课程:MA6501 Manufacturing Automation and Control(制造自动化与控制) 学校:Nanyang Technological University(南洋理工大学) 来源 PDF:
- MA6501 2023-2024 Semester 1.pdf(8 页,4 大题)
- MA6501 2024-2025 Semester 1.pdf(8 页,4 大题)
- MA6501 2025-2026 Semester 1.pdf(16 页,4 大题,总分 100) 考试形式:3 小时 · OPEN-BOOK · 所有题目均必答
一、三年试卷整体对比(Year-by-Year Overview)
| 维度 / Dimension | 2023-2024 | 2024-2025 | 2025-2026 |
|---|---|---|---|
| 题量 / Questions | 4 大题 / 4 major questions | 4 大题 / 4 major questions | 4 大题(每题 25 分) / 4 major questions (25 marks each) |
| 页数 / Pages | 7 页 / 7 pages | 7 页 / 7 pages | 15 页 / 15 pages |
| 机构分析 / Mobility | 空间机构 2 个(果实采摘 + 7 构件机械臂) / 2 spatial mechanisms (fruit picking + 7-link arm) | 空间机构 2 个(织机挂钩 + 送针机构) / 2 spatial mechanisms (loom hook + needle-feeding mechanism) | 平行机构 2 个(5-bar + 4-bar) / 2 parallel mechanisms (5-bar + 4-bar) |
| 机器人运动学 / Kinematics | 3-DOF RRP + 逆解 / 3-DOF RRP + inverse kinematics | 4-DOF P3R + $A_2^0 = A_1^0 A_2^1$ 展开 / 4-DOF P3R + expansion of $A_2^0 = A_1^0 A_2^1$ | 7-DOF 双臂机器人 · DH 参数 + 正解 / 7-DOF dual-arm robot, DH parameters + forward kinematics |
| 案例题 / Case Study | 机上餐车装配(Picking/Assembly/Loading) / onboard meal-cart assembly (picking / assembly / loading) | 飞机机翼铣削(移动 + 末端切削) / aircraft wing milling (mobile base + end-effector cutting) | 机场/邮轮行李搬运(自主移动 + 25 kg 上下载) / airport or cruise luggage handling (autonomous mobility + 25 kg loading/unloading) |
| 电路 / Circuit | 电桥 + 双运放 $\to V_2(\delta)$ / bridge + two op-amps $\to V_2(\delta)$ | 电桥 + 单运放 $\to V_{out}(\delta)$ + 工作台 $\tau \to x$ 传递函数 / bridge + single op-amp $\to V_{out}(\delta)$ + worktable transfer function $\tau \to x$ | $V_i \to V_o$ 含 $C, L, R, R_F$ 的频率响应 + $G_p(s)$ 闭环设计 / frequency response of $V_i \to V_o$ with $C, L, R, R_F$ + closed-loop design for $G_p(s)$ |
| 控制系统 / Control | $H(s)$ 滤波类型 + 闭环 $C(s)/R(s)$ / filter type of $H(s)$ + closed-loop $C(s)/R(s)$ | PI 控制器 $1/(s^2+0.5s+1)$ 峰值时间 / peak time of a PI-controlled $1/(s^2+0.5s+1)$ system | PI 控制器:peak time 1.5 s,超调 5%,求 $k_1, k_2$ / PI controller: peak time 1.5 s, 5% overshoot, solve for $k_1, k_2$ |
| 生产线 / Production Line | 20 h $\times$ 0.2% $\times$ 1.5 h,$\eta=90\%$ / 20 h $\times$ 0.2% $\times$ 1.5 h, $\eta=90\%$ | 35 h $\times$ 0.01% $\times$ 2 h,$\eta=95\%$ / 35 h $\times$ 0.01% $\times$ 2 h, $\eta=95\%$ | 10 h $\times$ 0.05% $\times$ 0.5 h,$\eta=98\%$ / 10 h $\times$ 0.05% $\times$ 0.5 h, $\eta=98\%$ |
| 视觉 / Vision | 1024$\times$1024,$\Delta u/\Delta v$ 不同,求传送带速度 / 1024$\times$1024, unequal $\Delta u/\Delta v$, find the conveyor speed | 2048$\times$2048,$\Delta u/\Delta v$ 不同,求速度 / 2048$\times$2048, unequal $\Delta u/\Delta v$, find the speed | 2048$\times$2048,求两点 A/B 真实距离 / 2048$\times$2048, find the real distance between points A and B |
结论 / Takeaway: 三年考纲高度稳定:Kutzbach 机构自由度 $\to$ DH 参数正逆解 $\to$ 电桥/运放电路 $\to$ 反馈控制闭环 $\to$ 生产线效率 $\to$ 机器视觉像素/世界坐标换算。每年只更换图形、数据和机器人构型,解题套路完全可复用。
The exam structure is highly stable across all three years: Kutzbach mobility $\to$ DH-based forward and inverse kinematics $\to$ bridge and op-amp circuits $\to$ closed-loop feedback control $\to$ production-line efficiency $\to$ pixel-to-world conversion in machine vision. Each year mainly changes the figures, data, and robot configuration, so the solution workflow is largely reusable.
二、2023-2024 学年真题(Q1–Q4 摘要 / 2023-2024 Exam Summary)
Q1 · 机构 + 机上餐车装配案例 / Mechanisms + Meal-Cart Assembly Case
- (a) 10 分:对果实采摘装置、7 构件多自由度机械臂分别用 Kutzbach 空间式 $M = 6(n-1) - \sum(6-f_i)$ 求自由度。
- (b) 机上餐车自动化 5/6/4/5 分:
- (1) Robot A / Robot B 机械臂类型与理由(载荷 2 kg vs 20 kg)
- (2) Robot A 末端执行器(罐装饮料 / 玻璃酒瓶 / 薯片)+ 附加传感器
- (3) Robot B 末端执行器(整盘 20 kg 装进 Cart)+ 装载传感器
- (4) Robot A/B 相机方案(视场与物体类型)
English summary
- (a) 10 marks: Use the spatial Kutzbach equation $M = 6(n-1) - \sum(6-f_i)$ to compute the DOF of the fruit-picking mechanism and the 7-link multi-DOF manipulator.
- (b) Meal-cart automation case study (5/6/4/5 marks):
- (1) Select the arm type for Robot A and Robot B and justify the choice (2 kg vs 20 kg payload).
- (2) Propose Robot A end-effectors for canned drinks, glass bottles, and chips, plus any extra sensors.
- (3) Propose Robot B’s end-effector for loading a full 20 kg tray into the cart, plus loading sensors.
- (4) Propose the camera setup for Robot A and Robot B based on field of view and object characteristics.
Q2 · 3-DOF RRP 机器人运动学(共 20 分 / 20 marks)
- $z_1 \perp z_0$ 带正偏置 $e$;$z_1, z_2$ 垂直相交;末端 Frame 3 沿 $z_2$ 距离 $d$。
- (a) 8 分:DH 参数表(Appendix A)
- (b) 6 分:$A_1^0, A_2^1, A_3^2$ 及正运动学 $A_3^0 = A_1^0 \cdot A_2^1 \cdot A_3^2$
- (c) 6 分:已知末端原点 $[b_1, b_2, b_3]^T$,求逆解 $\theta_1, \theta_2, d$
English summary
- $z_1 \perp z_0$ with a positive offset $e$; $z_1$ and $z_2$ intersect orthogonally; the end-effector frame 3 is located a distance $d$ along $z_2$.
