Anti-shaker Simulation for Arm Tremor Jakkrapun Chuanasa and Szathys Songschon + Department of Mechanical Engineering King Mongkut’s University of Technology Thonburi Bangkok, Thailand jakkrapun@hotmail.com, ithuchon@kmutt.ac.th Abstract. This paper presents a method for designing tremor suppression system that can reduce shaking in tremor. The design of the anti-shaker consists of a slider and a reciprocating device that counters the oscillatory movement. The oscillations according to tremor are considered as harmonic disturbances. With the use of LabVIEW and logical programming for PID controller, tremor suppression can be achieved efficiently. The results show that the amplitude, frequency, and weight which are the adjustable variables of the anti-shaker can be put to counter the shake symptom of tremor. Keywords: Tremor suppression, PID controller, Simulation, Reciprocating, Arm Tremor 1. Introduction Tremor is defined as the rhythmic, shaking movement and is observed at a relatively fixed frequency and amplitude [1], [4], [6], [10]. It is found that the tremor frequency range is between 4 to 12 Hz [3]. The causes of tremor include stress, anxiety, fatigue, alcohol, use certain drugs and other [9]. Physiological tremor is considered a ubiquitous property of the neuromuscular system that can be recorded from all limb segments under resting, postural or movement conditions [5]. There are two types of tremor always seen on the Parkinson's (PD) patients, resting and postural tremor. Resting tremor occurs when the muscles stay relax and limbs are fully supported. Postural tremor appears when a part of the body is maintained in a fixed position and may also persist during movement [2]. Resting tremor occurs on the range of 3-7 Hz, occurs in up to 75% of individuals with PD. Postural tremor is usually observed between 5 and 12 Hz and is symptomatic at around 60% of PD patients. Because the underlying Physiology of pathological tremor is not well understood, existing physical and drug therapies have not been successful in tremor treatment, giving rise to the need for alternative approaches to the problem of tremor suppression. Rui et al. [8] proposed an orthosis that can dynamically suppress pathological tremor, by applying viscous damping to the affected limb in a controlled manner. Recently, a wearable orthosis, which can adapted to each configuration of each joint of the upper limb has been proposed [7]. The orthosis can be used as a treatment for essential tremor patient. This paper proposes a general method for the design of tremor suppressing via reciprocating system using PID controller. The idea inspired by the work of [4] which proposed the analysis performed based on frequency and amplitude parameters. The fast Fourier transform(FFT) and higher-order spectra were used to extract frequency parameters. The discussion in this paper is limited to only simulation and programming. + Corresponding author. Tel.: +66(2)-470-9123 ; fax: +66(2)-470-9111. E-mail address: ithuchon@kmutt.ac.th 96 2011 International Conference on Circuits, System and Simulation IPCSIT vol.7 (2011) © (2011) IACSIT Press, Singapore