# DEVELOPMENT OF cm-scale WALL CLIMBING HEXAPOD ROBOT WITH CLAWS

Save this PDF as:

Size: px
Start display at page:

## Transcription

2 Figure 2. Thrust mechanism which always pushes the claws during the swinging down phase Figure 3. Two-unit leg motion by a SMA and four bias springs the bias spring brings the legs back by naturally cooling the SMA spring. The thrust mechanism inclining 20deg in the direction of travel can always push the claws to the wall during the swinging down phase and raise the body during the swinging up phase. The movement of the COM perpendicular to the wall is 3mm (8.6% of the body height). Note that the CPU is PIC16F84A and controls the tripod gait by pulse width modulation (PWM). The walking cycle was set at 18.4s based mainly on the SMA spring response for cooling. 3. Surface roughness and absorption models 3.1 Surface roughness model and its definition In this section, we model the surface roughness of a concrete wall and analyze its relationship with the gripping force of the claw leg. First, to quantify the roughness, we fabricated a concrete wall model (stone powder clay consisting of La Doll PREMIX, PADICO). The wall was molded by disc paper to match the standardized roughness of the grain size established by Japan Industrial Standards (JIS). Figure 4 illustrates two types of surface models: (a) convex and (b) concave walls, and the claw condition. According to the pilot climbing experiments, it was difficult even for a beetle to climb on the convex type wall, because the condition in case (a) is not stable and caused its legs to slip. On the other hand, the condition in case (b) was relatively stable and the legs do not easily slip horizontally. In addition, the industrial concrete wall has many holes and is almost similar to the concave type. Thus, we focused on the concave type wall in this paper. Figure 5 shows the enlarged view of the concave type roughness of the fabricated wall and its mathematical model, which is defined as a hole of diameter d and offset h. Here, we consider the grain angle between the tangent of the hole and the line Figure 5. Mathematical model of the hole and an image of the fabricated concave type surface roughness of the wall perpendicular to the wall surface, θ, as the representative indexand discuss the climbing success rate. Table 1 shows the grain size used in the experiments, the JIS defined grain diameter, and the grain angle actually obtained. The values given in parentheses are the standard deviation. Since several grains combine in various holes, the standard deviation is large. Note that P12 means a grain size of No. 12 and an average grain angle of 17 deg. In other words, the greater the number, the smaller the hole diameter and the smoother the wall surface. The hole number and position are arranged randomly. P12 P14 P16 P24 P30 d [mm] Ϭ [deg] 17 (18) 25 (15) 32 (22) 36 (11) 41 (10) Table 1. Grain size and grain angle 3.2 Adsorption model analysis In this paper, we simplify the hexapod robot into a 2D model that treats the radial six legs as upper and lower legs, i.e., as two legs, and we calculate the equations of equilibrium for gripping the wall. Fig. 6 illustrates the relationship between the forces exerted when statically gripping the wall. Here, the arc of the holes is deformed as the tangent for simplification and θ is the grain angle defined in Section 3.1 (0 θ < π / 2). The equations of equilibrium for gripping are as follows: where F i is the reaction force from the wall (F i>0), W i is the friction between the claw and the wall surface, m is the mass of the robot, g is the constant of gravity, α is the leg arrangement angle (0 < α < π / 2), R is the length of the leg, and τ is the torque of the pinchforce. Additionally, i=1 means the upper leg and i=2 means the lower leg. The origin of the coordinates is the COM of the robot and the third equation is the moment around the COM. Simple geometry reveals that 0 < α + θ < π / 2. From these equations, we obtain (1) (2) Figure 4. Relationship between wall surface shape and claw position: (a) convex and (b) concave walls

