Interactive Telerobotics Exhibit

The goal of this project is to develop a robotic arm for an exhibit placed in the Discovery Center that will provide users with a first-person perspective of a remote workspace and allow them to interact with objects from a distance in order to complete a task. The robot workstation will have a tethered stationary base with sufficient degrees of freedom to manipulate (pick, orient, and place) objects of interest. The system will be capable of use with a specific task, such as stacking compliant objects, or playing a simple board game.

Objective
 Phase I (2017-2018 cycle): develop a single-user prototype of the telerobotic master/slave setup and validate function and durability. Phase II (2018-2019 cycle): extend the Phase I prototype to a mutli-user setup where 2 or more individuals can collaborate and/or compete in task completion.  

Required
 Safety of users and spectators at all times Robust design that withstands interaction by users of all ages and minimizes maintenance Intuitive design that allows users of all ages to easily and quickly understand the interfaces of the exhibit Maximal use of standard parts for replacement and repair ADA compliant and physically accessible to a range of heights from small children to adults</li> Minimal staff supervisions while on exhibit</li> Fit within 36" cube</li> Mobile (fit through a door frame and be movable with two people)</li> Internal mechanisms should be largely visible</li> </ul>

Preferred
 User vision of the exhibit should be restricted and user should be provided some form of 3D vision of the work space</li> Haptic feedback to the master controller</li> Large output device of visual feedback for spectators</li> </ul>

Robotic Arm
After researching robotic arms and the process of designing and assembling one, we decided to look into an open source option. This would allow us to have a good starting point much quicker than if we designed an arm from the bottom up. Many open source options also are made of 3D printed parts, which would allow our client to easily replace parts of the arm. We will then later make modifications to the arm to fit our design specifications. Below are two options we narrowed our design down to.

BCN3D Moveo
The BCN3D Moveo is an open source arm with 5 degrees of freedom. All pieces of the arm are 3D printable. The arm uses steppers and servo motors for movement and is controlled by an Arudino Mega. This arm was a serious consideration, but due to a lack in documentation and having one less degree of freedom than we wanted, we decided not to go with this option.

THOR
THOR is an open source arm with 6 degrees of freedom. This arm has 3D printable parts and users steppers and servo motors for movement. THOR is controlled using an Arduino Mega and uses an open source gcode-base firmware. One thing that put THOR in front of many other open source options we found was the extensive documentation of the development process. The THOR arm what we've decided to begin our robotic arm design with.

Controller
One of our biggest challenges has been coming up with a controller design that works well and fits all of our specifications. Intuitiveness is a key aspect of controller design, as we want any patron of the Discovery Center to easily understand how to use our controller and be able to use it effectively.

Medical Focus Controllers
These are some of the first controllers we encountered during our research. Controllers of this type are mainly used in the medical field. This category includes controllers such as the Geomagic Phantom Omni and Force Dimension Omega-3. These controllers are very intuitive and offer upwards of 7 degrees of freedom which works with our arm perfectly. The issues we found with controllers in this category is that they have extremely high price points that don't fit in our budget. Another large issue is that these controllers seem to be very fragile which does not fit our design specification. We decided to not go with any controller in this category as even though many of them did fit what we were looking for in a controller, they didn't work with our design specifications.

Master/Slave Controller Setup
The Master/Slave controller setup uses a master controller very similar in design to the robotic arm in order to control the slave (robotic arm). This was a design we had been researching since the start of the project. The issue we were finding with this design was finding a way to design a master controller that was intuitive to use. Designing a second arm similar to our robotic arm wouldn't easily allow the user to move the arm effectively due to the amount of degrees of freedom we have. While researching this type of design, we found a design from TeleroboticsCAR. Their design allowed the user to control all degrees of freedom without running into any restrictions. Their controller also allowed for haptic feedback using the handheld part of thee controller. This is currently one of the designs we've decided to focus on.



Leap Motion
The Leap Motion controller is a controller main used alongside virtual reality devices like the Oculus Rift. It can be used as a standalone device to track a user's hand and lower arm. It uses two monochromatic IR cameras ans three infrared LEDs to track in a hemispherical area, to a distance of about 1 meter. This device is something we've received great reception about from users at Snapshot Day and from our client. It is another design we've decided to go ahead and focus on. There are a few issues we've seen from other designs that have used the device and from our own testing. Issues such inaccurate tracking and lag have been seen, but we've also seen the design work extremely well. We'll have to address these issues during testing.