Hydrabot The Modular Electro-Hydraulic Robot Arm University of Waterloo Under the supervision of: Dr. Relevant Links . Contact Information. Acknowledgements. University of Waterloo Jump to: Project Description. Co-op. Results. Sponsors. Jan Paul Huissoon Deputy Chair of the Department of Mechanical & Mechatronics Engineering. Documents.By: Abed Alnaif 4B Honors Mechatronics Engineering. such as a camera or gripper. An end-effector.Project Description A robot arm. which would make it unsuitable for most applications of modular robot arms. Modular robot arms are kinematic chains consisting of identical modules which can be easily assembled or disassembled. Currently. These robots are shown in Figure 2 below. the actuators being the muscles. Image obtained from Wikipedia. Schunk. in space) to have a human arm. Figure 1 An industrial robot arm. In Schunk’s robots. such as when the robot arm is expected to reach around an object or manoeuvre itself into a confined space such as a pipe. Modular. is mounted onto the end of the arm.g. and these are powered either electrically. Schunk also offers modular and reconfigurable robots. pneumatically. is a series of links whereby each link is capable of moving in relation to other links.g. meaning that the user also has flexibility in the orientation of each module. and the sensors being the proprioceptive feedback. Most modular robot arms are also reconfigurable. such as in industrial automation and in places where it is too dangerous (e. Actuators are the devices responsible for moving the links. in a radioactive environment) or impractical (e. . A modular robot arm that is not reconfigurable would be restricted to movement in a single plane. Robot arms may be thought of as being similar to human arms: the links being the bones. the modules are not the same size (e. the end-effector being the hand. This gives the user the ability to change the shape of the arm and the workspace (or reach) of the end-effector. Robot arms have found numerous applications. This gives the user control of the number of degrees of freedom (or the number of joints) in the arm by simply adding or subtracting modules. Amtec offers its “PowerCube” line of modules for modular and reconfigurable robots. there are three suppliers for such robots: Amtec. Sensors are used to provide information on the position and movement of the robot arm. These modules consist of two cubes. as shown in Figure 1 below. the lower modules are larger than the upper ones). and this is the device responsible for interacting with the environment. reconfigurable robots have found applications wherever a robot arm with many degrees of freedom is needed. which are capable of continuous curvature. or small compartment. Their robots work by attaching three cables to the top of each module and adjusting the tension in the cables in order to position the modules.g. hydraulically. OC Robotics is the only commercial supplier of snake-arm robots. one cube being a servo motor while the other being a gearbox. and OC Robotics. duct. 2MB). Rotation of the torque arm causes rotation of the next module (or link) in the robot arm. Figure 3 below shows the 3D model of the design. Since both cylinders are connected to the torque arm. The design uses two Parker hydraulic cylinders that act on a torque arm. all commercially-available modular robots use electrical actuators. Position feedback of the modules is obtained by rotary potentiometers. since hydraulic actuators have higher power-to-weight ratios than electrical actuators.pdf. A Parker proportional valve is chosen for this task. . This project attempts to increase the payload and to increase the number of modules which can be supported in a modular and reconfigurable robot arm by using hydraulic actuators. Snake-arm robot offered by OC Robotics (bottom). their motion is dependent on each other and only one valve is needed to control both cylinders. As shown in Figure 2 above.Figure 2 Modular. A prototype consisting of two modules will be fabricated. reconfigurable robots offered by Amtec (top left) and Schunk (top right). A more detailed description of the design can be found in the design report (. the robot was completely assembled and connected to a hydraulic powerpack. The cylinders are colored yellow and the valve blue. and results. Since then.pdf. 2009. testing. The robot performed very well at the symposium on March 23. and accurate movements. as well as the engineering drawings of the prototype can be found in the final report (. 3D model without the cylindrical housing (middle). the robot has been running very well. smooth. 2.8 MB). producing fast. Results On March 18. Figure 4 3D model of design shown with the cylindrical housing (left). and without the cylindrical housing (right).Figure 3 3D model of design shown with the cylindrical housing (left).000 movements. and photograph of the actual module (right). In the 3D model. More detailed information regarding the fabrication. It made a very impressive exhibit as it ran nonstop through the entire symposium. A video of the robot is shown below: . completing nearly 2. the cylinders are colored yellow and the valve blue. Figure 4 below shows the robot’s response to a 45° step command. com. Robert Wagner for manufacturing the base (manifold) plates and the top plate. Acknowledgements I would like to thank Professor Jan P. Parker Hannifin Corporation – designer and manufacturer of motion control products 2.ppt. 2008 Contact Information Please feel free to email me at [email protected]. and so many of my classmates who have given me valuable technical and non-technical advice. Huissoon for his valuable advice regarding the overall design. Videos of OC Robotics snake-arm robot 7. as well as power transmission components and accessories for hydraulic power units 3. Final Design Presentation (. Jim Johnson and Terry Seip for helping me with the plumbing. and from the Department of Mechanical & Mechatronics Engineering (who provided space. Department of Mechanical & Mechatronics Engineering at the University of Waterloo 4. 2009 2. and covered the remaining costs). 0. MP Filtri – designer and manufacturer of hydraulic filters.pdf.ppt. Final Report (. the powerpack. Relevant Links 1. 2. MP Filtri (who provided the filter necessary for the valves). John Potzold and Kwai Chan for their valuable advice regarding the fabrication. Other cool projects by the Mechatronics 2009 class 5. 2009 B est m atches f or a r eport o nh ydraulic r obotic a rm . Good explanation of current fluid power technologies and fluid power design here and here Last Updated: April 8.8MB) – Completed on April 6. 17. Poster (. Rick Churilla for his help in getting me sponsorship from Parker. Design Report (. 2008 5. 1. 2MB) – Completed on Dec.5 MB) – Displayed at the symposium on March 23. Documents 1. Andy Barbor for his advice on the electronics. Preliminary Design Presentation (. 15. Rob Chin for his help in getting me sponsorship from MP Filtri.4MB) – Presented Sept. 1. 2008 4. 2009 3. 9MB) – Presented Nov.Sponsors This project would not be possible without generous donations from Parker Hannifin Corporation (who provided the valves and the cylinders). Video of Schunk modular robot arm 6.pdf. 2 MB).Am ore d etailed d escription o ft he d esign c an b ef ound i nt he d esign r eport (.pdf. J ump t ot ext » .