- (a) 8 marks: fill in the DH parameter table (Appendix A).
- (b) 6 marks: write $A_1^0, A_2^1, A_3^2$ and the forward kinematics $A_3^0 = A_1^0 \cdot A_2^1 \cdot A_3^2$.
- (c) 6 marks: given the end-point coordinates $[b_1, b_2, b_3]^T$, solve the inverse kinematics for $\theta_1, \theta_2, d$.
Q3 · 电桥/运放 + 闭环控制 / Bridge, Op-Amp, and Closed-Loop Control
- (a) 电桥接运放 A1、再接 A2,求 $V_2 = f(\delta, R_2, V_1, R)$(12 分);当 $R=100\Omega, V_1=15\text{V}, R_2=1\text{k}\Omega$ 求 $V_2(\delta)$(3 分)
- (b) $K_p=5$,$G(s)=1/(s+3)$,滤波器 $H(s) = (s^2+(100\pi)^2)/(s^2+400\pi s+(100\pi)^2)$
- (i) $\omega \to 0$, $\omega=100\pi$, $\omega \to \infty$ 三点频响,判定滤波类型,通带最大增益 dB(8 分)
- (ii) 闭环 $C(s)/R(s)$(2 分)
English summary
- (a) A bridge circuit feeds op-amp A1 and then A2. Derive $V_2 = f(\delta, R_2, V_1, R)$ (12 marks). Then substitute $R=100\Omega$, $V_1=15\text{V}$, and $R_2=1\text{k}\Omega$ to obtain $V_2(\delta)$ (3 marks).
- (b) Given $K_p=5$, $G(s)=1/(s+3)$, and $H(s) = (s^2+(100\pi)^2)/(s^2+400\pi s+(100\pi)^2)$:
- (i) Evaluate the frequency response at $\omega \to 0$, $\omega=100\pi$, and $\omega \to \infty$, identify the filter type, and state the maximum passband gain in dB (8 marks).
- (ii) Derive the closed-loop transfer function $C(s)/R(s)$ (2 marks).
Q4 · 生产线 + PI + 视觉 / Production Line, PI, and Vision
- (a) 10 分:$T_c=20\text{h}$,$F=0.2$/机器人,$T_d=1.5\text{h}$,$\eta=90$,求机器人台数
- (b) 5 分:$G(s)=13/(s^2+7s+13)$ 的最大超调
- (c) 10 分:图像分辨率 1024$\times$1024,$O_c$ 到 $O$ 距离 5 cm,$O$ 像素坐标 $(511, 511)$,$\Delta u=0.001\text{cm}$,$\Delta v=0.002\text{cm}$;$t_1$ $(50, 700) \to t_2 = t_1+5$ $(625, 700)$ 求传送带速度
English summary
- (a) 10 marks: with $T_c=20\text{h}$, $F=0.2\%$ per robot, $T_d=1.5\text{h}$, and $\eta=90\%$, compute the required number of robots.
- (b) 5 marks: find the maximum overshoot of $G(s)=13/(s^2+7s+13)$.
- (c) 10 marks: an image has resolution 1024$\times$1024, the distance from $O_c$ to $O$ is 5 cm, the pixel coordinate of $O$ is $(511, 511)$, and $\Delta u=0.001\text{cm}$, $\Delta v=0.002\text{cm}$. From $t_1$ point $(50, 700)$ to $t_2=t_1+5\text{s}$ point $(625, 700)$, compute the conveyor speed.
三、2024-2025 学年真题 / 2024-2025 Exam Summary
Q1 · 空间机构 + 机翼铣削案例 / Spatial Mechanisms + Wing-Milling Case
- (a) 10 分:织机挂钩机构 + 送针机构 Kutzbach 自由度
- (b) 机翼铣削 5×4 分:
- (1) 机械臂类型(50 N 法向力 · 亚毫米精度 · 端铣 10 mm/s)
- (2) 力传感器选型(铣削/钻孔)
- (3) 工件对齐视觉系统
- (4) 承载 5 吨的移动底盘结构
- (5) 工厂室内导航 + 高精度定位传感器
English summary
- (a) 10 marks: compute the Kutzbach mobility for the loom-hook mechanism and the needle-feeding mechanism.
- (b) Wing-milling case study (5 parts, 4 marks each):
- (1) Select a manipulator for 50 N normal force, sub-millimeter accuracy, and end milling at 10 mm/s.
- (2) Choose the force sensor type for milling or drilling.
- (3) Propose a vision system for workpiece alignment.
- (4) Propose a mobile platform capable of carrying 5 tons.
- (5) Propose indoor factory navigation and high-accuracy localization sensors.
Q2 · 4-DOF P3R 运动学(20 分 / 20 marks)
- $z_0$(移动)与 $z_1$(回转)相交,扭转角 $\alpha_1$;$z_1, z_2$ 既不平行也不相交,扭转角 $\alpha_2$;$z_2 \parallel z_3$,偏移 $d_3$;末端 $z_4$ 沿 $x_3$ 距离 $a_4$。
- (a) 8 分 DH 参数;(b) 8 分 $A_1^0 \sim A_4^3$;(c) 4 分 展开 $A_2^0 = A_1^0 A_2^1$
English summary
- $z_0$ (prismatic axis) intersects $z_1$ (revolute axis) with twist angle $\alpha_1$; $z_1$ and $z_2$ are skew with twist angle $\alpha_2$; $z_2 \parallel z_3$ with offset $d_3$; the end-effector axis $z_4$ is located a distance $a_4$ along $x_3$.
- (a) 8 marks: complete the DH table.
- (b) 8 marks: derive $A_1^0$ through $A_4^3$.
- (c) 4 marks: expand $A_2^0 = A_1^0 A_2^1$.
Q3 · 电桥/运放 + 工作台机电模型 / Bridge, Op-Amp, and Electromechanical Table Model
- (a) $R_s = R(1+\delta)$,单运放输出 $V_{out} = f(V, \delta)$(13+2 分)
- (b) 电机 $\to$ 齿轮 $\to$ 齿条 $\to$ 质量 $M$(弹簧 $k$,阻尼 $c$)
- (i) $\tau(t) \to x(t)$ 微分方程(5 分)
- (ii) $X(s)/T(s)$ 传递函数(5 分)
English summary
- (a) With $R_s = R(1+\delta)$, derive the single-op-amp output $V_{out} = f(V, \delta)$ (13+2 marks).
- (b) For the motor $\to$ gear $\to$ rack $\to$ mass $M$ system with spring $k$ and damper $c$:
- (i) derive the differential equation from $\tau(t)$ to $x(t)$ (5 marks),
- (ii) derive the transfer function $X(s)/T(s)$ (5 marks).
Q4 · 生产线 + 视觉 / Production Line and Vision
- (a) $T_c=35\text{h}$, $F=0.01$, $T_d=2\text{h}$, $\eta=95$
- (b) $G(s)=1/(s^2+0.5s+1)$ 峰值时间
- (c) 2048$\times$2048,$O \to O_c = 6\text{cm}$,$O_w$ 原点 $(20, 20, -150)\text{cm}$,$\Delta u=0.0012$, $\Delta v=0.0013\text{cm}$,$(200, 1200) \to (2000, 1200)$ 10 s,求速度
English summary
- (a) Compute the required number of robots using $T_c=35\text{h}$, $F=0.01\%$, $T_d=2\text{h}$, and $\eta=95\%$.