3 From F 2 >0, the following condition is obtained, (3) (7) where τ /(Rmg) indicates the pinch force tobody weight ratio. Hence, the smaller the body, the larger this value is. Since muscle force and body weight are proportional to cross-sectional area and volume, respectively, this equation implies that smaller robots have an advantage. The slip conditions for the claws of the upper and lower legs are written as where µ is the coefficient of friction. The sign of the absolute value implies the direction of friction, i.e., the slip direction of the leg. From Eq. (2), W 1 is always positive. (4) Here, by letting W 2 =0, the following equation is obtained. This is the threshold for the slip direction for the lower leg. The first condition in Eq.(7) that the claw of the lower leg does not slip in the direction of the wall provides while the second condition in Eq.(7) that the claw of the lower leg does not slip in the inverse direction of the wall provides (8) (9) (10) However, the second condition in Eq.(10) is always neglected, because the condition in Eq. (6) is more restrictive. Additionally, the first condition is almost neglected because the condition μ > tan(α + θ) is rare. From the above discussion, the claw of the leg does not slip and the robot stays on the wall if and only if the conditions of Eqs. (6) and (10) hold. Figure 6. Simplified mathematical model for wall gripping Case A: The claw of the upper leg does not slip. From Eqs. (2) and (4), the condition that the claw of the upper leg does not slip is described as (5) 3.3 An example of the numerical analysis We introduce an example of the numerical analysis in this section. Figure 7 shows the areas expressed by the conditions in Eqs. (6) and (10), where the claw does not slip on the vertical wall. The parameters are as follows: μ=0.65 (obtained by the pilot experiment), m=13.5 [g], R=5 [cm], α=35 [deg], and g=9.8 [m/s 2 ]. The maximum pinch force to body weight ratio exerted by one leg is approximately 1.5, since the tension of the SMA spring is almost 0.02N. Since the robot uses every set of the three radial claw units for locomotion, the maximum pinch force to body weight ratio is approximately 3. This is extremely large compared with that of a human athlete. The gray area in Fig. 7(a) shows the condition that the claw of the upper leg does not slip. No any large pinch force stays the leg on the vertical wall in the condition of tanθ > μ. The gray area in Fig. 7(b) shows the condition that the claw of the lower leg does not slip. This area is divided into two regions based on the slip direction (that is, the thin dashed line, From the geometric condition of tan(α + θ) > tanθ 0 in Eqs. (3) and (5), the slip conditions for the upper leg are written as (6) Thus, the claw of the upper leg does not slip, if and only if Eq. (6) holds. Case B: The lower leg does not slip. From Eqs. (2) and (4), the condition that the claw of the lower leg does not slip is described as (a) The area where the claw of the upper leg does not slip DEVELOPMENTOFCM-SCALE WALL CLIMBING HEXAPOD ROBOTWITH CLAWS October /487

4 (b) The area where the claw of the lower leg does not slip Figure 7. An example of the non-slip area: α=35[deg] Eq. (8)). Too small pinch force below the thin dashed line makes the leg slip in the direction of the wall, while too large pinch force above the thin dashed line makes it slip in the inverse direction of the wall. Eventually, the gray area in Fig. 7(c) shows the condition that the robot can stay on the vertical wall. This area is restricted by the upper and lower slip conditions and the maximum pinch force to body weight ratio. We find that the maximum grain angle on which the robot can climb on the vertical wall is almost 30deg (grain size of P14). For the purpose of comparison, Fig. 8 shows the area that the robot can stay on the vertical wall in the case of α=20[deg]. We can see that the size of the gray area increases. According to the decrease of α, as the COM of the robot approaches the wall, the peeling moment decreases and the required pinch force becomes small. The minimum pinch force to body weight ratio required in the case of α=20[deg] also decreases compared with that in the case of α=35[deg]. Hence, the COM position is an important design consideration. Claw style vertical wall climbing is very difficult for m-scale robots, because the pinch force to body weight ratio is almost less than 1 which reduces the gray area. On the other hand, a cm-scale robot is not strongly affected by the pinch force; the friction coefficient with the wall is a more important factor. If the coefficient of friction becomes large, the chain dashed lines in Figs. 7 and 8 shift right and enlarge the gray area. Hence, miniaturization is an important design principle for a vertical wall climbing robot. (c) The area where the robot stays on the vertical wall P12 P14 P16 P24 P30 Climbing up OK OK NG NG NG Climbing down OK OK NG NG NG Horizontal travel OK OK NG NG NG Table 2. Experimental results for wall climbing and down and traveled horizontally on the vertical wall with a grain size of P12 and P14, i.e., a grain angle of 17deg and 25deg. The robot did not locomote on the vertical wall with a grain size of P16, P24, and P30, i.e., a grain angle of more than 30deg. This result is consistent with the numerical analysis in Section 3.3. Fig. 9 shows the stroboscopic pictures of the robot climbing on the vertical wall with the concave surface of P12 for 120s. The average velocities of climbing up, Figure 8. An example of the non-slip area: α=20 [deg] 4. Wallclimbing experiments Based on the above analysis, we performed horizontal and vertical movement experiments on the vertical stone powder clay wall with grain sizes of P12, P14, P16, P24, and P30. Table 2 shows the results. Here we define a case in which the robot locomoted for more than 60 seconds as OK and the others as NG. The robot climbed up Figure 9. Stroboscopic pictures during climbing on vertical wall with concave surface of P12

### Kungl Tekniska Högskolan

Centre for Autonomous Systems Kungl Tekniska Högskolan hic@kth.se March 22, 2006 Outline Wheel The overall system layout : those found in nature found in nature Difficult to imitate technically Technical

### Motion Control of a Bipedal Walking Robot

Motion Control of a Bipedal Walking Robot Lai Wei Ying, Tang Howe Hing, Mohamed bin Hussein Faculty of Mechanical Engineering Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor, Malaysia. Wylai2@live.my

### Supplementary Figure 1 An insect model based on Drosophila melanogaster. (a)

Supplementary Figure 1 An insect model based on Drosophila melanogaster. (a) Side and ventral images of adult female flies used to calculate the sizes of body and leg segments. Scale bar is 0.3 mm. Green,

