Final Proposal / Weekly Update

Response to Feedback

  1. We’ll be making a pair of laser tag bots.We decided start 3D printing the base next week. This change is reflected in our schedule, and CAD models can be found below.
  2. We chose to use RF transceivers. Since neither of us has much experience at all with wireless communication, and because they were an inexpensive option with significant online support, we decided this was the best method.
  3. We definitely plan to keep our scope manageable. We assured that the milestones for the last three weeks of the semester before the project fair were all related to features of the advanced design so that if the base design takes longer than planned, we'll still be able to have a functioning product by the time of the fair.
  4. We've looked a little bit into IR communication protocols. We researched how laser tag arenas modify their IR signals to extend range and encode shooter data. Tyler also has a little experience with how toy laser tag signals work. We ordered some long range IR emitters and plan to get deeper into the encoding of the signals in two weeks.

Revised Project Proposal

High-level description


We’ll be making a pair of laser tag bots. As a minimum viable product, we will have two radio frequency controllers, each with a joystick for movement and a fire button, along with two mobile robots. The robots will be able to fire on one another (using IR emitters and receivers), and will emit a signal back to the remote to indicate that it has been shot. We plan on incorporating an LCD display of health and ammo remaining.

Our goal for the product is to make the laser tag robot modular so that users can customize their fighter for battles with their friends. We want to be able to exchange attack pieces (i.e. long range, more ammo, swivel cannon, freeze shots, etc.), and potentially some defense pieces as well (such as a shielding device). It would also be nice to have the controller LCD display user messages. Regardless of how many peripheral functions we’re able to add, we want to make the product scalable so that more than two robots could play in the same battle. To add finish to the product, we hope to add lights, sounds, and potentially vibration to the robots and controllers.

Required Elements


For our most basic design, we’ll end up using (per robot/controller pair):
  • RF transceiver modules for remote and robot
  • Two geared DC motors for robot mobility
  • 180 degree servo for the “laser turret”
  • IR LED and potentially a lens for the turret
  • IR receiver arrays for detecting hits
  • LCD display for Health/Ammo HUD on controller
  • Joysticks and buttons for controller input
  • 2 microcontrollers (Arduino Nanos) for each robot/controller pair
For more complicated designs:
  • Piezo buzzers or small speakers for audio feedback
  • Vibration motors for haptic controller feedback
  • Modular laser/shield attachments

Our software will have to implement the following:
  • RF communication protocols between multiple robot/controller pairs
  • IR communication protocols to communicate team, damage, and other information

New Elements

We plan on learning the following new concepts for our project:

  • RF communication (including software and hardware)
  • IR communication
  • Joystick and button input
  • LCD displays
Milestone
Date
Project Proposal
January 18
Meet With Dr. Colton, Order All Necessary Components
January 25
Finalized Proposal, Preliminary CAD Drawing, Functional RF Code
February 1
Hardware Prototype, Complete Remote Breadboard
February 8
IR Breadboard, Order Remote PCBs
February 15
Mobile Base, Simple Robot Housing
February 22
Consistent RF Functioning
March 1
Consistent IR Functioning (Target Distance)
March 8
CAD Controller Drawing
March 15
Final Housings
March 22
Modular Pieces (hardware)
March 29
Modular Pieces (software)
April 5
Project Fair
April 12

Weekly Progress Report

We made quite a bit of progress in the last two of weeks. In fact, we're even ahead of where we wanted to be. Last week, we ordered most of the materials we plan on using, including joysticks, buttons, LCD displays, RF transceivers, geared motors, and IR LEDs. After experiencing signifiant issues with the RF transceivers, we were able to find a working library and a working pair of transceivers that could send and receive signals successfully. We included a video of the results below. Note in the video that although the two Arduino devices are on the same breadboard, there exists no connection other than the RF transceivers.


As per Dr. Colton's feedback, we decided to modify our milestone schedule to begin the manufacture and testing of the robot base earlier than originally planned. We began by making a basic CAD model. Images of the model can be seen below.

The first preliminary assembly capture above shows the entire robot. We plan to 3D print the majority of the components. In the final assembly, we plan to include ports for IR receivers as well as more IR emitters on the outer housing. The cut view shows the base, the motors, and the connection of the outer housing. The majority of the components will be connected with press fits. The servos will be screwed into the upper tower, and the PCB, battery, and other electronics will be placed toward the front of the robot. We plan to attach the outer housing with a snap fit, allowing users to interchange housings with different colors, shapes, weapon ports, and/or IR receiver placement.

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