In this post, we will outline our Jam Week goals and describe our daily progress as we developed our project.

Goal:

By the end of Jam Week, we will make a radio-controlled (RC) 3 wheeled robot. The long-term goal of this project is to have a high-quality BB-8 robot working.

Stretch Goals

• Have the robot rolling around in the sphere
• Have audio and tilt sensors working
• Have a design for the arm for guiding the head designed

Preparation

The parts were ordered online almost a month beforehand. Major components were:

1. 6 Channel Radio Control
2. Arduino Mega (Lots of channels for controlling individual parts)
3. Motors/Gearboxes
4. Motor Controllers
5. Omni-wheels (Wheels that slip in one direction, can apply power in another)
6. Tilt Sensor
7. Audio Controllers
8. 2 20 inch half spheres
9. 12 volt battery

Parts Laid Out

The Half Spheres

(Trust us, there’s two.)

Framework Modeling

Adam had some free time before Jam Week, so he made a SketchUp drawing of what he expected the frame to look like.

Which was then disassembled to be cut out on the laser cutter.

Day 1 - Monday

First thing we did was test each of the individual components. We made sure we could program the Arduino, that the motors would spin, and that the Arduino board could be controlled by the 6 channel controller. We also prepped the wood to be cut by the laser cutter at the tech shop.

A big part of the day was spent laying materials out, putting a plan together for the next day, as well as putting together a plan for the week. We used SketchUp to layout the plans for the pieces of wood that would be used for the frame.

We identified the following issues:

• Our motors are not fast enough at 100 RPM Output (1000 RPM Output motors were ordered off of Amazon, and were expected to arrive Wednesday)
• Sealing the 2 semi-spheres together could be problematic (Contact paper will be used temporarily to test the sphere)
• The weight of the robot inside the sphere will need to be heavy enough to ensure that it will not flip inside the sphere, but light enough to be supported by its wood frame (We will not be able to test this until the frame is built, and the sphere is sealed. Wiring will have to be completed as well)

We were able to get goals together, as well as a shopping list for the next day.

Day 2 - Tuesday

The day started out with a trip to Lowe’s to get contact paper, as well as a trip to the Pittsburgh TechShop to laser cut the wood for the base of the robot. After the parts were assembled, we added a temporary board to the top of the robot to hold the electronics pieces.

We also started the initial programming for the Arduino, the device which translates input from the RC receiver into signals that operate the motor controllers. The left joystick on the transmitter, which sends data on RC channels 1 and 2, controlled the forward/backward motion and left/right motion respectively. The right joystick was saved for tilting the yet-to-be-completed head, while the top to spin controls would be used for turning the head and playing sounds.

Day 3 - Wednesday

Today we received the new faster motors we ordered on Monday, so we installed them and again tested them.

We also tested the robot in the ball, using contact paper to seal it temporarily. This also required a new temporary electronics board holder, which was jury-rigged from cardboard and duct tape. If we hadn’t used duct tape in the project, it clearly would have all failed.

We found that there were some control issues that we would sort out on Thursday morning.

We also started designing the “pillar,” which would stand at the center of the robot and hold the electronics on platters, and eventually hold the “neck” of the robot. The neck would be responsible for keeping the head of the robot aligned, using magnets running on the inside of the ball. Those magnets would keep a metal piece in the head rolling on the top of the ball.

After a late night run to the laser cutter, we had pieces for platters that would slide onto the pillar and hold the electronic boards.

Day 4 - Thursday

The day started with another rebuild of the robot, now with the pillar and plates for holding the electronics.

Much of this day was spent thinking about the neck controls and designing a way to keep the sphere halves connected. Late in the day, we designed a box to hold the servos and the frames for moving the arm.

Day 5 - Friday

The last day was working toward our stretch goal of getting a “neck” setup for the top of the pillar. We got it assembled, and realized the design had some spacing issues for the servos, and therefore didn’t install it.

It will have to wait for a redesign.

Moving forward

The long term goal of this project is to have a high quality BB-8 robot working and ready for the movie release in November. To that end, we have the following problems/steps we need to complete.

1. A sealing system for the ball. The batteries need to be replaceable, and the robot needs to be able to move around freely. The assumption at this point is that we will need to build a “easter egg” like system for easy opening and closing of the ball.
2. A working arm and head guiding system. We need to complete the servo controlled arm and a mounting system.
3. A rolling head, with matching magnets to be guided by 2. This will require antenna, optical sensors and some lights.
4. Audio system. Having 2 channels of audio for background and sound effects.
5. Hacking the 6th channel for activating the audio effects. This will require an additional Arduino on the controller, as well as several buttons for triggering.
6. Final paint on the ball and the head