### Spring Locomotion Concepts. Roland Siegwart, Margarita Chli, Martin Rufli. ASL Autonomous Systems Lab. Autonomous Mobile Robots

Spring 2016 Locomotion Concepts Locomotion Concepts 01.03.2016 1 Locomotion Concepts: Principles Found in Nature ASL Autonomous Systems Lab On ground Locomotion Concepts 01.03.2016 2 Locomotion Concepts

### Figure 1 Schematic of opposing air bearing concept

Theoretical Analysis of Opposing Air Bearing Concept This concept utilizes air bearings to constrain five degrees of freedom of the optic as shown in the figure below. Three pairs of inherently compensated

### Spider Robot for Motion with Quasistatic. Force Constraints

Spider Robot for Motion with Quasistatic Force Constraints Shraga Shoval, Elon Rimon and Amir Shapira Technion - Israel Institute of Technology - Haifa, Israel 32000. Abstract In quasistatic motions the

### Biped Walking Robot Control System Design

69 Biped Walking Robot Control System Design Jian Fang Abstract For biped walking robot posture instability problems presented this paper, ZMP gait planning algorithm and a time division multiplexing servo

### Stable Upright Walking and Running using a simple Pendulum based Control Scheme

1 Stable Upright Walking and Running using a simple Pendulum based Control Scheme H.-M. MAUS, J. RUMMEL and A. SEYFARTH Lauflabor Locomotion Laboratory, University of Jena, Germany E-mail: moritz.maus@uni-jena.de

### ZMP Trajectory Generation for Reduced Trunk Motions of Biped Robots

ZMP Trajectory Generation for Reduced Trunk Motions of Biped Robots Jong H. Park School of Mechanical Engineering Hanyang University Seoul, 33-79, Korea email:jong.park@ieee.org Yong K. Rhee School of

### Designing Diving Beetle Inspired Underwater Robot(D.BeeBot)

Designing Diving Beetle Inspired Underwater Robot(D.BeeBot) Hee Joong Kim Department of mechatronics engineering Chungnam National University Daejeon, Korea mainkhj@naver.com Jihong Lee Department of mechatronics

### Toward a Human-like Biped Robot with Compliant Legs

Book Title Book Editors IOS Press, 2003 1 Toward a Human-like Biped Robot with Compliant Legs Fumiya Iida a,b,1, Yohei Minekawa a Juergen Rummel a and Andre Seyfarth a a Locomotion Laboratory, University

### The Design and Performance of DASH

The Design and Performance of DASH Paul Birkmeyer Electrical Engineering and Computer Sciences University of California at Berkeley Technical Report No. UCB/EECS-2010-75 http://www.eecs.berkeley.edu/pubs/techrpts/2010/eecs-2010-75.html

### Numerical study on the wrist action during the golf downswing

Numerical study on the wrist action during the golf downswing C.C. Chen, Y. Inoue and K. Shibara Department of Intelligent Mechanical Systems Engineering, Kochi University of Technology, Kochi-prefecture,

### The Incremental Evolution of Gaits for Hexapod Robots

The Incremental Evolution of Gaits for Hexapod Robots Abstract Gait control programs for hexapod robots are learned by incremental evolution. The first increment is used to learn the activations required

### Evolving Gaits for the Lynxmotion Hexapod II Robot

Evolving Gaits for the Lynxmotion Hexapod II Robot DAVID TOTH Computer Science, Worcester Polytechnic Institute Worcester, MA 01609-2280, USA toth@cs.wpi.edu, http://www.cs.wpi.edu/~toth and GARY PARKER

### The Influence of Friction on Gait and Energy Efficiency of the Walking Robot Based on Rhythmic Control

The Influence of Friction on Gait and Energy Efficiency of the Walking Robot Based on Rhythmic Control H. Takemura, J. Ueda, Y. Matsumoto, T. Ogasawara Nara Institute of Science and Technology, Takayama-cho,

### Dynamic Lateral Stability for an Energy Efficient Gait

Dynamic Lateral Stability for an Energy Efficient Gait Zhenglong Sun a Nico Roos a a Department of Knowledge Engineering, Maastricht University P.O. Box 616, 6200 MD Maastricht, The Netherlands Abstract

### Variation in Pressure in Liquid-Filled Plastic Film Bags Subjected to Drop Impact

Materials Transactions, Vol. 53, No. 2 (12) pp. 291 to 295 Special Issue on APCNDT 9 12 The Japanese Society for Non-Destructive Inspection Variation in Pressure in Liquid-Filled Plastic Film Bags Subjected

### The Physics of Lateral Stability 1

The Physics of Lateral Stability 1 This analysis focuses on the basic physics of lateral stability. We ask Will a boat heeled over return to the vertical? If so, how long will it take? And what is the

