how to create line chart and appear data use kickchart in rails?

I have column called speed in table Speed. I need to create a line chart group by minute (created_at) and point appear speed.

For example p1 (110.4) , p2 (113.5), and more.

There can be many values of speed.

in SpeedController.rb

 def index
    #@speeds = current_master.speed.all

    @spee = Speed.where(id_watch: current_master.id_watch)
    }
  end

in speed.html.erb

This line occur error

<%= line_chart @spee.group_by_minute(:created_at).average(:speed) %>

when write <%= @spee.inspect %> for example

#<ActiveRecord::Relation [#<Speed id: 1, id_watch: "hello@hello.com", speed: 79, created_at: "2018-06-23 08:02:00", updated_at: "2018-06-23 08:02:00", master_id: 1>

want draw like this