omg-heat-tracker

Purpose

The purpose of this project is to provide our local flyball club with a heat tracker. The heat tracker is used to keep track of which heat we are currently on during a flyball race. A race is usually a best 3 out of 5 heats, or a 4 out of 4 heats. This keeps track of which team won which heats.

Notice

The following is provided without support. Use it at your own will/risk.

Design

The heat tracker is simply composed of 5 lights, in a wooden box and looks something like this:

It is built using relatively cheap components. A custom PCB, detachable-esp8266-4x-wire-to-board, provides a somewhat better way to connect a development ESP8266 board, in this case a LOLIN (WEMOS) D1 R2, to a few lights (in this case 5 x 7 LEDs controlled by a WS2812B), with a DC power jack.

API

A REST API is provided by the ESP8266 which exposes endpoints used by the browser based remote. The current endpoints are as follow:

Remote

The root endpoint, /, provides the browser based remote that makes calls to the other endpoints

Retrieve all heats

Retrieves a list of all of the heats and their results. It will always return TOTAL_HEATS elements.

• URL: /heats
• Method: GET
• Success Response:
  • Code: 200
    Content: [ 'left', 'right', 'tie', 'none', 'none ]
  • Code: 200
    Content: [ 'left', 'left', 'right', 'left', 'none ]
  • Code: 200
    Content: [ 'none', 'none', 'none', 'none', 'none ]
• Sample Call:

  curl -H "Accept: application/json" -i http://192.168.4.1/heats

Set current heat results

Sets the results for the current heat.

• URL: /heat

• Method: POST

• Data Params This method takes in JSON, with only one property: result

      {
          "result": "left"
      }

  The valid values for result are: left, right, tie

• Success Response:

  • Code: 201

• Error Response:

  • Code: 400
    Content: { "error": "Invalid JSON body." }

• Sample Call:

  curl -d '{"result": "right"}' -H "Content-Type: application/json" -X POST http://192.168.4.1/heat

Reset race

Resets all heats, starts a new race.

• URL: /heats
• Method: DELETE
• Success Response:
  • Code: 200
• Sample Call:

  curl -H "Content-Type: application/json" -X DELETE http://192.168.4.1/heats

Reset last heat

Resets the last heat, in case it was done by mistake.

• URL: /heat/last
• Method: DELETE
• Success Response:
  • Code: 200
• Error Response:
  • Code: 400
    Content: { "error": "Cannot undo heat, currently on first heat." }
• Sample Call:

  curl -H "Content-Type: application/json" -X DELETE http://192.168.4.1/heat/last

OmgHeatTracker.ino

This provides the Arduino compatible code to control the lights. It provides the application logic in order to set the lights according to the heats' results, and provides a way to restart the race. Currently, this is meant to be controlled with a browser, by connecting to an access point broadcasted by the ESP8266. The IP address of the ESP8266 defaults to 192.168.0.1.

detachable-esp8266-4x-wire-to-board

Optionally, one can use this PCB (done in EAGLE) in order to facilitate how the LEDs are connected to the LOLIN D1 R2. This provides a PCB that has the LOLIN D1 R2 on headers, 5 x board connectors and a DC power jack. It makes it easy to swap the LOLIN D1 R2 and the lights.

TODO

• Add programs, ie: best 3 out of 5, 4 out of 4, etc.