private void button2_Click(object sender, EventArgs e)
{
chart1.Series.Add((++ser).ToString());
chart1.Series[ser].ChartType = SeriesChartType.Line;
chart1.Series[ser].BorderWidth = 3;
chart1.Series[ser].Name = "实际速度曲线" + ser.ToString() + " " + V0.ToString();
fspeed = V0;
jiasudu = hjjsd;
label7.Text = jiasudu.ToString();
timer1.Start();
timer1.Enabled = true;
}