IIT Jodhpur Researchers Design Robotic Trainers To Treat Lower Limb Disabilities

The robotic trainers have been designed in a way such that they provide a larger space to execute the required range of motion therapies. 

As part of the new study, researchers have proposed a robot manipulatory arrangement that is capable of providing motion to the ankle in all the three planes, namely sagittal, transverse and coronal. 

Source : ABP Live (with special arrangement with IIT Jodhpur)

Researchers at the Indian Institute of Technology Jodhpur have designed robotic trainers that can be used for physiotherapy applications to treat lower limb disabilities, a common problem in India. Lower limb disabilities are caused by age-related ailments, physical deformations, strokes, polio, and accidents, among others. The 2011 Census of India found that there are five million people with locomotor disabilities in India. 

People with these disabilities aim for lower limb rehabilitation, especially for gait recovery. However, rehabilitation is often time consuming and requires multiple physiotherapists. Of late, researchers have been assessing the benefits of robotic devices for lower limb rehabilitation. 

Robotic rehabilitation is beneficial because the therapist only needs to provide supervision and set up the device. IIT Jodhpur researchers recently designed robotic trainers that could perform lower limb rehabilitation in three different planes. 

The study describing the findings was published in the International Journal of Advanced Robotic Systems. 

Most existing robotic systems perform motions only in the sagittal plane, which is the imaginary plane that divides the body into the left and right parts. However, the sagittal movement is not sufficient for complete limb movement. 

How is the newly designed robotic system different from existing ones?

Therefore, robotic systems should ensure movements in transverse and coronal plans as well. The transverse plan refers to the upper and lower body, and the coronal plane refers to the front and back portions of the body. As part of the new study, researchers have proposed a robot manipulatory arrangement that is capable of providing motion to the ankle in all the three planes, namely sagittal, transverse and coronal. 

“The robotic trainer has a manipulator which can work in the x , y and z axes. Apart from that it has active ankle control. So overall 4-axis control,” Dr Jayant Kumar Mohanta, one of the authors on the paper, told ABP Live.

How does the robotic trainer work?

According to the study, the robotic trainer is a brace or wearable device like an exoskeleton that supports the leg, and is provided with a Cartesian or three-dimensional parallel manipulator to perform the required limb therapeutic motions in the transverse/horizontal and and sagittal/longitudinal planes. The robotic trainers have been designed in a way such that they provide a larger space to execute the required range of motion therapies. 

What movements does the new robotic trainer execute?

The researchers used computer-based simulations to check the effectiveness of the robotic trainer. They found that the design of the trainer allowed it to execute essential rehabilitation therapeutic movements like abduction, adduction, flexion and extension of the hip and knee joints. Abduction is the motion of a limb or appendage away from the midline of the body, adduction is the motion of a limb or appendage towards the midline of the body, and flexion refers to the bending movement of the body. 

In a statement released by IIT Jodhpur, the research lead said that the robotic trainer will help provide physiotherapy to paralytic patients, and to those who have lower limb disabilities due to injuries in the spinal cord. 

Also, the robot is safe, stable and robust during use because only linear actuators are used for the hip and knee movements. 

The newly designed stationary robotic trainer helps perform rehabilitation therapies for lower limbs at the knee and hip joints in sitting and lying positions, the study said. The robotic trainer can perform therapeutic motions for one leg at a time. 

The system can easily perform combined motions such as abduction, adduction, flexion, and extension of the hip and knee joints, and is capable of adapting in accordance to the features of the legs, the authors noted in the study.