### INCLINOMETER DEVICE FOR SHIP STABILITY EVALUATION

Proceedings of COBEM 2009 Copyright 2009 by ABCM 20th International Congress of Mechanical Engineering November 15-20, 2009, Gramado, RS, Brazil INCLINOMETER DEVICE FOR SHIP STABILITY EVALUATION Helena

### Contribution to the snow protection solutions for pitched roofs

Contribution to the snow protection solutions for pitched roofs Jozef Oláh1 and Michal Šida1,* 1 Slovak University of Technology in Bratislava, Faculty of Civil Engineering, Radlinského 11, 810 05 Bratislava,

### Simulation of the Hybtor Robot

Simulation of the Hybtor Robot Pekka Aarnio, Kari Koskinen and Sami Salmi Information and Computer Systems in Automation Helsinki University of Technology ABSTRACT A dynamic rigid body simulation model

### From Passive to Active Dynamic 3D Bipedal Walking - An Evolutionary Approach -

From Passive to Active Dynamic 3D Bipedal Walking - An Evolutionary Approach - Steffen Wischmann and Frank Pasemann Fraunhofer Institute for Autonomous Intelligent Systems (AiS) Schloss Birlinghoven, 53754

### Agood tennis player knows instinctively how hard to hit a ball and at what angle to get the ball over the. Ball Trajectories

42 Ball Trajectories Factors Influencing the Flight of the Ball Nathalie Tauziat, France By Rod Cross Introduction Agood tennis player knows instinctively how hard to hit a ball and at what angle to get

### OPTIMAL TRAJECTORY GENERATION OF COMPASS-GAIT BIPED BASED ON PASSIVE DYNAMIC WALKING

OPTIMAL TRAJECTORY GENERATION OF COMPASS-GAIT BIPED BASED ON PASSIVE DYNAMIC WALKING Minseung Kim Dept. of Computer Science Illinois Institute of Technology 3201 S. State St. Box 2082 Chicago IL 60616

### Toward a Human-like Biped Robot with Compliant Legs

Book Title Book Editors IOS Press, 23 1 Toward a Human-like Biped Robot with Compliant Legs Fumiya Iida a,b,1, Yohei Minekawa a Juergen Rummel a and Andre Seyfarth a a Locomotion Laboratory, University

### THEORY OF WINGS AND WIND TUNNEL TESTING OF A NACA 2415 AIRFOIL. By Mehrdad Ghods

THEORY OF WINGS AND WIND TUNNEL TESTING OF A NACA 2415 AIRFOIL By Mehrdad Ghods Technical Communication for Engineers The University of British Columbia July 23, 2001 ABSTRACT Theory of Wings and Wind

### Kinematic Differences between Set- and Jump-Shot Motions in Basketball

Proceedings Kinematic Differences between Set- and Jump-Shot Motions in Basketball Hiroki Okubo 1, * and Mont Hubbard 2 1 Department of Advanced Robotics, Chiba Institute of Technology, 2-17-1 Tsudanuma,

### DEVELOPMENT OF SAFE VERTICAL AXIS WIND TURBINE

The Seventh Asia-Pacific Conference on Wind Engineering, November 8-12, 29, Taipei, Taiwan DEVELOPMENT OF SAFE VERTICAL AXIS WIND TURBINE FOR OVER SPEED ROTATION Minoru Noda 1, Fumiaki Nagao 2 and Akira

### Simulation and mathematical modeling for racket position and attitude of table tennis

Acta Technica 62 No. 3A/2017, 135 142 c 2017 Institute of Thermomechanics CAS, v.v.i. Simulation and mathematical modeling for racket position and attitude of table tennis Jiansi Song 1 Abstract. Racket

### Faster and Smoother Walking of Humanoid HRP-2 with Passive Toe Joints *

Faster and Smoother Walking of Humanoid HRP-2 with Passive Toe Joints * Ramzi Sellaouti *1, Olivier Stasse *2, Shuuji Kajita *3, Kazuhito Yokoi *1 and Abderrahmane Kheddar *2 *1 JRL, AIST *2 JRL, CNRS

### Biomechanics of Parkour: The Vertical Wall-Run Technique

University of Colorado, Boulder CU Scholar Undergraduate Honors Theses Honors Program Spring 2015 Biomechanics of Parkour: The Vertical Wall-Run Technique Integrative Physiology, Peter.Lawson@Colorado.EDU

Available online at www.sciencedirect.com Procedia Engineering 3 () 94 99 5 th Asia-Pacific Congress on Sports Technology (APCST) Basketball free-throw rebound motions Hiroki Okubo a*, Mont Hubbard b a

### Concept of a Novel Four-wheel-type Mobile Robot for Rough Terrain, RT-Mover

The 2009 IEEE/RSJ International Conference on Intelligent Robots and Systems October 11-15, 2009 St. Louis, US Concept of a Novel Four-wheel-type Mobile Robot for Rough Terrain, RT-Mover Shuro Nakajima,

