Assembly - Traffic Light

What you will need

• Traffic light components (Duckietown project shop)

• An appropriately configured SD-card.

• Tools: (strong) wood glue or hot glue gun, tape, double-sided tape.

What you will get

• An assembled traffic light in configuration DT21-TL (latest) or previous legacy versions.

This section describes the physical assembly and installation of traffic lights.

Overview

Traffic lights are crucial elements of modern cities, and in Duckietown, they play a similar role by ensuring well-organized traffic.

They can serve as:

1. Centralized coordinators of traffic at 3- or 4-way intersections in Duckietown.

2. Components of a Duckietown Autolab watchtower network.

Attention

For Duckiebots to recognize traffic lights governing a specific intersection, appropriate signage must be placed (traffic light traffic sign instead of a stop sign).

• Hardware Design: Traffic lights are “Duckiebots without wheels,” housed in a distinct chassis.

• Structure: They consist of two supports connected by an overhanging tube, with one support containing the computational stack and an overseeing camera.

• Placement: Traffic lights are positioned diagonally at intersections.

Hardware Assembly

• For latest configuration traffic lights, refer to the instructions:

  • Assembly - Traffic Light DT21-TL

• For legacy builds (prior to TL21), follow these instructions:

  • Assembly - (Legacy) Traffic Light DT18-TL.

SD card image Preparation

At the software level, traffic lights function similarly to Duckiebots. When initializing the SD-card, follow the Duckiebot SD-card initialization instructions, ensuring that you use the --type traffic_light option.

Wi-Fi configuration for traffic lights is not set by default. To enable it, use the --wifi option as described in the instructions.

Example command for a Wi-Fi connected traffic light:

dts init_sd_card --hostname ROBOTNAME --country COUNTRY --type traffic_light --configuration TL21

Note

For Autolab users: Use the convention hostname: watchtowerXX, where XX are incremental numbers.

• For standard traffic light setup, use:

  • hostname: trafficlightXX

• Login account:

  • Username: duckie

  • Password: the value entered when DTS prompts during initialization

Warning

For Autolab users, retain the duckie username and record the password for each device.

Traffic Light First Boot

Once the traffic light is fully assembled, turn it on and follow the first boot procedure, and once finished update the software with:

dts duckiebot update ROBOTNAME

If prompted, select robot type = duckiebot and robot hardware = raspberry_pi. Wait for the update to finish and reboot the device.

The blinking behavior should then start automatically.