- (b) Find the peak time of $G(s)=1/(s^2+0.5s+1)$.
- (c) For a 2048$\times$2048 image with $O \to O_c = 6\text{cm}$, world origin $O_w=(20, 20, -150)\text{cm}$, $\Delta u=0.0012$, $\Delta v=0.0013\text{cm}$, and pixel motion $(200, 1200) \to (2000, 1200)$ over 10 s, compute the conveyor speed.
四、2025-2026 学年真题(最新,分值明确 / Latest Paper with Explicit Marks)
Q1 · 平行机构 + 工作空间 + 行李搬运案例(25 分 / 25 marks)
- (a) 6 分:5-bar (S-S-S-R-C) 和 4-bar (R-B-C-P) 平行机构 Kutzbach
- (b) 4 分:3-DOF 机器人工作空间绘图(base $270^\circ$,arm $360^\circ$,升降 $d$)
- (c) 15 分:行李搬运系统设计(25 kg,室内外导航,1 m/s 安全上限,电梯联动)
- (i) 机械臂类型(4 分)
- (ii) 移动底盘类型(4 分)
- (iii) 装载/卸载 + 导航传感器(4 分)
- (iv) 其他考虑(3 分)
English summary
- (a) 6 marks: apply the Kutzbach formula to the 5-bar (S-S-S-R-C) and 4-bar (R-B-C-P) parallel mechanisms.
- (b) 4 marks: draw the workspace of the 3-DOF robot with base rotation $270^\circ$, arm rotation $360^\circ$, and lift distance $d$.
- (c) 15 marks: design a baggage-handling system for 25 kg luggage with indoor/outdoor navigation, a safe speed limit of 1 m/s, and elevator coordination:
- (i) manipulator type (4 marks),
- (ii) mobile base type (4 marks),
- (iii) loading/unloading and navigation sensors (4 marks),
- (iv) additional considerations (3 marks).
Q2 · 双臂 7-DOF 机器人 DH(25 分 / 25 marks)
- 躯干 $z_0$、肩 $z_1$ 相交于 $W$,夹角 $\alpha$;$z_1 \perp z_2$ 相交于 $S$,$W$-$S = d_0$;$z_2 \parallel z_3 \parallel z_4$,间距 $d_1, d_2$;$z_4 \perp z_5$ 相交,$z_5 \perp z_6$ 相交,间距 $d_3$;末端 $e$ 沿 $z_6$ 偏移 $l_1$。
- (a) 7 分:在图上标出 frame 1-6 的 x 轴
- (b) 8 分:填表 $\theta_i / d_i / \alpha_i / a_i$
- (c) 10 分:$A_1^0, \ldots, A_6^5$ 和正运动学 $A_e^0 = A_1^0 \cdot A_2^1 \cdots A_e^6$(无需展开矩阵乘法)
English summary
- The torso axis $z_0$ and shoulder axis $z_1$ intersect at $W$ with angle $\alpha$; $z_1 \perp z_2$ intersect at $S$ with $W$-$S = d_0$; $z_2 \parallel z_3 \parallel z_4$ with spacings $d_1, d_2$; $z_4 \perp z_5$ intersect, $z_5 \perp z_6$ intersect with spacing $d_3$; the end-point $e$ is offset by $l_1$ along $z_6$.
- (a) 7 marks: draw the x-axes of frames 1-6 on the figure.
- (b) 8 marks: fill in the DH table $\theta_i / d_i / \alpha_i / a_i$.
- (c) 10 marks: write $A_1^0, \ldots, A_6^5$ and the forward kinematics $A_e^0 = A_1^0 \cdot A_2^1 \cdots A_e^6$ without expanding the full matrix product.
Q3 · 运放电路 + $K_v$ 与闭环极点设计(25 分 / 25 marks)
- (a) 倒相放大电路 $V_i$—$C$—$L$—$R$—(-输入);$R_F=1000\Omega$, $R=100\Omega$, $C=20\mu\text{F}$, $L=2\text{mH}$
- (i) 5 分:$H(j\omega) = V_o / V_i$
- (ii) 8 分:最大增益与对应频率
- (b) $G_p(s) = 100 / [s(s^2+10s+100)]$;目标 $G_{cl} = K / [(s^2+20s+200)(s+a)]$
- (i) 8 分:要求速度误差常数 $K_v=8$,求 $K$ 和 $a$
- (ii) 4 分:求控制器 $G_c(s)$
English summary
- (a) For the inverting amplifier $V_i$-$C$-$L$-$R$-(- input) with $R_F=1000\Omega$, $R=100\Omega$, $C=20\mu\text{F}$, and $L=2\text{mH}$:
- (i) derive $H(j\omega) = V_o / V_i$ (5 marks),
- (ii) find the maximum gain and the corresponding frequency (8 marks).
- (b) Given $G_p(s) = 100 / [s(s^2+10s+100)]$ and target closed-loop transfer $G_{cl} = K / [(s^2+20s+200)(s+a)]$:
- (i) 8 marks: with velocity error constant $K_v=8$, solve for $K$ and $a$,
- (ii) 4 marks: derive the controller $G_c(s)$.
Q4 · 生产线效率 + PI 设计 + 视觉测距(25 分 / 25 marks)
- (a) 10 分:PI 控制 $A(s) = k_1 + k_2/s$,被控 $B(s) = 1/(s+10)$,要求 peak time $t_p=1.5\text{s}$,超调 $M_p=5$,求 $k_1, k_2$
- (b) 10 分:2048$\times$2048,$O \to O_c = 5\text{cm}$,$O_w$ 原点 $(50, 50, -100)\text{cm}$,$\Delta u=0.0002$, $\Delta v=0.0003\text{cm}$;点 A $(500, 800)$,B $(1800, 1200)$,求 AB 实际距离
- (c) 5 分:$T_c=10\text{h}$,$F=0.05$,$T_d=0.5\text{h}$,$\eta=98$,求最少机器人数
English summary
- (a) 10 marks: for PI controller $A(s) = k_1 + k_2/s$ and plant $B(s) = 1/(s+10)$, with required peak time $t_p=1.5\text{s}$ and overshoot $M_p=5\%$, solve for $k_1, k_2$.
- (b) 10 marks: with a 2048$\times$2048 image, $O \to O_c = 5\text{cm}$, world origin $(50, 50, -100)\text{cm}$, $\Delta u=0.0002$, $\Delta v=0.0003\text{cm}$, and points A $(500, 800)$, B $(1800, 1200)$, compute the real-world distance AB.
- (c) 5 marks: with $T_c=10\text{h}$, $F=0.05\%$, $T_d=0.5\text{h}$, and $\eta=98\%$, compute the minimum number of robots.
五、核心知识点与公式(Core Knowledge & Formulas)
1. Kutzbach 机构自由度(Mobility)
空间机构 / Spatial
$$M = 6(n-1) - \sum_{i=1}^{j} (6 - f_i)$$平面机构 / Planar
$$M = 3(n-1) - \sum_{i=1}^{j} (3 - f_i)$$| 运动副 / Joint | 符号 / Symbol | DOF $f$ |
|---|---|---|
| Revolute 转动副 / revolute joint | R | 1 |
| Prismatic 移动副 / prismatic joint | P | 1 |
| Cylindrical 圆柱副 / cylindrical joint | C | 2 |
| Ball 球副 / ball joint | B | 2 |
| Spherical 球铰 / spherical joint | S | 3 |
注意 / Note:试卷 2023 把 $C$=2-DOF cylindrical,$S$=3-DOF ball;2024 也是 $C=2, S=3$;2025 特别定义 $B$=2-DOF, $S$=3-DOF,务必看题目定义。
In the 2023 paper, $C$ is a 2-DOF cylindrical joint and $S$ is a 3-DOF ball joint; the 2024 paper uses the same convention. The 2025 paper explicitly defines $B$ as 2 DOF and $S$ as 3 DOF, so always follow the definition given in the question.
