BCI Based Control of Lower Limb Exoskeleton

Project Title

BCI Based Control of Lower Limb Exoskeleton

Project Area of Specialization Biomedical EngineeringProject Summary

Exoskeletons are becoming famous day by day. As the population of the world keeps on increasing so does a lot of problems increase in life. Some of these problems are the increase in health issue, accidents which cause disability to many people like it becomes difficult for such person to stand and walk due to which their life changes completely and they depend on others for every small thing which increases frustration on both the sides. So, to overcome this problem the world is now moving to Brain Machine Interface (BCI). Our project lower limb exoskeleton  is also based on brain computer interfacing (BCI) technology. Our target is to capture/use the brain signals from the muscles and then use them to generate desired commands. These muscle signals are in the form of voltage difference whenever the muscle makes any movement, these signals (voltage difference) are detected by the specific muscel sensors and then after processing of the signals desired commands are generated at the output. So in short we can define our problem statement is :

“To develop a BCI based control of lower limb exoskeleton which will assist elderly people to stand and walk.”

Project Objectives

Objectives of our project are:

1. To develop the EMG based control of lower limb exoskeleton.
2. To generate commands by intension detection.

Developing a Control system involves the Signal acquisition – signal processing – generation of signal commands. Signal acquisition is done by EMG sensors (EMG muscle sensor).

Project Implementation Method

Implentation of project is based on four steps  or can be called as four techniques which are given below:

Signal Acquistion:

Signal acquistion is done by EMG muscles sensors. In this brain signals are extracted from muscles of thigh. From thigh muscles signal acquistion is done for hip joint and from calf muscles signal acquistion is done for knee joint. 4 sensors are used signal acquiston. 2 on each thigh muscles and 2 on calf muscles.

Signal Processing:

In this feature extraction is done on the raw signal that were achieved form signal acquition process.

Decoding/Encoding:

In this machine learning algorithm is applied on the data obtained after the feature extraction. LDA (Linear Discriminant Analysis) algorithm is applied to achieve the acceptable accuracy and desired pattern of the brain signals so that specific commands can be generated according to need.

Feedback:

As from Newton’s law we know “To every action there is always an adequate reaction.” In the end feedback of the system is taken, mainly the feedback is in the form of visulization that whether the desired action is performed or a complete gait cycle is executed or not.

Benefits of the Project

Exoskeletos are becoming famous day by day. There are different types of exoskeletons like some are used for power augmentation, some are used for rehabilitation purposes. Our project (exoskeleton) falls in the category of exoskeltons which are used for rehabilitation purposes.

1. Our project is used to assist the elderly people to help them in stand and walk also it provides them an external support.
2. In our project signal acquistion is done by EMG muscle sensors which is a complete non invasive technique to acquire the brain signals from the muscles so it doesnot harm human body. 
3. Our project can be used for rehabilitation purposes in medical field also.
4. This project provides new path in engineering and neurorobitics field in Pakistan.

Technical Details of Final Deliverable

Final deliverables of the project are:

1. Data will be recorded by using EMG muscle sensors.
2. Exoskeleton has 2 DOF. (hip and knee joint).
3. Commands are dependent on gate phases.
4. Acceptable accuracy will be met by signal.

Final Deliverable of the Project HW/SW integrated systemCore Industry HealthOther Industries Medical Core Technology RoboticsOther Technologies NeuroTechSustainable Development Goals Good Health and Well-Being for People, Industry, Innovation and InfrastructureRequired Resources

Item Name	Type	No. of Units	Per Unit Cost (in Rs)	Total (in Rs)
			Total in (Rs)	80000
EMG Muscle sensors	Equipment	5	12000	60000
PCB Fabricated	Equipment	1	5000	5000
ESP32 devkit V1	Equipment	2	1300	2600
Lithium cells battery	Equipment	1	2400	2400
Report Printings	Miscellaneous	3	2000	6000
overheads	Miscellaneous	1	4000	4000