These exoskeleton boots can make you walk faster than ever
Stanford University / Kurt Hickman
A team of engineers at Stanford University has created a unique pair of boots that can make you walk faster by putting in less energy and effort. These special exoskeleton boots are constructed using a carbon fiber frame, a motor, and a pair of shoes. The boots could assist leg movement in individuals going through leg injuries or mobility impairment issues.
The motor winds a cable that flexes the foot, providing assistance when the person pushes off the ground during walking. There are several assistive devices with similar designs, but what sets this device apart is the maximum assistance it offers.
Moreover, the boots are also capable of providing personalized assistance to each user. Patrick Slade, the first author of the study and postdoctoral scholar at Stanford, told IE, "One breakthrough in our work was developing a machine-learning model that used portable sensor data from the exoskeleton to determine what the best assistance pattern was when using our device."
He further added, "this is incredibly important because everyone walks differently and requires different assistance patterns to receive the maximum benefits."
The exoskeleton boots can help you walk better
The researchers suggest that until now, the use of most exoskeleton devices was limited to lab settings, and none of them has shown real-world benefits of reducing the energy it takes to walk or increasing walking speed. This is because our highly evolved and specialized muscle, tendon, and skeletal design already provide us with very efficient movement. So, in reality, it's actually very difficult to help humans walk.
However, the newly developed ankle exoskeleton has been able to demonstrate improved walking performance for humans in real-world conditions. The design is powerful enough to perform 50% to 75% of the effort that the human calf typically provides during walking. In addition, the engineers also equipped the device with portable sensors for personalized assistance to find the best assistance pattern for each individual.
The sensors monitor factors like ankle angle, ankle velocity, and assistance torque of the exoskeleton while a user walks. Then by using machine learning, the model processes this data to further understand the pattern that best suits the walking style of a user, and finally, it adjusts the device settings accordingly.
This is how the battery-powered ankle boots enable a person to use less muscle effort, which results in energy savings and increases walking speed. During outdoor testing, where participants walked at varying speeds while starting and stopping walking bouts, the boots provided benefits equivalent to removing a 30 lbs (13.8 kg) backpack.
Moreover, it increased the walking speed of users by 9% compared to normal shoes. "Our device was designed through rigorous lab testing and can provide approximately three times as much assistance (ankle torque) compared to previous devices, which is necessary to provide the largest benefits to the user in terms of reducing energy during walking and increasing walking speed," said Slade.
Limitations and potential of the ankle exoskeleton
According to Slade and his team, the data-driven model of the boots can improve human-robot collaboration across a wide array of tasks (factory work, assisted living, surgery, etc.), and therefore, the device has the potential to optimize robotic responses to human movements. Another obvious use is that it can make people with temporary or permanent mobility impairment issues more independent.
The assistive device could even turn walking into a less demanding physical activity for elderly people. However, the findings of the current study are based on tests that were conducted on healthy subjects. This means that further research is required to confirm the benefits the exoskeleton can provide to humans.
"For this study, we had young and healthy subjects wear the device to evaluate the benefits. This is typical for safety in evaluating a device before working with a clinical population. We are now starting to study how these devices can impact mobility for people with mobility challenges, such as the elderly or muscular diseases," Slade told IE.
The study is published in the journal Nature.