2. Denavit-Hartenberg 参数与变换矩阵(DH Parameters and Transform Matrix)
四参数 / Four parameters(标准 DH, Distal convention):
- $\theta_i$:关节角(绕 $z_{i-1}$) / joint angle about $z_{i-1}$
- $d_i$:关节偏移(沿 $z_{i-1}$) / joint offset along $z_{i-1}$
- $\alpha_i$:连杆扭转(绕 $x_i$) / link twist about $x_i$
- $a_i$:连杆长度(沿 $x_i$) / link length along $x_i$
齐次变换矩阵 / Homogeneous transform
$$A_i^{i-1} = \begin{bmatrix} c\theta_i & -s\theta_i c\alpha_i & s\theta_i s\alpha_i & a_i c\theta_i \\ s\theta_i & c\theta_i c\alpha_i & -c\theta_i s\alpha_i & a_i s\theta_i \\ 0 & s\alpha_i & c\alpha_i & d_i \\ 0 & 0 & 0 & 1 \end{bmatrix}$$正运动学 / Forward kinematics:$T_n^0 = A_1^0 \cdot A_2^1 \cdots A_n^{n-1}$
3. 电桥 + 运放(Bridge + Op-amp)
反相放大 / Inverting:$V_{out} = -(R_f / R_{in}) \cdot V_{in}$
同相放大 / Non-inverting:$V_{out} = (1 + R_f / R_{in}) \cdot V_{in}$
差分放大输入桥电压 / Bridge unbalance:
$$V_{bridge} \approx \frac{V_1 \cdot \delta}{4}\quad (\delta \ll 1)$$整体级联后(2023 Q3a)最终形式 / Overall cascaded result for 2023 Q3a:
$$V_2 = -\frac{R_2}{R}\cdot\frac{\delta}{2(2+\delta)}\cdot V_1 \approx -\frac{R_2 V_1 \delta}{4R}$$代入 $R=100, R_2=1\text{k}\Omega, V_1=15\text{V}$,得 $V_2 \approx -37.5\delta$ (V)。
Substituting $R=100$, $R_2=1\text{k}\Omega$, and $V_1=15\text{V}$ gives $V_2 \approx -37.5\delta$ (V).
4. 二阶系统性能指标(Second-Order Performance Metrics)
对标准式 / For the standard form
$$G(s) = \omega_n^2 / (s^2 + 2\zeta\omega_n s + \omega_n^2)$$| 指标 / Metric | 公式 / Formula |
|---|---|
| 阻尼比 $\zeta$ / damping ratio | $2\zeta\omega_n = $ 线性项系数 / coefficient of the first-order term |
| 固有频率 $\omega_n$ / natural frequency | $\omega_n^2 = $ 常数项 / constant term |
| 峰值时间 $t_p$ / peak time | $\pi / (\omega_n \sqrt{1-\zeta^2})$ |
| 最大超调 $M_p$ / maximum overshoot | $\exp(-\zeta\pi / \sqrt{1-\zeta^2}) \times 100$ |
| 上升时间 $t_r$ / rise time | $(\pi - \arctan(\sqrt{1-\zeta^2}/\zeta)) / (\omega_n \sqrt{1-\zeta^2})$ |
| 调节时间 $t_s$ / settling time | $4 / (\zeta\omega_n)$(2% 准则 / 2% criterion) |
2025 Q4a / 2025 Q4a:$t_p=1.5 \Rightarrow \omega_d = \pi/1.5 \approx 2.094$;$M_p=5 \Rightarrow \zeta \approx 0.690$;由此反推闭环特征方程 $s^2 + 2\zeta\omega_n s + \omega_n^2 = 0$,与 PI 开环 $A \cdot B / (1 + AB)$ 匹配求 $k_1, k_2$。
Use $t_p=1.5$ to get $\omega_d = \pi/1.5 \approx 2.094$ and $M_p=5\%$ to get $\zeta \approx 0.690$. Then match the desired characteristic equation $s^2 + 2\zeta\omega_n s + \omega_n^2 = 0$ against the PI closed-loop form to solve for $k_1$ and $k_2$.
5. 生产线效率与机器人数(Production Line Efficiency)
Groover 公式 / Groover formula:
$$R_p = \frac{R_c}{1 + F \cdot T_d \cdot R_c}, \quad \eta = \frac{T_c}{T_c + n F T_d}$$另一常用等价式(考试常用,按“每机器人故障”计) / Another common equivalent form used in exams:
$$\eta = \frac{T_c}{T_c + n \cdot F \cdot T_d}$$求 $n$ / Solve for $n$:$n = T_c \cdot (1-\eta) / (\eta \cdot F \cdot T_d)$
| 年份 / Year | $T_c$ (h) | $F$ | $T_d$ (h) | $\eta$ | 解算 $n$ / Computed $n$ |
|---|---|---|---|---|---|
| 2023 | 20 | 0.002 | 1.5 | 0.90 | $20 \cdot 0.10 / (0.90 \cdot 0.002 \cdot 1.5) \approx$ 740.7,取 741 / round up to 741 |
| 2024 | 35 | 0.0001 | 2.0 | 0.95 | $35 \cdot 0.05 / (0.95 \cdot 0.0001 \cdot 2.0) \approx$ 9210.5,取 9211 / round up to 9211 |
| 2025 | 10 | 0.0005 | 0.5 | 0.98 | $10 \cdot 0.02 / (0.98 \cdot 0.0005 \cdot 0.5) \approx$ 816.3,取 817 / round up to 817 |
结果取向上取整(机器人台数必须是整数)。若题目用 $R_p = R_c / (1 + F T_d R_c)$ 版本,计算步骤略有差异,两种都写以展示推导。
Always round upward because the number of robots must be an integer. If the paper uses the $R_p = R_c / (1 + F T_d R_c)$ version, the intermediate steps differ slightly; it is safer to write both forms to show your derivation.
6. 机器视觉坐标换算(Vision: Pixel $\leftrightarrow$ World)
像素 $\to$ 成像平面 / Pixel to image plane:
$$x = (u - u_0) \cdot \Delta u, \quad y = (v - v_0) \cdot \Delta v$$成像平面 $\to$ 世界(针孔模型) / Image plane to world coordinates (pinhole model):
$$X_w = x \cdot \frac{Z_c}{f}, \quad Y_w = y \cdot \frac{Z_c}{f}$$当像面平行于 workspace 且题目给 $O \to O_c = h$:可视为放大比 $M = h / $ 焦距,但考试多直接按“像平面在工件表面比例尺”处理,即:
$$\Delta X_w = \Delta u \cdot (u_2 - u_1) \cdot \frac{Z_c}{f}$$若像面与物面平行且垂直距离为 $h$(如 2024/2025 的 $\Delta u, \Delta v$ 已折算到像元物理尺寸),则常用简化:
$$\text{真实距离} = \sqrt{(\Delta u \cdot \Delta n_u)^2 + (\Delta v \cdot \Delta n_v)^2} \times \frac{Z_w}{h}$$If the image plane is parallel to the workspace and the paper gives $O \to O_c = h$, this is usually treated as a magnification problem. In many exam solutions, the pixel dimensions are already converted into physical image-plane distances, so the simplified scale-up relation above is the most practical one to use.
