Hydraulic Modular Articulated Robot – Preliminary Design
ME481 Group 3Abed Alnaif
4A Mechatronics EngineeringUniversity of Waterloo
October 6, 2008
Hydraulic Modular Articulated Robot
Introduction
Articulated robot is a series of links connected by rotary joints
Hydraulic Modular Articulated Robot
Needs Assessment / Problem Formulation
Articulated robot that is modular and extendable Modules are identical Length of robot is easily customized by
adding or subtracting modules Modules need to be able to support rest
of the robot
Hydraulic Modular Articulated Robot
Problem Definition
Goals: Have 2-module prototype built Have control algorithm developed
Objectives: Accuracy of control Compact size
Hydraulic Modular Articulated Robot
Constraints & Criteria
Constraints: $1500/module Capable of lifting 60 kg with 2 modules Capable of supporting at least 10 modules
Criteria: Size Load Capabilities Controllability (ease and accuracy of
control)
Hydraulic Modular Articulated Robot
Current Technologies & Patents
Current modular robots are built from electrical actuators Low power-to-weight ratio
Hydraulic Modular Articulated Robot
Current Technologies & Patents (2)
Modular, reconfigurable robots
Hydraulic Modular Articulated Robot
Current Technologies & Patents (3)
Snake-arm robot
Hydraulic Modular Articulated Robot
Current Technologies & Patents (4)
Patent 6323615, titled “Modular Articulated Robot Structure” Vague Published 02/03/2004
Hydraulic Modular Articulated Robot
Advantages of Hydraulics
Helac Hydraulic Helical Rotary Actuator
Weight = 6 kg
Nominal output torque = 190 N-m
100 mm
140 mm
Amtec Servo Motor and Gear Box
Weight = 3.2 kg
Nominal output torque = 45 N-m
180 mm
90 mm
High Power Density
Hydraulic Modular Articulated Robot
Advantages of Hydraulics (2)
Micromatic Vane Hydraulic Rotary Actuator
Weight = 9.75 kg
Nominal output torque = 773 N-m
124 mm
195 mm
High Power Density
Hydraulic Modular Articulated Robot
Advantages of Hydraulics (3)
Easily customizable mechanical advantage Force = Pressure * Area Velocity = Flow / Area
Ease and accuracy of control Ability to lock position of modules
Hydraulic Modular Articulated Robot
Disadvantages of Hydraulics
Need to use valves Oil leaks Noisy
Hydraulic Modular Articulated Robot
Conceptual Designs
2 Rotary Actuators
Hydraulic Modular Articulated Robot
Conceptual Designs (2)
2 Rotary Actuators Reconfigurable
Hydraulic Modular Articulated Robot
Conceptual Designs (3)
3 Cylinders Can rotate, as well as extend the
next module
Hydraulic Modular Articulated Robot
Challenges
Achieving compactness Routing of hydraulic hoses Controls
Nonlinear Effects of positioning one module on
other modules (Action / Reaction Forces) Funding
Hydraulic Modular Articulated Robot
Questions?
Questions?