### Robot Walking with Genetic Algorithms

Robot Walking with Genetic Algorithms Bente Reichardt 14. December 2015 Bente Reichardt 1/52 Outline Introduction Genetic algorithms Quadruped Robot Hexapod Robot Biped Robot Evaluation Bente Reichardt

### BIOMECHANICAL MOVEMENT

SECTION PART 5 5 CHAPTER 12 13 CHAPTER 12: Biomechanical movement Practice questions - text book pages 169-172 1) For which of the following is the athlete s centre of mass most likely to lie outside of

### Exam 3 Phys Fall 2002 Version A. Name ID Section

Closed book exam - Calculators are allowed. Only the official formula sheet downloaded from the course web page can be used. You are allowed to write notes on the back of the formula sheet. Use the scantron

### Lab 7 Rotational Equilibrium - Torques

Lab 7 Rotational Equilibrium - Torques Objective: < To test the hypothesis that a body in rotational equilibrium is subject to a net zero torque and to determine the typical tension force that the biceps

### ScienceDirect. Rebounding strategies in basketball

Available online at www.sciencedirect.com ScienceDirect Procedia Engineering 72 ( 2014 ) 823 828 The 2014 conference of the International Sports Engineering Association Rebounding strategies in basketball

### AIRFOIL PROFILE OPTIMIZATION OF AN AIR SUCTION EQUIPMENT WITH AN AIR DUCT

THERMAL SCIENCE, Year 2015, Vol. 19, No. 4, pp. 1217-1222 1217 AIRFOIL PROFILE OPTIMIZATION OF AN AIR SUCTION EQUIPMENT WITH AN AIR DUCT by Li QIU a,b, Rui WANG a,*, Xiao-Dong CHEN b, and De-Peng WANG

### Chapter 13 Fluids. Copyright 2009 Pearson Education, Inc.

Chapter 13 Fluids Phases of Matter Density and Specific Gravity Pressure in Fluids Atmospheric Pressure and Gauge Pressure Pascal s Principle Units of Chapter 13 Measurement of Pressure; Gauges and the

### . In an elevator accelerating upward (A) both the elevator accelerating upward (B) the first is equations are valid

IIT JEE Achiever 2014 Ist Year Physics-2: Worksheet-1 Date: 2014-06-26 Hydrostatics 1. A liquid can easily change its shape but a solid cannot because (A) the density of a liquid is smaller than that of

### Objective: To launch a soda bottle rocket, achieve maximum time of flight, and safely land a payload (tennis ball).

Bottle Rocket Project 2016-17 Objective: To launch a soda bottle rocket, achieve maximum time of flight, and safely land a payload (tennis ball). Materials: 2 liter plastic soda bottle (carbonated beverage

### Planar motion hexapod walking machines: a new configuration

Planar motion hexapod walking machines: a new configuration G. Genta and N. Amati Politecnico di Torino, Dipartimento di Meccanica ABSTRACT The present paper develops a new configuration for walking machines

### 1. A tendency to roll or heel when turning (a known and typically constant disturbance) 2. Motion induced by surface waves of certain frequencies.

Department of Mechanical Engineering Massachusetts Institute of Technology 2.14 Analysis and Design of Feedback Control Systems Fall 2004 October 21, 2004 Case Study on Ship Roll Control Problem Statement:

### STUDIES ON THE OPTIMUM PERFORMANCE OF TAPERED VORTEX FLAPS

ICAS 2000 CONGRESS STUDIES ON THE OPTIMUM PERFORMANCE OF TAPERED VORTEX FLAPS Kenichi RINOIE Department of Aeronautics and Astronautics, University of Tokyo, Tokyo, 113-8656, JAPAN Keywords: vortex flap,

### Applying Hooke s Law to Multiple Bungee Cords. Introduction

Applying Hooke s Law to Multiple Bungee Cords Introduction Hooke s Law declares that the force exerted on a spring is proportional to the amount of stretch or compression on the spring, is always directed

### Velocity Based Stability Margins for Fast Bipedal Walking

Velocity Based Stability Margins for Fast Bipedal Walking Jerry E. Pratt 1 and Russ Tedrake 2 1 Florida Institute for Human and Machine Cognition jpratt@ihmc.us 2 Massachusettes Institute of Technology

### Clarification of Behavior of Huge Tsunami Action on Bridges - Hydraulic Model Experiment and Simulation Technology -

Clarification of Behavior of Huge Tsunami Action on Bridges - Hydraulic Model Experiment and Simulation Technology - 21 TOSHIMITSU SUZUKI *1 RIKUMA SHIJO *2 KAORU YOKOYAMA *3 SYUNICHI IKESUE *4 HIROFUMI