2025 Q4b 计算示例 / Worked example for 2025 Q4b(A $(500, 800)$, B $(1800, 1200)$):
- $\Delta n_u = 1800 - 500 = 1300$ 像素;$\Delta n_v = 1200 - 800 = 400$ 像素 / pixels
- 像平面距离 / image-plane distances:$dx = 1300 \cdot 0.0002 = 0.26$ cm,$dy = 400 \cdot 0.0003 = 0.12$ cm
- 放大比 / magnification:$M = |Z_w| / h = 100 / 5 = 20$
- 实际距离 / real distance $= \sqrt{0.26^2 + 0.12^2} \times 20 \approx \sqrt{0.0676 + 0.0144} \times 20 \approx 0.2864 \times 20 \approx$ 5.73 cm
2023 Q4c 传送带速度 / Conveyor speed for 2023 Q4c:
- $\Delta n_u = 625 - 50 = 575$ 像素($v$ 方向不动 / no motion in the $v$ direction)
- 像平面位移 / image-plane displacement $= 575 \cdot 0.001 = 0.575$ cm
- 放大比 / magnification $= |Z_w| / h = 120 / 5 = 24$,实际位移 / real displacement $= 0.575 \times 24 = 13.8$ cm
- 速度 / speed $= 13.8\text{cm} / 5\text{s} = $ 2.76 cm/s
六、机器人系统选型通用模板(Robotic System Design Checklist)
2023 餐车、2024 机翼铣削、2025 行李搬运均是同一思路的情景化。
The 2023 meal-cart problem, the 2024 wing-milling problem, and the 2025 baggage-handling problem all follow the same design logic.
A. 机械臂类型 / Manipulator Type
| 任务特征 / Task profile | 推荐构型 / Recommended type | 理由 / Why |
|---|---|---|
| 轻载 + 多姿态抓取 / Light payload + multi-orientation grasping | 6-DOF 关节式(Articulated / Vertical) | 灵活,工作空间大 / flexible with a large workspace |
| 重载 + 平移为主 / Heavy payload + mainly translational motion | SCARA 或 Gantry/Cartesian | 刚度高,z 向承载强 / high rigidity and strong vertical load capacity |
| 精密插装(垂直插入) / Precision insertion | SCARA | x-y 柔性 / z 向刚度 / compliant in x-y and stiff in z |
| 接触式加工(力控) / Contact machining with force control | 6-DOF + 力传感器 / 6-DOF + force sensor | 力反馈 + 姿态补偿 / force feedback with pose compensation |
| 大载荷(20 kg / 25 kg+) / Large payload (20 kg / 25 kg+) | 工业 6-DOF 重载型 / heavy-duty industrial 6-DOF arm | 动力学余量大 / more dynamic margin |
B. 移动底盘 / Mobile Base
| 需求 / Requirement | 选型 / Recommended base | 理由 / Why |
|---|---|---|
| 平坦地面 + 高机动 / Flat floor + high maneuverability | Mecanum / Omni-wheel | 全向,零回转半径 / omnidirectional with zero turning radius |
| 重载(5 ton) / Heavy load (5 tons) | 差速驱动 + 多轮承载 / differential drive + multi-wheel support | 刚性,驱动效率高 / rigid with high drive efficiency |
| 室内外混合 / Mixed indoor-outdoor use | 4 轮差速 + 悬挂 / 4-wheel differential with suspension | 通过性好 / better terrain adaptability |
C. 末端执行器 / End-Effector
| 物品 / Item | 末端 / End-effector | 附加传感 / Extra sensing |
|---|---|---|
| 罐装饮料 / Canned drink | 夹爪(平行 2 指)或真空吸盘 / parallel two-finger gripper or vacuum cup | 力/触觉 / force or tactile sensing |
| 玻璃酒瓶 / Glass bottle | 柔性自适应夹爪 + 橡胶衬 / compliant adaptive gripper with rubber lining | 力/滑觉 / force or slip sensing |
| 软包零食(薯片) / Soft snack bag | 真空吸盘(低负压) / low-vacuum suction cup | 压力传感 / pressure sensing |
| 20 kg 整盘 / Full 20 kg tray | 钩爪 + 拖拽机构 或叉车式 / hook and drag mechanism or fork-style tool | 负载/姿态 IMU / load sensing and pose IMU |
| 行李(25 kg) / Baggage (25 kg) | 双臂抱取 或叉举结构 / dual-arm hug grasp or fork-lift structure | 称重 + 触觉 / weighing and tactile sensing |
D. 传感器 / Sensors
- 视觉 / Vision:
- 大视场(Robot A pick bay)→ 全局 2D 相机 + 结构光/3D / wide field of view: global 2D camera plus structured light or 3D sensing
- 近距精细(Robot B 装入隔层)→ 局部手眼 RGB-D / close-range precision: local eye-in-hand RGB-D camera
- 工件对齐(机翼)→ 线激光轮廓仪 / 结构光 3D / workpiece alignment: laser profile scanner or structured-light 3D vision
- 力 / Force:末端 6 轴 F/T sensor(铣削/装配);关节力矩传感器 / 6-axis force-torque sensor at the end-effector plus joint torque sensing
- 导航 / Navigation:2D/3D LiDAR + IMU + 轮式里程,室内用 UWB / VSLAM,工厂用 激光反射板 / 磁条 / UWB 亚厘米定位 / 2D or 3D LiDAR with IMU and wheel odometry, using UWB or VSLAM indoors and reflectors, magnetic strips, or sub-centimeter UWB in factories
- 安全 / Safety:急停、碰撞检测、限速、安全激光雷达(人机共融) / emergency stop, collision detection, speed limiting, and safety LiDAR for human-robot collaboration
E. 相机与照明 / Camera and Lighting
- Robot A:广角 + 顶置结构光 → 识别物体类型与位姿 / wide-angle view with overhead structured light for object classification and pose estimation
- Robot B:手眼相机 + 环形光源 → 对齐槽位 / eye-in-hand camera with ring light for slot alignment
- 一般准则 / General rule:视场 ≥ 目标大小×2;分辨率取决于最小可识别特征;照明避免镜面反射。 / Field of view should be at least twice the target size; resolution depends on the smallest feature you must identify; avoid specular reflections in lighting.
七、电路与控制系统答题模板(Circuit and Control Answer Templates)
1. 电桥输出 + 运放推导(通用步骤 / General Procedure)
- 写出电桥两输出点电位 $V_A, V_B$(电阻分压) / write the two bridge-node voltages $V_A$ and $V_B$ using voltage division.
- 代入 $R_s = R(1+\delta)$,得 $V_B - V_A = V \cdot \delta / [2(2+\delta)] \approx V \cdot \delta / 4$ / substitute $R_s = R(1+\delta)$ to obtain the bridge imbalance.
- 判断运放接法(反相/同相/差分) / identify whether the op-amp stage is inverting, non-inverting, or differential.
- 乘上增益得到 $V_{out}$ / multiply by the stage gain to get $V_{out}$.
- 代入具体数值化简 / substitute the numerical values and simplify.
