984 IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT, VOL. 52, NO. 3, JUNE 2003 Data Glove With a Force Sensor Kostas N. Tarchanidis, Member, IEEE, and John N. Lygouras, Member, IEEE Abstract—This paper presents a data glove equipped with a force sensor. The construction and the electronic circuit are also described. The glove is selected to be a rubber-coated cotton glove. The sensors are firmly attached to the rubber-coated glove using cyanoacrilic glue. The force sensor is made of a steel plate substrate where the commercial strain gauges are attached. The plate is at- tached on the thumb. The strain gauge bridge is powered by a dig- ital current source. A digital sine is produced by a microcontroller and a DAC with current output. At the peak, the microcontroller produces a digital output signal. This signal triggers the data ac- quisition system. The force sensor presents a linear response and a resolution of 0.38 N with a sensitivity of 0.05 V/N. The combination can be used in robotics, telecheric applications, biomechanics and virtual reality applications. Index Terms—Current source, data glove, digital sine, direct dig- ital synthesis, embedded application, flexsensor, force sensor, mi- crocontroller, strain gauge. I. INTRODUCTION D ATA gloves are widely used in many applications, including virtual reality applications, robotics, telecheric applications, and biomechanics. This paper introduces a new data glove that will have not only the information of finger position, but the force the fingers apply on an object, as well. The force sensor presented here is categorized as tactile. Tac- tile sensing is defined as the continuous sensing of variable con- tact forces. There are many applications for sensors that can ac- curately measure finger and hand forces [1]. Different types of transducers have been proposed to be used as force sensors. They have been proposed using piezoresis- tive, piezoelectric, capacitive, optical, ultrasonic, and conduc- tive polymer principles. Most of the force sensors are attached straight to the finger, either with glue or adhesive tape. Reston and Kolesar [2] described a robotic tactile sensor fab- ricated from piezoelectric polyvinilidene fluoride film (PVDF). It is, however, a poor choice for a finger-mounted tactile sensor due to its limited load range and inability to measure static forces. Beede et al. [3] developed a silicon-based force sensor pack- aged in a flexible package and described its performance with human subjects. The sensor was only demonstrated under labo- ratory conditions. Manuscript received May 29, 2001; revised November 19, 2002. K. N. Tarchanidis is with the Department of Petroleum Technology, Kavala Institute of Technology and Education, Kavala, TK 6540, Greece (e-mail: ktarch@teikav.edu.gr). J. N. Lygouras is with the Department of Electrical and Computer En- gineering, Democritus University of Thrace, Xanthi, TK, Greece (e-mail: ilygour@demokritos.cc.duth.gr). Digital Object Identifier 10.1109/TIM.2003.809484 Fig. 1. Data glove with force sensor pressing a rubber ball. Da Silva et al. [4] developed a tactile force sensor where the strain gauges are placed in a hard aluminum case. This sensor has to be attached with adhesive tape on the finger. There are few commercially available tactile sensors, and the most appropriate to be used in applications similar to the project presented in this paper are FlexiForce by Tekscan [5] and the C2000 by PPS [6]. Although these solutions have quite good characteristics, it was most difficult to acquire them. Further- more, this project has the principle of customized solutions. In this paper, a cotton-made glove coated with rubber (dipped in latex) is used as the substrate to host the finger position sen- sors (flexsensors) and the strain gauge force sensor. II. DATA GLOVE SENSORS The sensors that are selected to be attached to the glove are the flexsensors, made with the same principle as the strain gauges (changing their resistance on the bending occasion), but they have large resistance differences. They present 13-K resis- tance on zero degrees bending, and 35-K on 90 . This pro- duces less noise when the signal is fed into the data acquisition system. Cyanoacrilic glue is selected as the adhesive material, and the sensors are firmly attached to the rubber glove. Many materials are used for the glove, including leather, cotton, and plastic. The latex dipped cotton gloves proved to be ideal for this application, since the sensor is attached firmly and the glove can easily be removed without destroying the sensors. The data glove is shown in Fig. 1. The circuit diagram for the flexsensor is presented in Fig. 2. The AD voltage is equal to v R R V R R V 0018-9456/03$17.00 © 2003 IEEE