ProFoot is an indigenously developed, high-performance prosthetic foot. ProFoot is our effort to provide a better alternative to the suboptimal or very expensive products in the market currently, and our goal is to provide users with a highly functional, affordable product. Anyone who has undergone foot amputation requires a prosthetic foot to get rehabilitated and participate in the community. We have developed a framework for foot design using Finite Element Analysis and will implement that for an actual design using innovative geometries and materials. Multiple concept designs are currently being developed, and their performance is theoretically evaluated across various parameters. The innovative designs incorporate magnesium alloy as the choice of material and are of unique geometries, the combination of which presents significant advantages.
The conventional method of controlling a wheelchair is using a joystick. Some impairments include cerebral palsy (CP), muscular dystrophy, high levels of spinal cord injury, etc., where people may not have the fine motor control required to operate a joystick. In the case of children with CP, providing means of independent mobility contributes to numerous areas of cognitive and sensory development that are otherwise denied. In this work, an alternate mechanism has been designed for wheelchair operation, which detects gross body motion to control the wheelchair.
The Body-Motion wheelchair can be controlled by the motion of any body part, like the head/trunk/hand/leg, etc. When the user moves his/her body forward/sideways, the wheelchair goes in the forward/sideways direction. This method of control also provides therapeutic benefits to the user. The flexibility of the control mechanism allows it to be customised to the user's abilities so that users can use whatever body part movement they can control in the wheelchair.
A pediatric version of the chair that is close to a product version of the concept has been developed. The device has undergone field testing at Vidya Sagar: about 10 children with CP (at Gross Motor Function Classification System (GMFCS) levels of 4 and 5) were trained to control the wheelchair.
Features of the device:
Flexible control mechanism - can use a wide variety of motions as inputs
Sensitive - can be tuned so that fine motions can be detected
Easy Calibration feature
Dual sensors to sense the user's intended direction of motion
Use of a variable neutral CG point for calibration
Therapeutic tool - the movement of the chair provides a reward mechanism for posture training and control
The same concept can be used on mobility devices for users with CP, Quadriplegia, etc.
Vivek Sarda worked on this device as part of his DD project (2013-14). A provisional patent application has been filed for this device. The Innovative Student Projects (ISP) scheme of IIT Madras, an alumni initiative, funded this project. We are working on further product development for eventual commercialisation.
Swimming Pool Lift
People with locomotor impairments do not have any means for full-body exercise while constrained to a wheelchair. Swimming gives them an opportunity for exercise and an immense sense of freedom since the water supports their body weight. To make swimming pools accessible to the physically challenged, assistive devices are required, and a swimming pool lift serves the purpose. The figure shows the sequence of operation of the lift. The motorized prototype designed by student Swostik Sourav Dash (DD, 2013) was demonstrated at the Velachery SDAT Aquatic Complex in July 2013. A new prototype that is manually operated has been designed and was put to use extensively during the State Level Paralympic Swimming Championships held at Velachery SDAT Aquatic Complex in July 2015.
Power Assist for a Wheelchair
The most extensively used wheelchair in India is a manually driven wheelchair. A manual wheelchair requires the user to have considerable upper limb strength to propel the wheelchair. The required effort is multiplied when the user needs to move on uneven terrain or travel long distances. One solution is a motorized wheelchair, but the cost of a motorized wheelchair ranges from INR 65,000/- to a whopping INR 3.7 lakhs, depending on the functionality of the wheelchair. Thus, one of the prime constraints is the cost of a motorized wheelchair. In addition to this, existing motorized wheelchairs pose several challenges to users, including portability and weight (powered wheelchairs weigh more than 45kgs). A common drawback in powered wheelchairs is the lack of modularity; they cannot be easily folded or disassembled. This makes it difficult to transport the wheelchair when not being used. Most powered wheelchairs cannot be easily used when not powered. This prevents the usage of the wheelchair in manual mode, which could be a major problem in case of a power failure. These were the motivating reasons for the project. The power assist we have developed for manual wheelchairs addresses these issues. The first design was developed by Sripriya Kalidoss, SD Karthikeyan and Vivek Sarda.
EZ-LOK: lever-operated knee for Knee-Ankle-Foot Orthosis (KAFO)
Most KAFOs available in India have knee joints with drop-locks - two for each braced limb. The user has to bend down to lift the locks to enable the knee to bend for sitting down. This is difficult and can be embarrassing in crowded places such as buses. Bilateral users find it especially difficult to operate the drop locks on both limbs simultaneously to sit down. In addition, when a KAFO user stands up, the drop locks can sometimes get stuck and not lock automatically, leading to instability and safety concerns. Current designs of these orthotic knees also have protruding parts that tear clothes. Imported drop lock alternatives are expensive, mostly available only in urban areas and require frequent maintenance. Our simple lever-operated joint (EZ-LOK) design solves all these problems. Users operate a single lever unobtrusively located at the hip to unlock the joint. The lock clicks into place when the user stands up. The design has been developed by Ganesh Bapat (PhD scholar) with support from Muthuvishvashwaran, Mohan Varma and Seethapathi. The Indian Patent Office has granted a Design Patent for this design (No.290752).
All-terrain Wheelchair: Optimus
Optimus is a manual lever-operated wheelchair for use outdoors in rough terrain. The design uses locally available bicycle parts and is easily repairable and affordable. The mechanism to attach and detach the lever is easy, so the user can easily switch the chair to push rim mode. The elongated base frame ensures stability on rough terrain. The user can quickly stop the chair with brakes on the pushing levers. The wheelchair has a small turning radius, making it easily manoeuvrable in tight spaces. The wheelchair is also foldable, making it easy to transport. The design was developed by Saish Kapadi (B.Tech 2014) with support from Rajesh and Sandilya Bharathi.
AREBO (Arm Rehabilitation Robot) is a 6-degree-of-freedom robot for training individual joint movements at the shoulder and elbow. This robot is under collaboration with Prof. Sivakumar Balasubramanian and his team at the Bioengineering department, Christian Medical College, Vellore.