2. 滤波器类型判别(2023 Q3b-i / Filter Identification)
给定 / Given
$$H(s) = \frac{s^2 + (100\pi)^2}{s^2 + 400\pi s + (100\pi)^2}$$- $\omega \to 0$:$|H| = (100\pi)^2 / (100\pi)^2 = $ 1
- $\omega = 100\pi$:分子 $= 0$,$|H| = 0$(陷波点 / notch point)
- $\omega \to \infty$:$s^2$ 相消,$|H| \to 1$
结论 / Conclusion:Notch(带阻 / band-stop)滤波器,陷波中心 $\omega = 100\pi$ rad/s(即 50 Hz,抑制工频噪声 / suppressing line-frequency noise)。通带最大增益 $= 1$,即 0 dB。
3. 闭环传递函数(标准回路 / Standard Closed-Loop Form)
前向 / Forward path $F(s) = K_p \cdot G(s)$,反馈 / feedback path $H(s)$:
$$\frac{C(s)}{R(s)} = \frac{F(s)}{1+F(s)H(s)} = \frac{K_p G(s)}{1 + K_p G(s) H(s)}$$4. PI + 一阶对象设计(2025 Q4a / PI Design with a First-Order Plant)
开环 / Open loop $A(s) B(s) = (k_1 s + k_2) / [s(s+10)]$;闭环特征方程 / closed-loop characteristic equation:
$$s^2 + (10 + k_1) s + k_2 = 0$$对比 / Match against $s^2 + 2\zeta\omega_n s + \omega_n^2$:
- $\omega_n^2 = k_2$,$2\zeta\omega_n = 10 + k_1$
- 由 / From $t_p=1.5, M_p=5$ 得 / obtain $\zeta \approx 0.6901$,$\omega_n = \pi / (1.5 \cdot \sqrt{1-\zeta^2}) \approx 2.094 / 0.7238 \approx$ 2.893 rad/s
- 故 / Hence $k_2 = \omega_n^2 \approx 8.37$,$k_1 = 2\zeta\omega_n - 10 \approx 2 \cdot 0.6901 \cdot 2.893 - 10 \approx -6.01$
- 说明 / Interpretation:PI 中 $k_1$ 可能为负,意味着需要前置反向放大或按题目框图如实解释;考试时把推导与数值写清楚即可。 / A negative $k_1$ may imply a sign inversion or a specific feedback convention in the given block diagram. In the exam, clear derivation and correct numbers are enough.
5. $K_v$ 与极点配置(2025 Q3b / Velocity Constant and Pole Placement)
$G_p(s) = 100 / [s(s^2+10s+100)]$;$G_{cl} = K / [(s^2+20s+200)(s+a)]$;单位反馈下 / under unity feedback:
- 速度误差常数 / Velocity error constant:$K_v = \lim_{s \to 0} s \cdot G_{open}(s)$
- 由 / From $G_{cl} = G_{open} / (1 + G_{open})$ 反推 / back-solve $G_{open} = G_{cl} / (1 - G_{cl})$
- 最终得到含 $K, a$ 的表达式,取 $K_v=8$ 解出 $(K, a)$ / derive the expression involving $K$ and $a$, then solve it with $K_v=8$
- 再由 / Then use $G_c = G_{open} / G_p$ 得到控制器形式(超前-滞后 / PID) / to obtain the controller form
八、复习建议(Revision Tips)
- 机构题必拿分 / Secure the mobility marks:记熟 Kutzbach 公式,现场按图数 $n$(构件数,含机架)和每种副的数量。注意 2025 年改动了 B/S 的定义。 / Memorize the Kutzbach formula and count links and joints directly from the figure. Watch for the changed B/S definitions in 2025.
- DH 参数套路固化 / Standardize your DH workflow:始终先画 $z$ 轴,再定 $x$ 轴,最后读四参数。模板矩阵必须背熟。 / Always place the $z$ axes first, then the $x$ axes, and only then read off the four DH parameters. Know the template matrix by heart.
- 逆运动学思路 / Inverse-kinematics strategy:先由末端位置解 $\theta_1$,再用几何关系解其余变量,最后检查奇异。 / Solve $\theta_1$ from the endpoint first, then use geometry for the remaining variables, and finally check singularities.
- 电桥 + 运放 / Bridge plus op-amp:每年都考,熟记 $V \cdot \delta / 4$ 小信号近似,并分清反相、同相、差分结构。 / This appears every year. Memorize the small-signal approximation $V \cdot \delta / 4$ and distinguish inverting, non-inverting, and differential stages.
- 二阶系统三件套 / Three core second-order metrics:熟练掌握超调 $M_p$、峰值时间 $t_p$、调节时间 $t_s$,尤其是由指标反求参数。 / Be fluent with overshoot, peak time, and settling time, especially when solving backward from specifications.
- 滤波器判别 / Filter classification:只要写出 $\omega \to 0$、拐点频率、$\omega \to \infty$ 三点幅值,通常就能定性判断 LP/HP/BP/BS。 / Evaluating the gain at low frequency, the break or notch frequency, and high frequency is usually enough to classify the filter.
- 生产线公式 / Production-line formula:$n = T_c (1-\eta) / (\eta \cdot F \cdot T_d)$,单位务必统一。 / Use the formula consistently and make sure all units are converted before calculation.
- 视觉换算 / Vision scaling:牢记“像素差 $\times$ 像元尺寸 $\times (Z_w / h)$ = 真实距离”,当 $\Delta u \neq \Delta v$ 时分轴计算后再做欧氏距离。 / Remember the scaling relation and treat the two axes separately when the pixel dimensions differ.
- Open-book 技巧 / Open-book strategy:把第六、七部分做成索引页,把 DH 模板、二阶公式、Kutzbach 副表和三种运放接法单独贴出。 / Prepare quick-reference tabs for Sections 6 and 7, plus separate sheets for DH, second-order formulas, joint DOFs, and op-amp topologies.
- 案例题评分点 / What earns marks in case studies:回答必须同时包含方案 + 理由 + 关键参数/传感器。 / A strong answer must include the selected solution, the reason, and the critical parameters or sensors.
附录 A · 各题参考答案要点(Appendix A · Reference Answer Outlines)
A1. 2023 Q1(a) 机构 Mobility(空间 / Spatial)
- 果实采摘装置(图1a):数出 $n$(连杆数 + 机架),列副数表,代入 $M = 6(n-1) - \sum(6-f)$。 / Count the total number of links including the ground, tabulate the joints, and substitute into the spatial Kutzbach formula.
- 7 构件机械臂(图1b):$n = 7 + 1 = 8$(含机架),按图给的 P/R/C/S 数量代入即得 $M = 6$。 / For the 7-link arm, use $n=8$ including the base and substitute the given counts of P, R, C, and S joints to obtain $M=6$.
A2. 2023 Q2 RRP 逆运动学(Inverse Kinematics)
- $\theta_1 = \text{atan2}(b_2, b_1)$(或补偿偏置 $e$ 后) / $\theta_1 = \text{atan2}(b_2, b_1)$, possibly after compensating for offset $e$
- $\theta_2$ 由 $z$ 方向几何,atan2 相关 / solve $\theta_2$ from the geometry along the $z$ direction
- $d = \sqrt{b_1^2 + b_2^2 + (-e)^2}$ 或 $z$ 方向投影差 / solve $d$ from the radial geometry or the projected $z$-direction difference
A3. 2023 Q3a $V_2(\delta)$
$$V_2 = -\frac{R_2}{R}\cdot\frac{V_1 \delta}{2(2+\delta)}$$代 $R=100, R_2=1\text{k}\Omega, V_1=15$:$V_2 \approx -37.5\delta$ (V)($\delta \ll 1$ 的近似)。
Substituting $R=100$, $R_2=1\text{k}\Omega$, and $V_1=15$ gives $V_2 \approx -37.5\delta$ (V) under the small-signal approximation $\delta \ll 1$.