### DEVIL PHYSICS THE BADDEST CLASS ON CAMPUS AP PHYSICS

DEVIL PHYSICS THE BADDEST CLASS ON CAMPUS AP PHYSICS LSN 11-7: WAVE MOTION LSN 11-8: TYPES OF WAVES; LONGITUDINAL AND TRANSVERSE LSN 11-9: ENERGY TRANSPORTED BY WAVES Physics of Waves Questions From Reading

### Development of Biomimicry Wind Louver Surface Design

International Proceedings of Chemical, Biological and Environmental Engineering, V0l. 93 (2016) DOI: 10.7763/IPCBEE. 2016. V93. 6 Development of Biomimicry Wind Louver Surface Design Jaepil Choi 1, Donghwa

### and its weight (in newtons) when located on a planet with an acceleration of gravity equal to 4.0 ft/s 2.

1.26. A certain object weighs 300 N at the earth's surface. Determine the mass of the object (in kilograms) and its weight (in newtons) when located on a planet with an acceleration of gravity equal to

### Inertial compensation for belt acceleration in an instrumented treadmill

Inertial compensation for belt acceleration in an instrumented treadmill Sandra K. Hnat, Antonie J. van den Bogert Department of Mechanical Engineering, Cleveland State University Cleveland, OH 44115,

### Biomechanics Sample Problems

Biomechanics Sample Problems Forces 1) A 90 kg ice hockey player collides head on with an 80 kg ice hockey player. If the first person exerts a force of 450 N on the second player, how much force does

Parasite Drag by David F. Rogers http://www.nar-associates.com Copyright c 2005 David F. Rogers. All rights reserved. How many of you still have a Grimes rotating beacon on both the top and bottom of the

### Chain Drives. 1. As no slip takes place during chain drive, hence perfect velocity ratio is obtained

1. Introduction Chain Drives In Belt and Rope drives slipping may occur. In order to avoid slipping, steel chains are used. The chains are made up of a number of rigid links which are hinged together by

### Analysis of Shear Lag in Steel Angle Connectors

University of New Hampshire University of New Hampshire Scholars' Repository Honors Theses and Capstones Student Scholarship Spring 2013 Analysis of Shear Lag in Steel Angle Connectors Benjamin Sawyer

### Chain Drives. Chain Drives 759 C H A P T E R

Chain Drives 759 C H A P T E R 21 Chain Drives 1. Introduction. 2. Advantages and Disadvantages of Chain Drive over Belt or Rope Drive. 3. Terms Used in Chain Drive. 4. Relation Between Pitch and Pitch

### Effect of channel slope on flow characteristics of undular hydraulic jumps

River Basin Management III 33 Effect of channel slope on flow characteristics of undular hydraulic jumps H. Gotoh, Y. Yasuda & I. Ohtsu Department of Civil Engineering, College of Science and Technology,

### Heat Engine. Reading: Appropriate sections for first, second law of thermodynamics, and PV diagrams.

Heat Engine Equipment: Capstone, 2 large glass beakers (one for ice water, the other for boiling water), temperature sensor, pressure sensor, rotary motion sensor, meter stick, calipers, set of weights,

### Technical Note. Determining the surface tension of liquids by measurements on pendant drops

Technical Note Pendant Drop Measurements Technical note: TN316e Industry section: all Author: FT, TW Date: 12/2010 Method: Drop Shape Analyzer DSA100 Keywords: Methods, surface tension, interfacial tension,

### The effect of baseball seam height on the Magnus Force

The effect of baseball seam height on the Magnus Force Shawn Bowman Physics Department, The College of Wooster, Wooster, Ohio 44691, USA (Dated: May 7, 2014) Many people do not know that Major League and

### Section 1 Types of Waves. Distinguish between mechanical waves and electromagnetic waves.

Section 1 Types of Waves Objectives Recognize that waves transfer energy. Distinguish between mechanical waves and electromagnetic waves. Explain the relationship between particle vibration and wave motion.

### Engineering Flettner Rotors to Increase Propulsion

Engineering Flettner Rotors to Increase Propulsion Author: Chance D. Messer Mentor: Jeffery R. Wehr Date: April 11, 2016 Advanced STEM Research Laboratory, Odessa High School, 107 E 4 th Avenue, Odessa

### Research on Goods and the Ship Interaction Based on ADAMS

Research on Goods and the Ship Interaction Based on ADAMS Fangzhen Song, Yanshi He and Haining Liu School of Mechanical Engineering, University of Jinan, Jinan, 250022, China Abstract. The equivalent method

### 5. A bead slides on a curved wire, starting from rest at point A in the figure below. If the wire is frictionless, find each of the following.

Name: Work and Energy Problems Date: 1. A 2150 kg car moves down a level highway under the actions of two forces: a 1010 N forward force exerted on the drive wheels by the road and a 960 N resistive force.

