As global populations age, there’s increasing need for technologies that can help people who have suffered paralysis caused by stroke. Later this year, Toyota will commercialize the Welwalk WW-1000 rehabilitation assist robotic system centering on a leg brace that helps patients get back on their feet and walking again.
Toyota’s Welwalk WW-1000 consists of a linked treadmill, touch-panel control screen, overhead harness, video monitor and the motorized brace. Feedback is an essential feature: along with the visual feedback from cameras in front and on the side, voice and sound feedback can tell the patient whether the load on the frozen leg is too big or too small.
The Japanese government approved the Welwalk WW-1000 as a certified medical device in November 2016. Toyota plans to rent 100 units to medical centers beginning in September. There will be a set up cost of 1 million yen ($9,173) and a monthly fee of 350,000 yen ($3,210).
Stroke is one of the leading causes of paralysis. Patients who are trying to retrain their motor muscles can use long leg braces to support their weight, but it’s still difficult to swing the frozen leg forward to walk; using smaller braces carries the risk of the knee buckling.
How Toyota’s Welwalk WW-1000 Robotic System Works
When patients are standing and using the Welwalk WW-1000, the knee motor ups the torque to keep the leg stable. When walking, data from a pressure sensor in the sole of the brace is used to analyze leg movement and accurately flex the knee at the right moment. While the system is quite bulky, with the brace weighing 6 kg and the treadmill measuring 2.7 meters long and weighing 800 kg, Toyota said experienced therapists can get patients ready to use it in as little as one minute.
Toyota Welwalk WW-1000 (Credit: Toyota)
“With this, the patient can walk long distances at gaits that approximate natural walking,” Akifumi Tamaoki, general manager of Toyota’s Partner Robot Division, said at a press event at company headquarters in Tokyo. “One of the outstanding features of the Welwalk is that it combines the best of the short and long braces.”
Ten years in the making, the Welwalk was developed with Fujita Health University Hospital and trialed at 23 hospitals with over 300 patients since 2014. Eiichi Saito, a doctor and executive vice president at Fujita Health University Hospital, showed a video of a 60-year-old stroke patient who doubled her walking speed on the Welwalk in four weeks.
“With a training robot, patients can start walking quite effectively,” Saito says. “Therefore, I believe this technology has great potential.”
Toyota Welwalk WW-1000 Robotic Leg (Credit: Toyota)
Toyota imagines a variety of its Partner Robots working alongside people in everything from child-rearing and education to agriculture, forestry and mining. It began developing robots to assist automobile manufacturing in the 1980s. In 2004, it unveiled a humanoid Partner Robot that can play the trumpet, and in 2011 introduced nursing and healthcare robotic technologies. Its Segway-like Winglet, also being trialed in Japan, is one example of how Toyota envisions seniors getting around with sensor-equipped mobile platforms.
In nursing homes and facilities for handicapped people, Toyota has also been experimenting with machines it calls HSR, or human support robot, that can help mobility-challenged users by fetching or picking up objects from the floor.
“In 2050, the number of workers supporting one elderly citizen will be reduced to one-third of what it was in 2000, which means the burden on the working generation to care for the elderly will be tripled,” says Toshiyuki Isobe, manager at Toyota’s Frontier Research Center. “We want to realize by 2050 a society where partner robots can support the lives of senior citizens and help with their nursing care.”