RSUSSH 2020
IN20-133 A Two-channel Electromyogram-based Robotic Arm System: A Continuously Wireless Control using Simulated Hand Gesture Patterns
Presenter: Mr.Thavatchai Chantarat
Rangsit University, Pathum Thani
Abstract
This research aims to conduct a simulation of the occurrence of electromyography signals in two groups of forearm muscles. Two switches were used to control the movement of the robotic arm continuously as to mimic hand gestures. This project is developed from a simple robotic arm with an ability of two movement directions for grasping restricted size and shape of object. The goal of this research is to enable the robot arm to pick up and hold various objects with different sizes, shapes and weights. The robot arm should be able to perform four hand gestures, including hand opening, object grabbing (using five and two fingers), and pointing with the index finger. The grasping pressure rate should be set automatically by wireless control to accommodate handling of objects with different levels of sensitivity. Test results demonstrate that the robotic arm can handle various shapes and sizes of objects and perform the four hand gestures with continuous control similar to human arm movement, with an accuracy of 93 %. This research can be used as a guideline for applying actual electromyography signals to control artificial arms for disabled people who we can return to live routinely with a quality of life.
Citation format:
Chantarat, T., Sangworasil, M., Angsuwatanakul, T., Puttasakul, T., O'Reilly, J., & Matsuura, T.. (2020). A Two-channel Electromyogram-based Robotic Arm System: A Continuously Wireless Control using Simulated Hand Gesture Patterns. Proceeding in RSU International Research Conference, May 1, 2020. Pathum Thani, Thailand.QUESTIONS & ANSWERS
Why did you invent the robot with only two input buttons? You can use more than two buttons and allocate one button for specific one gusture.
Would be possible to provide a force feedback when the robot grab an object?
How about the factor or algorithm which make it to be the smart hand like a real hand ot only off/on control?
Is there have biofeedback for calibrate force of grabbing?
The accuracy of this robotic arm is 93%, in your openion how to improve your system to increase the accuracy?
Anser for question of DR. SUEJIT PECHPRASARN
1.This research focuses on simulating a prototype system for use with people with disabilities. Most people with disabilities, all 8 of the forearm muscles are severely damaged, and only a few can be used. We designed the system as a 2-switch system to simulate the 2 muscles and assign the most necessary gestures.
2. This research consists of 5 force sensing resistor (FSR) feedback systems installed on the fingertips of the robot arm and in the palm. To show the effect of the pressure level while holding an object while doing the experiment.
The output voltage from the force sensing resistor circuit will change if there was pressure on the sensor. In other words, when there was no pressure on the sensor, the output voltage is equal to 0 volts. But if there was pressure applied to the sensor, the output voltage will increase according to the weight of the applied pressure, with the maximum value of 5 volts. the pressure could be specified in 3 levels, which are the lowest level, with a 0-300 grams force rate, an output voltage of 0-2.9 volts; moderate level, with a pressure rating of 301-600 grams, the output voltage was 2.9-3.5 volts and at the highest level, with a pressure rating of 601-1000 grams, the output voltage is 3.5-4.3 volts. It showed the pressure status with 3 color lamps, namely the lowest pressure level, displayed with green light bulbs. The medium pressure level was displayed with an orange lamp and the maximum pressure level was displayed with a red lamp with a robotic arm that stops immediately.
Thank you very much for your suggestion. We will use the haptic system to increase the efficiency of the prosthesis.
I must apologize for not mentioning the feedback control system in the video because of the limited time.
Answer for question of NUNTACHAI THONGPANCE
This robot arm is designed for continuous movement. It can be used to handle objects of many sizes and shapes, which is different from the open and close controls that can handle only one object. A robotic arm with open-close control, if wanting to handle objects of 9 different sizes and shapes,We may need to use up to 9 switches.
This research consists of 5 force sensing resistor (FSR) feedback systems installed on the fingertips of the robot arm and in the palm. To show the effect of the pressure level while holding an object while doing the experiment.
The output voltage from the force sensing resistor circuit will change if there was pressure on the sensor. In other words, when there was no pressure on the sensor, the output voltage is equal to 0 volts. But if there was pressure applied to the sensor, the output voltage will increase according to the weight of the applied pressure, with the maximum value of 5 volts. the pressure could be specified in 3 levels, which are the lowest level, with a 0-300 grams force rate, an output voltage of 0-2.9 volts; moderate level, with a pressure rating of 301-600 grams, the output voltage was 2.9-3.5 volts and at the highest level, with a pressure rating of 601-1000 grams, the output voltage is 3.5-4.3 volts. It showed the pressure status with 3 color lamps, namely the lowest pressure level, displayed with green light bulbs. The medium pressure level was displayed with an orange lamp and the maximum pressure level was displayed with a red lamp with a robotic arm that stops immediately.
I must apologize for not mentioning the feedback control system in the video because of the limited time.
Answer for question of JAROONRUT PRINYAKUPT
This research consists of 5 force sensing resistor (FSR) feedback systems installed on the fingertips of the robot arm and in the palm. To show the effect of the pressure level while holding an object while doing the experiment.
The output voltage from the force sensing resistor circuit will change if there was pressure on the sensor. In other words, when there was no pressure on the sensor, the output voltage is equal to 0 volts. But if there was pressure applied to the sensor, the output voltage will increase according to the weight of the applied pressure, with the maximum value of 5 volts. the pressure could be specified in 3 levels, which are the lowest level, with a 0-300 grams force rate, an output voltage of 0-2.9 volts; moderate level, with a pressure rating of 301-600 grams, the output voltage was 2.9-3.5 volts and at the highest level, with a pressure rating of 601-1000 grams, the output voltage is 3.5-4.3 volts. It showed the pressure status with 3 color lamps, namely the lowest pressure level, displayed with green light bulbs. The medium pressure level was displayed with an orange lamp and the maximum pressure level was displayed with a red lamp with a robotic arm that stops immediately.
I must apologize for not mentioning the feedback control system in the video because of the limited time.
Answer for question of ASSISTANT PROF. DR. SANI BOONYAGUL
The problem was that the surfaces of the forearm of the robotic arm were slippery, which made it difficult to pick up small objects. In my opinion, We have to improve the surface of the finger of the robotic arm with materials that have adhesion and elasticity, which allows small objects to be captured.
Thank you very much for your suggestion.
It is very impressive to see how the robotic arm can work but how can the patient carry the robotic arm if his weak forearm muscles ?