WEARABLE ROBOTSGROUP : 12

SUPERVISOR : MADAM SINNIRAName: 1) MUHAMMAD TAQRIZ SIRHAN BIN

ARIFIN 2)SYAMIM AMANI BIN AHMAD

FAUZI 3)ENGKU MOHD FIRDAUS BIN

ENGKU ALAM

Department of Mechatronics, Kulliyyah of Engineering

International Islamic University Malaysia (IIUM)Kuala Lumpur, MALAYSIA

GROUP : 12SUPERVISOR : MADAM SINNIRA

Name: 1) MUHAMMAD TAQRIZ SIRHAN BIN ARIFIN

2)SYAMIM AMANI BIN AHMAD FAUZI

3)ENGKU MOHD FIRDAUS BIN ENGKU ALAM

Department of Mechatronics, Kulliyyah of Engineering

International Islamic University Malaysia (IIUM)Kuala Lumpur, MALAYSIA

INTRODUCTIONS

What is wearable robots?• A wearable robot is a machine that facilitates

telepresence , a sophisticated form of interactive remote control. It allows a human operator to control a humanoid robot , also known as an android.

• The control unit consists of a suit that the operator wears

• Sights, sounds, and tactile effects sensed by the robot are imparted to the wearer by means of transducers

• Main objective in developing wearable robots is to assist or increase human’s ability (example strength).

APPLICATIONS OF WEARABLE ROBOT IN

MODERN LIFEA)Exoskeleton Bionic Suits

•It is a battery-powered, bionic device that is strapped over the user’s clothing. When equipped with the assistive device, walking can be achieved by a FORWARD LATERAL WEIGHT SHIFT TO INITIATE A STEP. BATTERY-POWERED MOTORS DRIVE THE LEGS AND REPLACE NEURO-MUSCULAR FUNCTION.

HOW IT WORKS?

MSS(muscular stiffness sensor) EMG(electromyogram) HAL( SEA(series elastic actuator)Compliant Actuator: AwAS(adjustable stiffness actuator) and EHA(electo-hydrostatic actuator)

Limitations and design issues• The early development of exoskeleton, the suit

can typically facilitate walking for individuals especially to those suffered from spinal cord injury

• Only provides functional based rehabilitation, gait training, and upright, weight bearing exercise under the supervision of a medical professional.

• Unable to follow the human motion instantaneously(must interpret first)

• Stiff joints hamper the transitions between the phase of motion

RoboWear (exeskeleton developed by NT,Research Inc) Upper limb – helps to uplifts heavy object(force multiplier) Lower limb can move, squat, stand up, conserve pose Lower limb has 4 DOF

How To Improvise Design Issue?

Use torsional springs which is the spiral springs instead of the helical spring .Why?

The spiral spring is used in the actuator system while the joint encoder and MSS are both use to measure n estimate the motion of the user precisely.

Why MSS is chose instead of EMG? Use MSS to measure the user’s fatigue The performance of these designs were being

tested through an experiment which is “standing-up and squatting with and without exoskeleton”

1. Torque is generated when the motor wind/unwind the spiral springs.

2. Generated torque transmits to the pelvis and knee joints of the exoskeleton

3. Encoder and MSS measure the user motions.QuestionBriefly explain the mechanism when the user in

squatting motion and standing up motion.If the user is in stationary but feels fatigue, do

the motor will stop and causing the spiral spring to unwind?

Experiments of Squatting and Standing Up wearing RoboWear

What are the mechanism involve?

RoboWear’s working principle is govern by the measurement of the muscles stiffness which is detected by the MSS(muscles stiffness sensor)

Encoders is used to detect the motion of the robot once the user move thus initiate the robot to propel forward.

How can we activate the robot even when the user does not move considering that her fatigue starts to accumulate?

Solutions• EMG(electromyogram) can be use and it is the most

popular choice to measure muscle activity.• However MSS(muscle stiffness sensor) is the most

recommended due to reasons of less cost and more convenient for the user.

• The positions of MSS(muscle stiffness sensor) on the thigh muscles are represented by the blue dots in the figure

Which muscle is the most suitable to be used as indicator to determine the

user’s fatigueness level?Biceps fermoris – activated when a

human enduring heavy loadsThose muscles which indicated by the

blue dots activated when a human squats

These muscles also generate torque for maintaining position and lifting the body

Therefore the sensor information from the biceps fermoris can be a good indicator to mark the fatigueness level

Introduction• The main causes of physical disabilities in hands

are C5 and C6 spinal cord injuries(SCIs) and stroke.