### Abstract. 1 Introduction

Developments in modelling ship rudder-propeller interaction A.F. Molland & S.R. Turnock Department of Ship Science, University of Southampton, Highfield, Southampton, S017 IBJ, Hampshire, UK Abstract A

### AN ISOLATED SMALL WIND TURBINE EMULATOR

AN ISOLATED SMALL WIND TURBINE EMULATOR Md. Arifujjaman Graduate Student Seminar: Master of Engineering Faculty of Engineering and Applied Science Memorial University of Newfoundland St. John s, NL, Canada

### Activity P07: Acceleration of a Cart (Acceleration Sensor, Motion Sensor)

Activity P07: Acceleration of a Cart (Acceleration Sensor, Motion Sensor) Equipment Needed Qty Equipment Needed Qty Acceleration Sensor (CI-6558) 1 Dynamics Cart (inc. w/ Track) 1 Motion Sensor (CI-6742)

### How An Airplane Wing Creates Lift

2004 Transportation Education Academy Activity: How An Airplane Wing Creates Lift Standards being met for technological literacy: 1. Number 8 2. Number 9 3. Number 11 4. Number 18 Description: In this

### Chapter 11 Waves. Waves transport energy without transporting matter. The intensity is the average power per unit area. It is measured in W/m 2.

Chapter 11 Waves Energy can be transported by particles or waves A wave is characterized as some sort of disturbance that travels away from a source. The key difference between particles and waves is a

### Running with Flapping Wings

Running with Flapping Wings Kevin Peterson Ronald S. Fearing, Ed. Robert Full, Ed. Electrical Engineering and Computer Sciences University of California at Berkeley Technical Report No. UCB/EECS--76 http://www.eecs.berkeley.edu/pubs/techrpts//eecs--76.html

### Wind loads investigations of HAWT with wind tunnel tests and site measurements

loads investigations of HAWT with wind tunnel tests and site measurements Shigeto HIRAI, Senior Researcher, Nagasaki R&D Center, Technical Headquarters, MITSUBISHI HEAVY INDSUTRIES, LTD, Fukahori, Nagasaki,

### Activity Overview. Granny on the Ramp: Exploring Forces and Motion MO-BILITY. Activity 4B MS. Activity Objectives: Activity Description:

Granny on the Ramp: Exploring Forces and Motion Activity 4B MS Activity Objectives: Using ramps, spring scales and a Pom-Pom Granny model, students will be able to: Part 1: Make observations of physics

### DAMAGE TO OIL STORAGE TANKS DUE TO TSUNAMI OF THE MW OFF THE PACIFIC COAST OF TOHOKU, JAPAN

1NCEE Tenth U.S. National Conference on Earthquake Engineering Frontiers of Earthquake Engineering July 21-25, 214 Anchorage, Alaska DAMAGE TO OIL STORAGE TANKS DUE TO TSUNAMI OF THE MW9. 211 OFF THE PACIFIC

### PHYS 101 Previous Exam Problems

PHYS 101 Previous Exam Problems CHAPTER 14 Fluids Fluids at rest pressure vs. depth Pascal s principle Archimedes s principle Buoynat forces Fluids in motion: Continuity & Bernoulli equations 1. How deep

### Gait Evolution for a Hexapod Robot

Gait Evolution for a Hexapod Robot Karen Larochelle, Sarah Dashnaw, and Gary Parker Computer Science Connecticut College 270 Mohegan Avenue New London, CT 06320 @conncoll.edu Abstract

### Pendant Drop Measurements

KRÜSS pplication Note TN316d Page 1 Pendant Drop Measurements pplication note: TN316d Industry section: all uthor: Dr. Tobias Winkler Date: December 2010 Method: Drop Shape nalysis System DS100 Drop Shape

### Conventional Ship Testing

Conventional Ship Testing Experimental Methods in Marine Hydrodynamics Lecture in week 34 Chapter 6 in the lecture notes 1 Conventional Ship Testing - Topics: Resistance tests Propeller open water tests

### Comments on Homework. Class 4 - Pressure. Atmospheric Pressure. Gauge vs. Absolute Pressure. 2. Gauge vs. Absolute Pressure. 1.

Class 4 - Pressure 1. Definitions 2. Gauge Pressure 3. Pressure and Height of Liquid Column (Head) 4. Pressure Measurement and Manometers Please don t forget the special problem for the next HW assignment

### Kinematics-Projectiles

1. A volleyball hit into the air has an initial speed of 10 meters per second. Which vector best represents the angle above the horizontal that the ball should be hit to remain in the air for the greatest

### EVOLVING HEXAPOD GAITS USING A CYCLIC GENETIC ALGORITHM

Evolving Hexapod Gaits Using a Cyclic Genetic Algorithm Page 1 of 7 EVOLVING HEXAPOD GAITS USING A CYCLIC GENETIC ALGORITHM GARY B. PARKER, DAVID W. BRAUN, AND INGO CYLIAX Department of Computer Science

