do not involve a mortal threat. For more than ten years, adult men and women have moved around on Shabbat in strict accordance with the halacha, taking advantage of this innovative technology. The halachic principles involved are gramma (indirect operation) and "continuous change of current." These principles have been implemented in different ways in hundreds of subject areas and on thousands of individual devices. Similarly to an electric wheelchair, the main switch of the scooter is turned on using the principle of gramma. This is also used to change direction from forwards to reverse. Once the motor has been turned on, it remains in a state of a continuous "crawl." All the rider does is change the level of the current, an action which is permitted on Shabbat under these circumstances.
It is recommended that anybody who needs a Shabbat system should consult with a rabbi who knows him personally before installing it.
One point that is often raised is the question of the appearance of sin. But this concept is relative and changes as public awareness increases. Publicizing halachic solutions (such as on this website) and putting a prominent sign on the equipment is the proper response to this dilemma. We take this opportunity to turn to the sextons of the synagogues, in the name of the organization "Maagalei Tzedek," to take care of the needs of the handicapped by providing easy access, proper rest rooms, etc.
Important note: Not all scooters on the market can be outfitted with the Zomet Institute mechanism. It is recommended to consult with the engineers in The Zomet Institute before buying a specific model of scooter.
Can the Shabbat scooter be used outside of an eruv? This is indeed a problem. There are rabbis that permited this and the main reason given is that the scooter for the disabled can be considered like a garment, shoe or accessory belonging to a person's body. For more details you can read the letter correspondence (Hebrew) between several rabbis on this issue. It's advised to consult with the local rabbi about this issue.
The Zomet Institute does not sell scooters but only installs the Shabbat systems. Some companies sell electric scooters with the Zomet Institute system already installed, such as Afikim Electric Vehicles,(+972) -4-6754825 in Israel, and Amigo, in the United States.