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Team Status Report for 3/4/2023

The most significant project risk at this point is successful integration of various components. We are making good progress on getting individual components working, but because there are so many hardware and software elements it will be a challenge to complete this on time. For mitigation, there’s not a ton we can do, other than adhere to the schedule and use the built-in SLACK time as necessary; though we have obtained backup items in case the Jetson Xavier AGX and/or SLAMTEC LiDAR do not meet our requirements.

There were no major changes to the overall design or its requirements since the last status report. Our current implementation details can be found in the full design report.

As a team we spent most of our time this week on the design report, so that’d be the biggest artifact produced. We have also got a POC for SLAM running  on the Jetson using ROS and hector SLAM.

Q: As you’ve now established a set of sub-systems necessary to implement your project, what new tools have your team determined will be necessary for you to learn to be able to accomplish these tasks?
A: As we have transitioned from using Matlab to ROS, the team must learn ROS as it will be the framework used for controlling the robot and implementing SLAM.

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Zach’s Status Report for 2/25/2023

  • Week recap
    • CAD models for the lift system
      • 3D print gears to get our desired torque output from the steppers (each stepper needs to lift 5lbs)
      • Initial version of complete, and will be submitted for fabrication on Monday (see image below)
      • Plan is to mount these between 1/4″ plywood panels that will make up the arms of our lift system
      • Decided on using cams fixed to large gear to lift bins for easy positioning
    • Roomba driving
      • Was having trouble getting it to enter serial communication mode
      • Potential default baud rate issue (115200 stated in documentation)
      • Using special boot procedure for reliable 19200 baud comms
      • Tethered driving with computer: Drive Code v0

  • Schedule
    • Slightly behind on CAD for docking system
      • Good trajectory this past week, which will be carried forward
      • Validate prototype gears and move to full version with cams (rapid progress here)
    • Getting more used to Solidworks again
    • George assisting with stepper motor control
    • Any redesign work can happen over spring break and use slack time for further testing
  • Deliverables next week
    • Working prototype of the pickup arms, with mount points for gears
    • Gear system validation
    • If gear testing is successful, make/print the next iteration with cams, otherwise make gearing changes to reach target lift capacity
    • May write code with a simpler interface for roomba driving, with more customization on motor speeds (dependent on other group member needs)
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Team Status Report for 2/25/2023

The current risks and their associated mitigations are listed below:

  • Jetson Xavier AGX ethernet connection is unreliable. We’re attempting to reconfigure the computer but mitigation plan will be to switch to the Jetson Xavier Nx.
    • Last year’s team that worked with the Roomba used a Xavier Nx for their Project, and seemed to have less problems
  • Stepper motor gearboxes are quite expensive, and purchasing them would put us a bit too tight on budget. We’re looking at 3D printing gears instead to achieve a lift weight that meets design requirements. If this fails, another lift mechanism will have to be created.
  • SLAM/LIDAR: After reflashing the Jetson, it has successfully connected to Matlab. Some Matlab LIDAR api calls were built for the Jetson, but a full build has not been attempted with all possible api calls.  In case full build does not succeeded, will attempt ROS slam.

There have been no major project changes yet, but pending the success of 3D printed gears we may have to redesign the lift system. [Add anything else]

We haven’t changed our project schedule, but there has been more collaboration on different tasks than just 1-2 group members. Notably, all 3 of us worked together on the Roomba’s tethered driving. Task fill and assistance is listed below:

  • All 3 of us supported Roomba bringup
  • George will help Zach with stepper motor control
  • [Others?]

Project successes this week:

  • USB camera calibration and distance detection
  • Roomba drive control
  • Jetson reflashed
  • Matlab LIDAR: Jetson conected to Matlab, Matlab -> Cpp test build on Jetson succeeded.

[Drop in photos/links if we want]

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Team Status Report for 2/18/2023

Risks: LIDAR data processing/path planning, attachment points to Roomba for compute package and docking system, and others maybe? Contingency: Pivot to other open source Lidar packages, or worst case pivot to overhead camera and network call procedure.  Docking mitigation is no bin lifting and wheels instead

Design changes: consolidate power system into 1 large battery pack, power USB devices through Jetson. Use Matlab for CV things, and convert to C.

Updated schedule: added more slack post-spring break for component design and test. Re-ordered LIDAR bring-up and path planning simulation.

Engineering principles: Worst-case analysis for power, Reliability for pickup mechanism, KISS for picking the SLAM libraries that we are using.

Documentation: Git history changes can be found https://github.com/gxgao/eceCapstone

 

 

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Zach’s Status Report for 2/18/2023

This week I spent most of the time gathering information on the power requirements of our design, and started considering mechanical design elements as well. For power I was originally planning to have separate buses at 2 or 3 different voltages, but decided to have a single 12V supply that powers both the Jetson and the stepper driver, and get power for the LIDAR and USB cameras via Jetson USB. I also ordered the stepper motors we’ll be using for the project, and explored a Roomba CAD model that I will design around.

Currently I’m slightly behind schedule on the mechanical bin design since I didn’t allocate time for developing the power system. With the Roomba acquired I’ll be much faster at designing the docking mechanism in CAD, so I plan to catch up this week. This isn’t a major issue since I have a week of slack built into the hardware development.

In the next week, I’m targeting having the bin attachment complete, and also having the Roomba attachment designed and possibly fabricated. I’ll need to ether leave room for or integrate the electronics mounts as a part of the docking mechanism.

Courses used for my design portion: 18-021, 18-100, 18-220, 24-104. The analysis for power was not too complex, but just had to reason through the ratings for our various components. Knowing how to use GPIO (Jetson) to drive larger items (steppers) came from non-work experience.

 

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Zach’s Status Report for 2/11/2023

This week, I considered tradeoffs of various bin docking designs in concert with discussions on the robot navigation methods. At this point I’m leaning towards an omnidirectional mechanism since it makes the navigation easier, although the mechanical design is a bit more complex as a result.

I also helped put together an initial parts list and select components that we wanted from the ECE inventory.

Knowing that we weren’t going to have a lot of work time this week due to the proposal presentations, I didn’t schedule any significant tasks, so we are on schedule.

In the next week, my primary goal will be to design in CAD and hopefully fabricate the omnidirectional mechanism, as well as make changes if any are needed. If time allows, I may design in CAD an alternative mechanism that’s not omnidirectional in case our current idea fails to meet design requirements.

 

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Team Status Report for 2/11/2023

The most significant risk for our project at this point is acquiring a LIDAR camera from the ECE parts inventory that’s suitable for our needs. We’re choosing to use an Intel RealSense camera as opposed to a 360-camera since any trash bin will cause a significant obstruction that we have to process away as not being a wall or other flat obstacle. Based on background research, we think mapping with a fixed FOV camera will provide acceptable performance.

Another risk at the moment is going to be the docking mechanism, which we discussed in detail on Wednesday following the proposal presentations. We’re thinking about using an omnidirectional system to avoid alignment complexity with the robot’s movement. We believe this will save time and help us to meet/exceed our design target.

We didn’t make any design changes this week, and are on schedule with respect to the timeline in our proposal.

Our project includes considerations for economics and general welfare. The automated system is intended to relieve the workload on janitorial staff, and allows them to focus and invest time in other tasks. Regardless of the system, bins must be emptied to maintain a private and healthy office environment.

We started putting together a parts list and submitted our first request from the ECE inventory! Yay!