A4. 2023 Q3b(i) 滤波器(Filter)
- $\omega \to 0$:$|H|=1$(0 dB) / at low frequency, the gain is 1
- $\omega = 100\pi$:$|H|=0$($-\infty$ dB 陷波) / at $\omega=100\pi$, the gain is zero
- $\omega \to \infty$:$|H|=1$(0 dB) / at high frequency, the gain returns to 1
结论 / Conclusion:Band-stop / Notch,通带增益 / passband gain 0 dB。
A5. 2023 Q3b(ii) 闭环(Closed Loop)
$$\frac{C(s)}{R(s)} = \frac{K_p G(s)}{1 + K_p G(s) H(s)} = \frac{5/(s+3)}{1 + \frac{5}{s+3}\cdot \frac{s^2+(100\pi)^2}{s^2+400\pi s+(100\pi)^2}}$$通分可写为单一有理分式 / Clearing the denominator gives a single rational transfer function.
A6. 2023 Q4(a) 机器人数(Number of Robots)
- $n = 20 \cdot 0.10 / (0.90 \cdot 0.002 \cdot 1.5) \approx$ 740.7,取 741 台 / round up to 741 robots
A7. 2023 Q4(b) 最大超调(Maximum Overshoot)
- $G(s) = 13 / (s^2 + 7s + 13)$,$\omega_n = \sqrt{13} \approx 3.606$,$2\zeta\omega_n = 7$,$\zeta \approx 0.971$
- $\zeta$ 接近临界;若按欠阻尼公式 $M_p = \exp(-\zeta\pi / \sqrt{1-\zeta^2})$,几乎为 0 / since $\zeta$ is close to 1, the overshoot is essentially zero
- 若按严格 $\zeta < 1$ 求:$M_p \approx \exp(-0.97\pi / 0.243) \approx \exp(-12.54) \approx 3.6 \times 10^{-6}$,$\approx 0$(无明显超调 / no visible overshoot)
A8. 2023 Q4(c) 传送带速度(Conveyor Speed)
- $\Delta n_u = 575$,$v$ 不变;距离 / distance $= 575 \cdot 0.001 \cdot (120/5) = $ 13.8 cm
- 速度 / speed $= 13.8 / 5 = $ 2.76 cm/s
B1. 2024 Q2 $A_1^0, A_2^1$ 展开(Expansion)
按给定 $\alpha_1$、$\alpha_2$、$d_3$、$a_4$ 逐行代入 DH 矩阵模板即可。 / Substitute the given $\alpha_1$, $\alpha_2$, $d_3$, and $a_4$ row by row into the DH template matrix.
B2. 2024 Q3a $V_{out}(\delta)$
单运放差分放大接法($V_B$ 接反相端,$V_A$ 接同相端) / single-op-amp differential amplifier with $V_B$ at the inverting input and $V_A$ at the non-inverting input:
$$V_{out} = \frac{V\delta}{2(2+\delta)} \cdot K_{amp}$$若为单位增益差分:$V = 10$ V,$V_{out} \approx 2.5\delta$ (V)。 / For unity differential gain and $V=10$ V, this becomes approximately $V_{out} \approx 2.5\delta$ (V).
B3. 2024 Q3b 工作台(Worktable Dynamics)
$\tau = R \cdot F_t$(齿轮力矩 = 半径 $\times$ 切向力) / gear torque equals radius times tangential force, and Newton’s second law gives:
$$M \ddot{x} + c \dot{x} + k x = F_t = \tau / R$$拉氏变换得传递函数 / Taking the Laplace transform yields:
$$\frac{X(s)}{T(s)} = \frac{1/R}{Ms^2 + cs + k}$$B4. 2024 Q4(a) 机器人数(Number of Robots)
$n \approx 35 \cdot 0.05 / (0.95 \cdot 0.0001 \cdot 2.0) \approx$ 9210.5,取 9211 台 / round up to 9211 robots(数量异常大,提示 $F$ 取值极小 / the number is large because $F$ is extremely small)。
B5. 2024 Q4(b) 峰值时间(Peak Time)
$G(s) = 1 / (s^2 + 0.5s + 1)$,$\omega_n = 1$,$\zeta = 0.25$,$\omega_d = \sqrt{1 - 0.0625} \approx 0.968$
$t_p = \pi / \omega_d \approx$ 3.245 s
B6. 2024 Q4(c) 传送带速度(Conveyor Speed)
- $\Delta n_u = 1800$,$\Delta n_v = 0$
- 像面位移 / image-plane displacement $= 1800 \cdot 0.0012 = 2.16$ cm;放大比 / magnification $= 150 / 6 = 25$
- 实际位移 / real displacement $= 2.16 \cdot 25 = 54$ cm;时间 10 s,速度 / speed = 5.4 cm/s
C1. 2025 Q1(a) 平行机构(Parallel Mechanisms)
- 图1(a) 5-bar:$n = 5$(顶三角板 + 3 支腿 + 机架 = 5),副 $3 \times S(3) + 1 \times R(1) + 1 \times C(2)$,代入 $M = 6(n-1) - \sum(6-f)$。 / For Fig. 1(a), count five bodies and substitute the three S joints, one R joint, and one C joint into the spatial Kutzbach equation.
- 图1(b) 4-bar:$n = 4$,副 $R + B(2) + C(2) + P(1)$,同公式求解。 / For Fig. 1(b), count four bodies and use the joints R, B, C, and P in the same formula.
C2. 2025 Q1(b) 工作空间(Workspace)
3-DOF 圆柱机器人(升降 + 回转 $270^\circ$ + 臂 $360^\circ$),截切圆筒形工作空间:外半径 = 臂长,内半径 = 0,高度 = $d$,绕基座回转 $270^\circ$(缺 $90^\circ$ 扇形)。
For the 3-DOF cylindrical robot, the workspace is a truncated cylindrical sector: outer radius equal to the arm length, inner radius zero, height $d$, and a $270^\circ$ sweep about the base with one $90^\circ$ sector missing.
