DistanceSensor

The LEGO® Education SPIKE™ Distance Sensor behaves like a conventional ultrasonic range finder but also has four LEDs that can be used to create the “eyes” of a robot. Each LED can be controlled individually.

class buildhat.DistanceSensor(port, threshold_distance=100)

Distance sensor

Parameters:: port – Port of device
Raises:: DeviceError – Occurs if there is no distance sensor attached to port

callback(func)

Set callback function

Parameters:: func – Callback function

property connected

Whether device is connected or not

Returns:: Connection status

static desc_for_id(typeid)

Translate integer type id to something more descriptive than the device name

Parameters:: typeid – Type of device
Returns:: Description of device

property description

Device on port info

Returns:: Device description

deselect(): Unselect data from mode

property distance

Obtain previously stored distance

Getter:: Returns distance
Returns:: Stored distance

eyes(*args)

Brightness of LEDs on sensor

(Sensor Right Upper, Sensor Left Upper, Sensor Right Lower, Sensor Left Lower)

Parameters:: args – Four brightness arguments of 0 to 100
Raises:: DistanceSensorError – Occurs if invalid brightness passed

get()

Extract information from device

Returns:: Data from device
Raises:: DeviceError – Occurs if device not in valid mode

get_distance()

Return the distance from ultrasonic sensor to object

Returns:: Distance from ultrasonic sensor
Return type:: int

property interval

Interval between data points in milliseconds

Getter:: Gets interval
Setter:: Sets interval
Returns:: Device interval
Return type:: int

isconnected()

Whether it is connected or not

Raises:: DeviceError – Occurs if device no longer the same

mode(modev)

Set combimode or simple mode

Parameters:: modev – List of tuples for a combimode, or integer for simple mode

property name

Determine name of device on port

Returns:: Device name

static name_for_id(typeid)

Translate integer type id to device name (python class)

Parameters:: typeid – Type of device
Returns:: Name of device

off(): Turn off sensor

on(): Turn on the sensor

reverse(): Reverse polarity

select()

Request data from mode

Raises:: DeviceError – Occurs if device not in valid mode

property threshold_distance

Threshold distance value

Getter:: Returns threshold distance
Setter:: Sets threshold distance
Returns:: Threshold distance

property typeid

Type ID of device

Returns:: Type ID

property typeidcur

Type ID currently present

Returns:: Type ID

wait_for_in_range(distance)

Wait until object is closer than specified distance

Parameters:: distance – Distance

wait_for_out_of_range(distance)

Wait until object is farther than specified distance

Parameters:: distance – Distance

property when_in_range

Handle motion events

Getter:: Returns function to be called when in range
Setter:: Sets function to be called when in range
Returns:: In range callback

property when_out_of_range

Handle motion events

Getter:: Returns function to be called when out of range
Setter:: Sets function to be called when out of range
Returns:: Out of range callback

Example

"""Example for distance sensor"""

from signal import pause

from buildhat import DistanceSensor, Motor

motor = Motor('A')
dist = DistanceSensor('D', threshold_distance=100)

print("Wait for in range")
dist.wait_for_in_range(50)
motor.run_for_rotations(1)

print("Wait for out of range")
dist.wait_for_out_of_range(100)
motor.run_for_rotations(2)


def handle_in(distance):
    """Within range

    :param distance: Distance
    """
    print("in range", distance)


def handle_out(distance):
    """Out of range

    :param distance: Distance
    """
    print("out of range", distance)


dist.when_in_range = handle_in
dist.when_out_of_range = handle_out
pause()