PCB genesis短槽加引导孔实现方法

一.何为短槽

短槽通常定义:槽长小于2倍槽宽      如：槽长1.8mm,槽宽1.0mm

二.为什么要加短槽加引孔呢

短槽孔在钻孔时孔易偏斜导致槽长偏短, 当槽长宽比越小,则受力越不均匀,在钻第2个孔时,钻头两边受力不均匀再加上是顺时针旋转，会导至第2个孔往逆时针方向偏转且变短(如下图）

短槽偏位问题如何解决呢，在我们PCB行业最佳作法是在钻槽孔之前，先在槽孔两端2个小孔(如下图).

PCB行业已有很多短槽加工方法了

具体方法请链接：PCB钻孔--超短坑槽的加工方法

机械钻孔中的短槽孔加工技术

短槽孔加工技术

三.加短槽引孔实现原理

求解思路

1.已知短槽宽1.0mm与短槽2点坐标
2.求出槽长=槽中心距0.8 + 槽宽1.0=1.8mm
3.求出引孔大小=(1.8-0.2)/2 =0.8mm
(0.2为2个引孔间距, 孔径向下取整为钻刀大小)
4.求出短槽的线拉伸距离=
（槽长1.8- 引孔大小0.8mm）-槽中心距0.8mm=0.2mm
5.求引孔坐标，在短槽2点坐标为一条线，在的基础上拉伸0.2mm即可,每边各拉0.1mm，即可得到引孔坐标（下面代码有提供线拉伸函数）

四.C#简易代码实现:

1.加短槽代码

            #region 短槽加引孔  ydkdrl
            List<gL> SlotList = glayer.Llist.Where(tt => ((calc2.p2p_di(tt.ps, tt.pe) + tt.width * 0.001) / (tt.width * 0.001)) < ).ToList();
            if (SlotList.Count() > )
            {
                if (!g.Check_Layer_Exist("ydkdrl")) g.CreateLayer("ydkdrl");
                g.SetAffectedLayer("ydkdrl");
                for (int i = ; i < SlotList.Count; i++)
                {
                    double HoleSize = ((int)(Math.Floor(((calc2.p2p_di(SlotList[i].ps, SlotList[i].pe) *  + SlotList[i].width)) * 0.5 / )) * );
                    SlotList[i] = calc2.l_extend(SlotList[i], (SlotList[i].width - HoleSize) * 0.001);
                    addCOM.pad(SlotList[i].ps, HoleSize);
                    addCOM.pad(SlotList[i].pe, HoleSize);
                }
                g.SetAffectedLayer("");
            }
            #endregion

2.线拉伸函数(关键在于此函数实现)

 /// <summary>
        /// 线Line拉伸
        /// </summary>
        /// <param name="l"></param>
        /// <param name="extend_val">拉伸数值</param>
        /// <param name="type_">0两端拉伸  1起点拉伸  2端点拉伸</param>
        /// <returns></returns>
        public gL l_extend(gL l, double extend_val, byte type_ = )
        {
            gL tempL = l;
            double angle_ = p_ang(l.ps, l.pe);
            if (type_ == )
            {
                tempL.ps = p_val_ang(l.ps, extend_val, p_ang_invert(angle_));
            }
            else if (type_ == )
            {
                tempL.pe = p_val_ang(l.pe, extend_val, angle_);
            }
            else
            {
                extend_val = extend_val * 0.5;
                tempL.ps = p_val_ang(l.ps, extend_val, p_ang_invert(angle_));
                tempL.pe = p_val_ang(l.pe, extend_val, angle_);
            }
            return tempL;
        }

         /// <summary>
        /// 求方位角
        /// </summary>
        /// <param name="ps"></param>
        /// <param name="pe"></param>
        /// <returns></returns>
        public double p_ang(gPoint ps, gPoint pe)
        {
            double a_ang = Math.Atan((pe.y - ps.y) / (pe.x - ps.x)) / Math.PI * ;
            //象限角  转方位角   计算所属象限   并求得方位角
            if (pe.x >= ps.x && pe.y >= ps.y)  //↗    第一象限
            {
                return a_ang;
            }
            else if (!(pe.x >= ps.x) && pe.y >= ps.y)  // ↖   第二象限
            {
                return a_ang + ;
            }
            else if (!(pe.x >= ps.x) && !(pe.y >= ps.y))  //↙   第三象限
            {
                return a_ang + ;
            }
            else if (pe.x >= ps.x && !(pe.y >= ps.y))  // ↘   第四象限
            {
                return a_ang + ;
            }
            else
            {
                return a_ang;
            }
        }

        /// <summary>
        /// 求反方位角
        /// </summary>
        /// <param name="ang_direction"></param>
        /// <returns></returns>
        public double p_ang_invert(double ang_direction)//求反方位角
        {
            if (ang_direction >= )
                return ang_direction - ;
            else
                return ang_direction + ;
        }
        /// <summary>
        /// 求增量坐标
        /// </summary>
        /// <param name="ps">起点</param>
        /// <param name="val">增量值</param>
        /// <param name="ang_direction">角度</param>
        /// <returns></returns>
        public gPoint p_val_ang(gPoint ps, double val, double ang_direction)
        {
            gPoint pe;
            pe.x = ps.x + val * Math.Cos(ang_direction * Math.PI / );
            pe.y = ps.y + val * Math.Sin(ang_direction * Math.PI / );
            return pe;
        }

3.点线数据结构

    /// <summary>
    /// 点  数据类型 (XY)
    /// </summary>
    public struct gPoint
    {
        public gPoint(gPoint p_)
        {
            this.x = p_.x;
            this.y = p_.y;
        }
        public gPoint(double x_val, double y_val)
        {
            this.x = x_val;
            this.y = y_val;
        }
        public double x;
        public double y;
        public static gPoint operator +(gPoint p1, gPoint p2)
        {
            p1.x += p2.x;
            p1.y += p2.y;
            return p1;
        }
        public static gPoint operator -(gPoint p1, gPoint p2)
        {
            p1.x -= p2.x;
            p1.y -= p2.y;
            return p1;
        }

    }
     /// <summary>
    /// Line 数据类型
    /// </summary>
    public struct gL
    {
        public gL(double ps_x, double ps_y, double pe_x, double pe_y, double width_)
        {
            this.ps = new gPoint(ps_x, ps_y);
            this.pe = new gPoint(pe_x, pe_y);
            this.negative = false;
            this.symbols = "r";
            this.attribut = string.Empty;
            this.width = width_;
        }
        public gL(gPoint ps_, gPoint pe_, double width_)
        {
            this.ps = ps_;
            this.pe = pe_;
            this.negative = false;
            this.symbols = "r";
            this.attribut = string.Empty;
            this.width = width_;
        }
        public gL(gPoint ps_, gPoint pe_, string symbols_, double width_)
        {
            this.ps = ps_;
            this.pe = pe_;
            this.negative = false;
            this.symbols = symbols_;
            this.attribut = string.Empty;
            this.width = width_;
        }
        public gPoint ps;
        public gPoint pe;
        public bool negative;//polarity-- positive  negative
        public string symbols;
        public string attribut;
        public double width;
        public static gL operator +(gL l1, gPoint move_p)
        {
            l1.ps += move_p;
            l1.pe += move_p;
            return l1;
        }

五.加短槽引孔脚本UI

六.加短槽效果