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movehub-async

movehub-async

Asynchronous methods for the Lego Boost Move Hub package

movehub async

npm version

Simple to use asynchronous methods for the Lego Boost Move Hub

Setup

$ npm install movehub-async

Usage

const boost = require('movehub-async');
 
const hub = await boost.getHubAsync();
 
// Turn light from red to green
await hub.ledAsync('red');
await hub.ledAsync('yellow');
await hub.ledAsync('green');
 
// Turn A & B motors for 10 seconds with power 20
await hub.motorTimeMultiAsync(10, 20, 20);
// Turn motor C 600 degrees with power 5
await hub.motorAngleAsync('C', 600, 5);

It is also possible to wait that motor execution has stopped

await hub.ledAsync('red');
// Continue when led is red
await hub.motorTimeMultiAsync(10, 20, 20, true);
// Continue 10 sec later
await hub.motorTimeMultiAsync(5, 20, 20, true);
// Continue 5 sec later
await hub.motorAngleAsync('C', 800, 50, true);
// Continue some time later
await hub.ledAsync('green');
// Continue when led is green

Package contains also simple methods to drive for a specified distance and turn a specified angle. By default drive and turn methods will wait the execution has stopped.

// Drive 2 meters forward
await hub.drive(200);
// After 2 meter drive, turn 90 degrees to the right
await hub.turn(90);
// Drive 1 meter backwards
await hub.drive(-100);
// Turn 180 degrees to the left
await hub.turn(-180); 

API

Check complete non-async API definition from Lego Boost Move Hub. Asynchronous version of the method has an Async-suffix in the name, e.g. motorTimeMulti -> motorTimeMultiAsync.

Boost

boost.getHubAsync()

Create a connection to the Hub. Internally calls bleReadyAsync, hubFoundAsync and connectAsync.

const hub = await boost.getHubAsync();

boost.bleReadyAsync()

Wait for BLE device to be ready.

await boost.bleReadyAsync();

boost.hubFoundAsync()

Wait for MoveHub found event.

const connectDetails = await boost.hubFoundAsync();

boost.connectAsync(connectDetails)

Initialize and wait for the connection to the Hub.

const hub = await boost.connectAsync(connectDetails);

Hub

hub.ledAsync(color)

Control the LED on the Move Hub.

await hub.ledAsync('red');

hub.motorTimeAsync(port, seconds, dutyCycle = 100, wait = false)

Run a motor for specific time. Await returns when command is sent to Hub.

await hub.motorTimeAsync('C', 5, 50);
// Continue almost immediately when command is sent to Hub
 
await hub.motorTimeAsync('C', 5, 50, true);
// Continue 5 seconds later

hub.motorTimeMultiAsync(seconds, dutyCycleA = 100, dutyCycleB = 100, wait = false)

Run both motors (A and B) for specific time. Await returns when command is sent to Hub.

// Drive forward for 10 seconds
await hub.motorTimeMultiAsync(10, 20, 20, true);
// Continue 10 seconds later

hub.motorAngleAsync(port, angle, dutyCycle = 100, wait = false)

Turn a motor by specific angle. Await returns when command is sent to Hub.

// Turn ~180 degrees  
await hub.motorAngleAsync('B', 980, 100, true);
// Continue after the turn

hub.motorAngleMultiAsync(angle, dutyCycleA = 100, dutyCycleB = 100, wait = false)

Turn both motors (A and B) by specific angle. Await returns when command is sent to Hub.

// Drive forward
await hub.motorAngleMultiAsync(500, 100, 100);
// Continue immediately after command is sent to Hub

hub.drive(centimeters, wait = true)

Drive specified distance. By default drive-method's return promise will resolve when the distance has been driven.

Note: Drive method is implemented with Lego Boost Vernie

// Drive forward 2 meters
await hub.drive(200);
// Continue after drive is finished

hub.useMetricUnits()

Use metric untis in drive-method. Metric is default.

// Drive forward 200 cm
await hub.drive(200);
 
hub.useImperialUnits();
 
// Drive forward 200 inches
await hub.drive(200);

hub.useImperialUnits()

Use imperial units with drive-method.

hub.setFrictionModifier(modifier)

If drive method's distance is not correct, friction modifier can be changed.

// Drive forward 100cm
await hub.drive(100);
 
// Distance was only 90cm, update modifier
hub.setFrictionModifier(1.1);
 
// Drive 100cm
await hub.drive(100);

hub.turn(degrees, wait = true)

Turn specified angle to either right (positive number) or left (negative number). By default turn-method's promise will resolve when the angle has been turned.

Note: Turn method is implemented with Lego Boost Vernie

const hub = await boost.getHubAsync();
// Drive 1 meter square
await hub.drive(100);
await hub.turn(90);
await hub.drive(100);
await hub.turn(90);
await hub.drive(100);
await hub.turn(90);
await hub.drive(100);
await hub.turn(90);

hub.driveUntil(distance = 0, wait = true)

Drive until the sensor shows an object in defined distance. The distance sensor is not very sensitive or accurate. By default the bot will stop when the sensor notices a wall for the first time. Sensor distance values are usualy between 110-50.

await hub.driveUntil();

hub.turnUntil(direction = 1, wait = true)

Turn until sensor doesn't detect any blocking object. 1 or any positive number turns to the right (default) and 0 or any negative number turns to the left.

// Turn to the right
await hub.turnUntil();
// Turn to the right
await hub.turnUntil(1);
// Turn to the left
await hub.turnUntil(0);

Example project

lego-boost-ai has a simple AI and manual controls for Lego Boost.

Tester

tester.js

Use development version

It is possible to use development version from GitHub, which may contain unreleased features.

$ npm install git+https://[email protected]/ttu/node-movehub-async.git

Changelog

Changelog

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

License

Licensed under the MIT License.