tmp.plantuml

' https://plantuml.com/zh/
@startuml
header 20210411
title 心如止水
skinparam sequenceArrowThickness 2
skinparam roundcorner 20
skinparam maxmessagesize 60
skinparam sequenceParticipant underline
actor User
participant "心跳感測" as A
participant "arduino" as B
participant "馬達" as C
User -> A: 觸碰
activate A
A -> B: 心跳數
activate B
alt 心跳數高於平均心跳數
    B-> C: 啟動
else 心跳數等於小於平均心跳數
    B-> C: 停止
end
@enduml