Other earlier systems installed in closed-circuit continuous-flow tunnels alleviated the need for generating store trajectories in the brief time frame dictated by blowdown tunnels. By using a digital computer to generate trajectories, the initial system setup and checkout times were greatly shortened and electronic drifts were virtually eliminated.

The digital computer, using the balance forces and moments in conjunction with the equation of motion, would output store model coordinates and attitude for the next point on the trajectory to some peripheral device that generated hard copy. An operator seated at this output device would then manually position the store model to these coordinates. The disadvantage of this method was its extreme slowness since the operation was open looped. 

Most of the early captive trajectory testing development effort was performed at the David Taylor Model Basin, Chance Vought Corporation, the Convair Division of General Dynamics, and the Cornell Aeronautical Laboratories.

另外一些早期配备在闭回路连续式风洞中的装置，不像在下吹式风洞情况下那样，要求在很短的时间内生成外挂轨迹。利用数字计算机生成轨迹的方法，大大缩短了装置的初始准备与检查时间，并实际消除了电子漂移现象。

利用天平测得的力与力矩连同外挂运动方程，数字电子计算机可将轨迹上下一个点的外挂模型座标及姿态作为输出量，输给某个可产生硬拷贝的外围设备。随后，坐在这台输出设备旁的操作员就用手工把外挂模型移动到这些座标上。这种方法的缺点是速度极其缓慢，因为采用的是开环式的操作。

初期的捕获轨迹试验研究工作，大部分是在查恩斯·沃特公司大卫·泰勒模型试验池、通用动力公司康维尔分部以及柯内尔航空实验室等处进行的。

In 1967, the captive trajectory system shown in Figure 1 was installed in the Propulsion Wind Tunnel (PWT) Facility at the AEDC. This system, which is still operational, is a closed-loop six-degree-of-freedom system utilizing a digital computer to solve the equations of motion and to position the store model. This system uses a position-based control technique that initially positions store model to the carriage position, reads the forces and moments acting on the store model, combines these forces and moments with the initial conditions to provide input parameters to the store model equations of motion, and then solves these equations and integrates to obtain the coordinates of the next point on the trajectory. "The store model is then moved to this set of coordinates and allowed to remain there while data are taken that can be used in conjunction with those previously obtained to determine succeeding points on the trajectory.

In 1975 another captive trajectory system was made operational in the von Kármán Gas Dynamics Facility (VKF) at the AEDC. The operation of this system is very similar to that used in the PWT.

1967年，图1(此略）上所示的捕获轨迹试验装置安装到AEDC推进风洞（PWT)设备中。这个装置现在仍可工作，是一个利用数字计算机求解运动方程并将外挂模型定位的闭环六自由度系统。该装置利用速过位置进行控制的技术，具体做法是：一开始，将外挂模型置于挂架位置上，读取作用于外挂模型上的力与力矩数据，将这些力与力矩数据与初始条件结合起来，给出外挂模型运动方程组的输入参数；然后，求解运动方程组并进行积分，获得轨迹上下一点的座标值。此后，将外挂模型移动到这一组座标设定的位置上，并使其停留在那里，同时测取部件可与前面获得的数据配套使用的数据，来决定轨迹上的后面各点。

1975年，另一台捕获轨迹装置在AEDC冯·卡门气体动力学设备（VKF）上投入使用。这台装置的工作原理与PWT上部一台的非常相似。

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