Making a Stand


Polio is something that time has seemingly forgotten. It’s hard to believe it took the mobility and lives of so many millions or that a president was left in a wheelchair for life. But one man’s reoccurrence of this disease recently led to another man’s opportunity.

“It relapsed in 2000 so essentially he was dependent,” says Anurag Purwar, a research associate professor in the school of mechanical engineering at Stony Brook University. “Getting to a walker from the seated position was the challenge. In 2007, he called me.”

Professor Anurag Purwar and his invention. Image: Daniel Brennan, Stony Brook University

That call from a retired doctor, Hari Pillai, began a journey that still continues, as Purwar develops a device that helps people achieve the self-sufficiency so many of us take for granted.

“He said he saw I was in mechanical robotics and maybe could I help him with this,” Purwar recalls. “There are devices but they didn’t fulfill what he needs. It couldn’t be like what was used in an institutional facility—needing a hoist and a pulley. It would need to both independently assist him in getting up and be used as a walker.”

The design approach began with writing a statement of what the device was supposed to do, then researching the market and coming up with the conceptual design. On two sides of the walker there would be two sets of paddle mechanisms and a six-part linkage system along with a wire harness and remote control ability to lift the user. It wouldn’t be done in an up-and-down fashion because it needed to go with the motion of the shoulder joint, along with following the path of the hip, one that resembles an “S.”

Professor Purwar's device helps disabled people rise to the standing position in order to walk. Image: Stony Brook University

Two functioning prototypes were created, one weighing 25 pounds and the other 30 pounds. The latter was finally chosen because the other required the person to lean forward and that would disqualify many from utilizing it. It is primarily aluminum, Purwar adds.

Even though the machine was created with Dr. Pillai in mind, it turns out it actually may work best for a medical facility. Maneuverability can be difficult in the rooms of many private residences because it can be hard for the machine to cut a path. Medical facilities also stand to benefit from improved health for their caregivers. With this profession having one of the highest rates of injuries from trying to move patients, the machine could be vital to their career longevity and quality of life in retirement.

But those other positive effects won’t allow Purwar to be sidetracked from helping those who wish to live on their own. Pillai’s initial request has turned into a friendship and Purwar still hopes to present his friend with the alternative he needs. Working on a third prototype, he realizes this may be a work in progress for many more years to come but he’s up to the challenge.

“I have derived a lot of satisfaction from being able to apply systems to people’s lives,” he says. “In academia, we write research papers, we present at conferences, but I’ve appreciated this chance to work on important practical problems like this.”

Eric Butterman is an independent writer.

In academia, we write research papers, we present at conferences, but I’ve appreciated this chance to work on important practical problems like this.

Prof. Anurag Purwar, Stony Brook University


September 2013

by Eric Butterman,