This project is about analyzing the human brain system and using brain waves extensively by performing some real-time activities implementing on the robotic hand model in order to address the common social issues such as medical and health care applications. Today, millions of peoples are suffering due to the lack of a functional arm preventing from doing things. In Sri Lanka there are about over thousands of people are suffering from disabilities. Sri Lanka Ministry of Health state that the number of disabled persons in Sri Lanka will be increased by 24.2% by 2025. Most of them will suffer from hand disabilities. Disabling a hand costs huge disadvantages to a human being. Living without a hand will be a major problem for those who having hand disabilities. The aim of this project is to give a solution to those who suffer from hand disabilities and make their life efficient and easy.
The field of robotics is growing fast in order to make people’s life efficient and easy. There are various machines or robots designed are manufactured in this particular field to help handicapped people facing the problems like blindness, broken legs or arms, body part dislocation, etc. But design a robot for medicine is not that easy. There are some limitations in robotic works. One of the most important factors of robotic use in medicine is accuracy. Especially, the biomedical robotic designs are required very high accuracy when they taking the decisions. The biosignal-based controlling system is the next step in order to achieve more accuracy. Bio-signals are referring as the Electroencephalography (EEG), Electromyogram (EMG) and Electrocardiogram (ECG), etc. The robot hand motions and movements of the fingers will be completely dependent on the brainwaves which human beings produced. This project mainly focused on Electroencephalography (EEG) signals also known as the brain waves. However, according to concepts related to bio-medicine and engineering, we will hope to design and develop a three-finger robotics arm that will be controlled by the human brain. This robotic hand will be designed to pick and hold objects using the mind and also more useful for people who having hand disabilities.
Problem statement
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Millions of people suffer from disabilities and reside in countries all over the world. The majority of them have problems with their arms, hands, and legs.
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According to the Ministry of Health's annual report, the overall number of disabled persons in Sri Lanka is expected to rise by 24.2 percent by 2025. A large number of people will suffer from hand disabilities as a result.
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Table 1 depicts the results of the 2012 Census of Population and Housing (Sri Lanka). According to the data, Sri Lanka has a significant number of persons with hand disabilities.
Table 1
The Census of Population and Housing Data of Sri Lanka (2012).
Major District in Sri Lanka | Type of Disability (%) |
Seeing | Hearing/Speaking | Hand | Legs |
Colombo | 26.8 | 28.7 | 21.7 | 41.0 |
Gampaha | 34.0 | 38.0 | 25.2 | 48.3 |
Kaluthara | 44.2 | 47.5 | 30.8 | 58.5 |
Kandy | 35.7 | 42.4 | 25.9 | 49.4 |
Kurunegala | 45.0 | 49.2 | 32.8 | 63.5 |
Anuradhpura | 52.3 | 49.9 | 33.6 | 67.1 |
Even now, these percentages are getting increasing. The disabling hand is costs huge disadvantages to a human being. Living without a hand is a major problem for those who have hand disabilities. This project gives a solution to those who suffer from the hand disabilities and make their life efficient and easy.
Anatomy of the Human Hand
The bones of the human hand (Fig. 1) and wrist give support and flexibility to the body, allowing it to move things in a variety of ways. Each hand has 27 different bones, which give it an amazing range of motion and accuracy. The thumb, index, middle, ring, and little fingers are the five fingers of a human hand. The fingers move in two main ways:
We can flex our fingers to grab and hold onto objects and extend our fingers to reach out for things. Usually, each finger joint can be controlled individually and the human hand can bend the distal joint (at the fingertip) and the proximal joint (in the middle of the finger) separately. When all the finger flexor muscles and tendons pull together, humans make a tight fist.
Human fingers are compromising with 3 main joints,
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DIP – Distal Inter Phalange
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PIP – Proximal Inter Phalange
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MCP – Metacarpus Phalange
These joints have different relative motion angles (as shown in Table 2).
Table 2
Finger Motion Angle of MCP, PIP, DIP.
Finger Joint | Motion angle / degree (◦) |
MCP | 0 < θ < 100 |
PIP | 0 < θ < 105 |
DIP | 0 < θ < 85 |
EEG Lead Systems
The internationally standardized 10–20 system is usually employed to record the spontaneous EEG. In this system 21 electrodes are located on the surface of the scalp, as shown in Fig. 2, A and B. Reference points are Nasion, which is the delve at the top of the nose, level with the eyes; and Inion, which is the bony lump at the base of the skull on the midline at the back of the head. From these points, the skull perimeters are measured in the transverse and median planes. Electrode locations are determined by dividing these perimeters into 10% and 20% intervals. Three other electrodes are placed on each side equidistant from the neighboring points, as shown in Fig. 2B. In addition to the 21 electrodes of the international 10–20 system, intermediate 10% electrode positions are also used. The locations and nomenclature of these electrodes are standardized by the American Electroencephalographic Society. In this recommendation, four electrodes have different names compared to the 10–20 system; these are T7, T8, P7, and P8.
Bipolar or unipolar electrodes can be used in EEG measurement. In the first method, the potential difference between a pair of electrodes were measured. In the latter method, the potential of each electrode is compared either to a neutral electrode or to the average of all electrodes.