Design & manufacturing a computerized Multi-Channel Isometric Dynamometer

In our technological world, there are plenty of opportunities to utilize science and engineering to improve exercise performances. Muscular strength is one of the main components of the physical fitness. In this regard, the Isometric Dynamometer is a scientific instrument intended to quantify the muscle strength. Hence, the aim of this project was to manufacture an innovative computerized isometric dynamometer package and relevant software. In the current project a high precision isometric force transducers (2000 and 5000 N), instrumental amplifier, high precision Analog-to-Digital Converter connected to a high speed microcontroller were implemented. A graphic LCD, MicroSD memory card used in the data logger to display and record the force data. Professional software was designed to communicate with the data logger by a USB port and display four-channel line charts in online mode. Offline data processing and record the processed data on a database is also available. This device provided an innovative method of simultaneous right & left side dynamometry using two sensors to measure any imbalance in the strength between two limbs. Additionally, this package has a grip dynamometer, a pull and press hands dynamometer, and optional connection to other force sensors. The linearity of the sensors’ output for 0, 10, 50, 100, 200 kg weights was 99.99 and test-retest measurements confirmed very high reliability (0.99±0.012). This package was extensively applied in the laboratory researches due to its unique simultaneous force measurement feature. Hence, this package with distinctive specifications can extensively implement in clinic, gym, laboratory, field tests.