### Biologically-Inspired Locomotion of a 2g Hexapod Robot

Biologically-Inspired Locomotion of a 2g Hexapod Robot Andrew T. Baisch, Student Member, IEEE, Pratheev S. Sreetharan, and Robert J. Wood, Member, IEEE Abstract Here we present the design, modeling, and

### Gait-Based Compliant Control for Snake Robots

2 IEEE International Conference on Robotics and Automation (ICRA) Karlsruhe, Germany, May 6-, 2 Gait-Based Compliant Control for Snake Robots David Rollinson and Howie Choset Abstract We present a method

### Design Of Humanoid s Lower Limb Model

IBN 978-1-8466-xxx-x Proceedings of 011 International Conference on Optimization of the Robots and Manipulators (OPTIROB 011) inaia, Romania, 6-8 Mai, 011, pp. xxx-xxx Design Of Humanoid s Lower Limb Model

### Page 1

Contents: 1. Thrust and Pressure 2. Pressure in Fluids 3. Buoyancy 4. Why objects sink or Float when placed on surface of water? 5. Archimedes Principle 6. Relative Density Learning Objectives: The students

### Two dimensional kinematics. Projectile Motion

Two dimensional kinematics Projectile Motion 1. You throw a ball straight upwards with a velocity of 40m/s. How long before it returns to your hand? A. 2s B. 4s C. 6s D. 8s E. 10s 1.You throw a ball straight

### Chapter 11 Waves. Waves transport energy without transporting matter. The intensity is the average power per unit area. It is measured in W/m 2.

Energy can be transported by particles or waves: Chapter 11 Waves A wave is characterized as some sort of disturbance that travels away from a source. The key difference between particles and waves is

### Simulation-based design to reduce metabolic cost

Simulation-based design to reduce metabolic cost Overview: Lecture + Hands On Exercise 1. Generating and evaluating a muscledriven simulation of walking 2. Metabolics 101 3. Designing and evaluating devices

### A MODIFIED DYNAMIC MODEL OF THE HUMAN LOWER LIMB DURING COMPLETE GAIT CYCLE

Int. J. Mech. Eng. & Rob. Res. 2013 S M Nacy et al., 2013 Research Paper ISSN 2278 0149 www.ijmerr.com Vol. 2, No. 2, April 2013 2013 IJMERR. All Rights Reserved A MODIFIED DYNAMI MODEL OF THE HUMAN LOWER

### Projectile Motion Problems Worksheet

Projectile Motion Problems Worksheet For all questions, ignore the effects of air resistance unless otherwise stated. 1. One of the landing gears falls off a plane that is flying horizontally with a constant

Pressure Variation with Depth Pressure in a static fluid does not change in the horizontal direction as the horizontal forces balance each other out. However, pressure in a static fluid does change with

### Prototypical Robotic Fish with Swimming Locomotive Configuration in Fluid Environment

Prototypical Robotic Fish with Swimming Locomotive Configuration in Fluid Environment P.Nilas, N. Suwanchit, and R. Lumpuprakarn Abstract--Aquatic animal has always inspired many researchers interest to

### RELIABILITY ASSESSMENT, STATIC AND DYNAMIC RESPONSE OF TRANSMISSION LINE TOWER: A COMPARATIVE STUDY

RELIABILITY ASSESSMENT, STATIC AND DYNAMIC RESPONSE OF TRANSMISSION LINE TOWER: A COMPARATIVE STUDY Yusuf Mansur Hashim M. Tech (Structural Engineering) Student, Sharda University, Greater Noida, (India)

### l l k gnd Force Control for Spring-Mass Walking and Running leg gnd Devin Koepl, Kevin Kemper and Jonathan Hurst

Force Control for SpringMass Walking and Running Devin Koepl, Kevin Kemper and Jonathan Hurst Abstract We demonstrate in simulation that active force control applied to a passive springmass model for walking

### Generating Arachnid Robot Gaits with Cyclic Genetic Algorithms

Generating Arachnid Robot Gaits with Cyclic Genetic Algorithms Gary B. Parker Department of Computer Science Indiana University Bloomington, IN gaparker@cs.indiana.edu http://www.cs.indiana.edu/hyplan/gaparker.html

### RUNNING ON SOFT GROUND: SIMPLE, ENERGY-OPTIMAL DISTURBANCE REJECTION

CLAWAR 2012 Proceedings of the Fifteenth International Conference on Climbing and Walking Robots and the Support Technologies for Mobile Machines, Baltimore, MD, USA, 23 26 July 2012 543 RUNNING ON SOFT

### Analysis of stroke technique using acceleration sensor IC in freestyle swimming

Analysis of stroke technique using acceleration sensor IC in freestyle swimming Y. Ohgi, M. Yasumura Faculty of Environmental Information, Keio Univ., Japan H. Ichikawa Doctoral Prog. of Health and Sport