• These patients have good movement from shoulder to wrist, but no hand movement at all.

• Due to nearby fingers, having robot joints on the side of the fingers are not possible.

• To resolve this problem, many robots decided to put joints and link frames on the backside of the hand.

• Due to these transmission links at the back of the hand, robots get bulky and hard to wear.

• Instead of joint and linkage actuation mechanism, joint-less robots with pneumatic actuation mechanism and tendon drive mechanism have been developed.

• Now we have new problem that is size.• These pneumatic system needs more

space and not compact with the size of the hand.

• Joint-less robotic hand with tendon drive mechanism is one solution.

• To have actuation in this mechanism, wire has to be fastened in both distal and proximal part of the joint(to control wire length)

• To fulfill the compactness criteria of the wearable robotic hand, SNU Exo-Glove with glove and joint-less tendon drive mechanism has been developed.

SNU Exo-Glove

• Still, we got problem on fingertip force and fingertip direction.

• Then, due to flexibility of glove, actuating wire causes deformation of glove and rigid models become impracticable.

solution

• To overcome these problems, improving the non linearity of the SNU Exo-Glove is the best solution.

• The model has been built to estimate the actuated wire length with wire tension for certain metacarpophalangeal(MCP) joint angle in flexion.

• Plus, tendon anchoring(TA support) is mention to increasing the fingertips transmission force and reducing the nonlinearity.

SNU Exo-Glove’s problems

• First is the finger attachment point movement due to the compliance of the skin.

• Second is palm Velcro strap movement due to the deformation of the glove.

• Third is TA Support movement due to the skin compliance.

• The last is wire elongation.

Assumption to this model

Several assumption has to be made for modelling. That is :•First, friction is negligible.•Second, TA Support can move only in one direction.•Third, Velcro straps are assumed to be point.

• Experiment has been conducted to see the relationship between the wire tension and actuated wire length for fixed MCP angle.

• To maintain constant MCP angle while actuating index finger, palm has been fixed to test bed.

• While experiment was running, wire tension and actuated wire length was recorded by LabVIEW and two camcorders placed in two different angles were recording the movement of nonlinear factors of the robot for motion tracking.

Result of the experiment

legends• Blue : actual actuated wire length from test• Red : total estimated wired length from model • Black : TA Support movement • cyan : wire attachment point movement • magenta : wire path change by palm pulley movement (taken from motion

tracking) • Green : wire elongation(calculated by wire tensile

test results)• Red : sum of four different nonlinearity

factors,black, cyan, green and magenta.

• By the fact that red dots are following blue dots well, we presume that modeling fits the actual system well.

• Result in figure 2 shows that the red dots, estimation by using MCP joint flexion model, tends to follow blue dots, actual result from the test, well.

• This result verifies the feasibility of the model and this model will be expended to PIP and DIP joint in future to complete finger flexion model in tendon driven wearable robotic hand.

HYBRID ASSISTIVE LIMB(HAL) ROBOT

• a type of wearable robot that is designed to assist the movement of those patients who have physical disability

• an exoskeleton robot• for those who suffered from hemiplegia

WHAT IS HEMIPLEGIA?• a type of paralysis that occurs at the arm, leg, and torso on the same side of the body caused

by the damage at certain part of the brain or might be resulted from illness, injury or stroke

LOWER LIMB PART OF HAL

• power unit• main controller• setup unit• sensors

HAL CONTROL DESIGN • CYBERNIC VOLUNTARY

CONTROL• CYBERNIC AUTONOMOUS

CONTROL-using phase sequence method

PHASE SEQUENCE METHOD

Divided into 3 stages:

Conclusions • Basically, these advancements of the technology in

the wearable robots/exoskeleton field have been booming in the past 5years.

• These exoskeleton have the potential to be life-altering.

• We once looked at these as being the future, except now it turns out that the future is approaching much more rapidly that than we had expected.

• Within the next 5-10 years we could possibly see these exoskeletons out on the battlefield helping ,as well as, protecting our soldiers.

• Further down the road we could also see robotic sugeons in operating rooms being controlled by surgeons in another room.

• But most likely, even sooner than both of those options, is the potential to see these exoskeletons helping the disabled as well as people with degenerative deseases.

• The potential for this technology seems endless and the effects it will have on the human race will be monumental.