Teodor Akinfiev

Climbing cleaning robot for vertical surfaces

Purpose – The purpose of this paper is to develop a climbing cleaning robot with reasonably high productivities for vertical surfaces.Design/methodology/approach – The paper analyzes the reasons for the low productivities or unreliable work of cleaning robots for vertical surfaces. Based on this analysis, a design of a new robot is created. Pilot studies were performed of laboratory and industrial prototypes of a new robot.Findings – The paper shows that the new design provides a reliable and high‐performance work of the cleaning robot for vertical surfaces. Thus, the new design provides increasing in productivities more than ten times compared with the known robot.Research limitations/implications – In this paper, it is assumed that the speed of the robot during the process of surface cleaning is constant. For future research the algorithm is proposed that automatically maintains such speed of the robot, which depends on the degree of dirtiness and is optimal for the surface to be cleaned.Practical impli...

A Device for Automatically Measuring and Supervising the Critical Care Patient’S Urine Output

Critical care units are equipped with commercial monitoring devices capable of sensing patients’ physiological parameters and supervising the achievement of the established therapeutic goals. This avoids human errors in this task and considerably decreases the workload of the healthcare staff. However, at present there still is a very relevant physiological parameter that is measured and supervised manually by the critical care units’ healthcare staff: urine output. This paper presents a patent-pending device capable of automatically recording and supervising the urine output of a critical care patient. A high precision scale is used to measure the weight of a commercial urine meter. On the scale’s pan there is a support frame made up of Bosch profiles that isolates the scale from force transmission from the patient’s bed, and guarantees that the urine flows properly through the urine meter input tube. The scale’s readings are sent to a PC via Bluetooth where an application supervises the achievement of the therapeutic goals. The device is currently undergoing tests at a research unit associated with the University Hospital of Getafe in Spain.

The Influence of Gravity on Trajectory Planning for Climbing Robots with Non-Rigid Legs

In this paper questions related to the occurrence of departures of a legged climbing robot from the given trajectory are considered. The basic idea of the paper is to show that, if there are slackness and non-rigidities, the legged climbing robot moving upon an inclined or vertical plane, departs systematically from the planned trajectory. It is demonstrated that these departures result from the gravity and are of systematic character. It is also shown how the inclusion of torsion effect changes substantially the nature of systematic errors arising from robots movement along the inclined surface.

Nondestructive testing of the state of a ship’s hull with an underwater robot

The possibility of nondestructive testing of a ship’s hull with the AURORA underwater robot is discussed. The robot performs underwater cleaning of a ship’s hull with simultaneous contactless measuring of the thickness of the hull sheet with an ultrasonic detector; it tests the state of the protective coating and restores the shape of the underwater part of the hull.

A low cost device for monitoring the urine output of critical care patients.

In critical care units most of the patients’ physiological parameters are sensed by commercial monitoring devices. These devices can also supervise whether the values of the parameters lie within a pre-established range set by the clinician. The automation of the sensing and supervision tasks has discharged the healthcare staff of a considerable workload and avoids human errors, which are common in repetitive and monotonous tasks. Urine output is very likely the most relevant physiological parameter that has yet to be sensed or supervised automatically. This paper presents a low cost patent-pending device capable of sensing and supervising urine output. The device uses reed switches activated by a magnetic float in order to measure the amount of urine collected in two containers which are arranged in cascade. When either of the containers fills, it is emptied automatically using a siphon mechanism and urine begins to collect again. An electronic unit sends the state of the reed switches via Bluetooth to a PC that calculates the urine output from this information and supervises the achievement of therapeutic goals.

Robust Cascade Controller for Nonlinearly Actuated Biped Robots: Experimental Evaluation

In this paper we consider the postural stability problem for nonlinearly actuated quasi-static biped robots, both with respect to the joint angular positions and also with reference to the gripping effect between the foot/feet against the ground during robot locomotion. Zero moment point based mathematical models are developed to establish a relationship between the robot state variables and the stability margin of the foot (feet) contact surface and the supporting ground. Then, in correspondence with the developed dynamical model and its associated uncertainty, and in the presence of non-modeled robot mechanical structure vibration modes, we propose a robust control architecture that uses two cascade regulators. The overall robust control system consists of a nonlinear robust variable structure controller in an inner feedback loop for joint trajectory tracking, and an H∞ linear robust regulator in an outer, direct zero moment point feedback loop to ensure the foot-ground contact stability. The effectiveness of this cascade controller is evaluated using a simplified prototype of a nonlinearly actuated biped robot in double support placed on top of a one-degree-of-freedom mobile platform and subjected to external disturbances. The achieved experimental results have revealed that the simplified prototype is successfully stabilized.

Nontraditional Drives for Walking Robots

The results of a series of researches on the new nontraditional drives are presented. These drives with changing transmission ratio and dual properties have been developed for walking machines, whose working elements make movements with stop and stoppage. Analytical calculations, simulations and experiments with prototypes confirmed a high effectiveness of the designed drives.

Concerning a Technique for Increasing Stability of Climbing Robots

Legged-climbing robot is considered. Each foot of the robot has an electromagnet system for robots holding on a metal surface. This surface can be both vertical and inclined, including negative slope. Analytical calculation of robot stability under turn over or sliding conditions has been made. Critical slopes have been determined. One of these slopes corresponds to minimal reserve of robot stability towards sliding and another to minimal reserve of robot stability towards turning-over. As total reserve of stability of a robot is always equal to the minimal one of these reserves. Additional support elements of elastic material with high coefficient of friction, along with electromagnet, allows to increase minimal reserve of robot stability towards sliding. The use of such support elements leads to redistributing force of normal support reaction between electromagnet (which surface has low coefficient of friction) and additional support element (which surface has high coefficient of friction). It is just what leads to increasing the total friction force and as a consequence to increasing of minimal reserve of robot stability towards sliding.

A device for automatic measurement of the critical, care patient's urine output

This paper presents a patent-pending device capable of recording and supervising the urine output of a critical care patient. The device is based on a high precision scale that measures the weight of a commercial urine meter. To isolate the device from the patients movements, and to guarantee that the urine flows properly through the various tubes of the urine meter, we have designed a support frame made up of Bosch profiles. The scales readings are captured by an electronic unit and sent to a PC via Bluetooth. A Java application running on the PC records them and supervises the therapeutic goals that the healthcare staff has established for the urine output, and warns of any deviation from these goals. This device does not break the sterility of the commercial urine meter and is easy to build with readily available components. Therefore, this solution is ideal to conduct a series of clinical studies based on a more continuous and accurate monitoring of urine output throughout the stay of a patient in a critical care unit.

Height Control of a Resonance Hopping Robot

This paper presents a model-based height controller for a one-legged resonance hopping robot. The particular construction of the robot with compensation of energy losses during robot’s flight, and the use of a special dual drive with changeable transmission ratio for allowing an additional decrease of energy expenses, impose some specific requirements on the height controller. Equations of motion in vertical dimension are derived and solved to produce the actuator command that allows the robot to regulate its apex height. The reference control signals are obtained using minimum time and minimum energy as optimization criteria. Some experiments, carried out with a prototype of the resonance hopping robot, are also reported to prove the effectiveness of the proposed controller.