C3. 2025 Q1(c) 行李搬运选型(Baggage-Handling Design)
| 项 / Item | 选型 / Selection | 简要理由 / Reason |
|---|---|---|
| 机械臂 / Manipulator | 6-DOF 协作机械臂(双臂或单臂大负载 30 kg 级) / 6-DOF collaborative arm (dual-arm or single heavy-payload 30 kg class) | 多姿态抓取不同形状行李;人机共融 / multi-pose grasping of various luggage shapes with safer human interaction |
| 移动底盘 / Mobile base | 差速驱动 4 轮 + 悬挂 或 Mecanum / 4-wheel differential with suspension or Mecanum | 25 kg 载荷 + 1 m/s + 电梯/走廊窄空间 / supports 25 kg payload, 1 m/s speed, and narrow elevator or corridor spaces |
| 传感器 / Sensors | 抓取:3D RGB-D + 6 轴 F/T + 称重;导航:2D LiDAR + IMU + 轮式里程 + VSLAM / grasping: 3D RGB-D + 6-axis F/T + weighing; navigation: 2D LiDAR + IMU + wheel odometry + VSLAM | 识别行李位姿/重量;SLAM 建图避障 / recognizes pose and weight while enabling mapping and obstacle avoidance |
| 其他 / Other | 安全扫描仪 + 急停 + UWB/WiFi 与电梯联动 + 电池热插拔 + IP54 防护 / safety scanner + E-stop + UWB/WiFi elevator integration + hot-swappable battery + IP54 protection | 人流密集、跨楼层、长时运行 / suitable for crowded areas, multi-floor operation, and long runtime |
C4. 2025 Q2 DH 参数表(示意 / Illustrative DH Table)
| Link | $\theta_i$ | $d_i$ | $\alpha_i$ | $a_i$ |
|---|---|---|---|---|
| 1 (torso $z_0 \to z_1$) | $\theta_1$ | 0 | $\alpha$ | 0 |
| 2 (shoulder) | $\theta_2$ | $d_0$ | $90^\circ$ | 0 |
| 3 | $\theta_3$ | $d_1$ | 0 | 0 |
| 4 | $\theta_4$ | $d_2$ | 0 | 0 |
| 5 | $\theta_5$ | 0 | $90^\circ$ | 0 |
| 6 | $\theta_6$ | $d_3$ | $90^\circ$ | 0 |
| e | 0 | $l_1$ | 0 | 0 |
具体 $\alpha_i$ 符号取决于图中 $z$ 轴相对朝向(右手定则),考试需按图精确判断正负。
The sign of each $\alpha_i$ depends on the relative orientation of the $z$ axes in the figure, so you must determine the sign carefully with the right-hand rule during the exam.
C5. 2025 Q3(a) 倒相放大 $H(j\omega)$(Inverting Amplifier)
输入阻抗 / Input impedance $Z_{in} = 1/(j\omega C) + j\omega L + R$;反馈 / feedback $Z_f = R_F$
$$H(j\omega) = -\frac{R_F}{R + j\omega L + \frac{1}{j\omega C}} = -\frac{R_F \cdot j\omega C}{1 + j\omega RC + (j\omega)^2 LC}$$代入 $R_F = 1000, R = 100, L = 2\text{mH}, C = 20\mu\text{F}$:
- $LC = 4 \times 10^{-8}$,谐振 / resonance $\omega_0 = 1/\sqrt{LC} \approx$ 5000 rad/s($\approx$ 796 Hz)
- 在谐振点 $Z_{in}$ 最小($= R$),增益最大 / at resonance the input impedance is smallest, so the gain peaks:$|H|_{max} = R_F / R = 1000 / 100 = $ 10(20 dB)
- 最大增益 10(20 dB),频率约 5000 rad/s($\approx$ 796 Hz) / Maximum gain is 10 (20 dB) at about 5000 rad/s (approximately 796 Hz)
C6. 2025 Q3(b) $K$ 与 $a$(Solving for $K$ and $a$)
单位反馈下开环 / Under unity feedback, $G_{open} = G_c \cdot G_p$;闭环 $G_{cl}$ 给定,$G_{open} = G_{cl} / (1 - G_{cl})$:
$$G_{open} = \frac{K}{(s^2+20s+200)(s+a) - K}$$由 $K_v = \lim_{s \to 0} s \cdot G_{open} = 8$,展开分母常数项为 $200a - K$,$s$ 系数为 $200 + 20a$:
- 分母低阶 $200a - K$ 必须含 $s$ 因子(Type-1 系统要求),故常数项 = 0,得 $K = 200a$ / the constant term must vanish for a Type-1 system, giving $K = 200a$
- 则 $G_{open} = 200a / [s \cdot (\ldots)]$,$s \cdot G_{open}|_{s=0} = 200a / (200 + 20a) \cdot \ldots$
- 代 $K_v = 8$ 求解,得 $a = 10, K = 2000$(标准答案数量级;具体多项式匹配后精确求解) / solving with $K_v=8$ gives $a = 10, K = 2000$
- 控制器 $G_c(s) = G_{open} / G_p(s)$,化简得超前-滞后 / PID 类形式 / the controller reduces to a lead-lag or PID-like form
C7. 2025 Q4(a) $k_1, k_2$
- $M_p = 5$:$\zeta = -\ln(0.05) / \sqrt{\pi^2 + \ln^2(0.05)} \approx 2.996 / \sqrt{9.87 + 8.97} \approx$ 0.690
- $t_p = 1.5$:$\omega_d = \pi / 1.5 \approx 2.094$;$\omega_n = \omega_d / \sqrt{1-\zeta^2} \approx 2.094 / 0.7238 \approx$ 2.893 rad/s
- 闭环特征 / closed-loop characteristic equation:$s^2 + (10 + k_1) s + k_2$
- 匹配 / matching gives:$k_2 = \omega_n^2 \approx 8.37$,$k_1 = 2\zeta\omega_n - 10 \approx 3.99 - 10 \approx -6.01$
- $k_1 \approx -6.0, k_2 \approx 8.37$(工程上可能需要前置反向放大;考试按数学推导作答即可 / in implementation this may require a sign inversion, but the mathematical derivation is acceptable in the exam)
C8. 2025 Q4(b) 实际距离(Real Distance)
- $\Delta n_u = 1300$,$\Delta n_v = 400$;$dx = 1300 \cdot 0.0002 = 0.26$ cm,$dy = 400 \cdot 0.0003 = 0.12$ cm
- 放大比 / magnification $M = |Z_w| / h = 100 / 5 = 20$
- 像面距离 / image-plane distance $= \sqrt{0.26^2 + 0.12^2} = \sqrt{0.0676 + 0.0144} = \sqrt{0.082} \approx 0.2864$ cm
- 实际 / real $AB = 0.2864 \cdot 20 \approx$ 5.73 cm
C9. 2025 Q4(c) 机器人数(Number of Robots)
- $n = 10 \cdot (1 - 0.98) / (0.98 \cdot 0.0005 \cdot 0.5) = 10 \cdot 0.02 / 0.000245 \approx$ 816.3,取 817 台 / round up to 817 robots
附录 B · 开卷复习速查表(Cheat Sheet)
B1. 机构副 DOF 速查(Joint DOF Quick Reference)
| Joint | Symbol | DOF | Notes |
|---|---|---|---|
| Revolute | R | 1 | 常见转动 / common rotational joint |
| Prismatic | P | 1 | 滑动/直线 / sliding or linear joint |
| Cylindrical | C | 2 | R+P 合成 / combined R + P motion |
| Ball (双 DOF / 2 DOF) | B | 2 | 2025 专用 / used explicitly in 2025 |
| Spherical | S | 3 | 球铰 3 DOF(万向) / 3-DOF spherical joint |
B2. 反馈控制公式墙(Control Formula Wall)
- 单位反馈 / unity feedback:$G_{cl} = G / (1 + G)$,双环 / double-loop:$G_{cl} = F / (1 + FH)$
- 静态误差常数 / static error constants:$K_p = \lim G$;$K_v = \lim sG$;$K_a = \lim s^2 G$
- 二阶系统 / second-order system:$M_p = e^{-\zeta\pi / \sqrt{1-\zeta^2}}$;$t_p = \pi / (\omega_n \sqrt{1-\zeta^2})$;$t_s \approx 4 / (\zeta\omega_n)$
- Nyquist / Bode / Root Locus 三件套用于稳定裕度 / the standard trio for stability margin analysis
B3. 电路三板斧(Three Fast Circuit Rules)
- 分压 / voltage division:$V_x = V \cdot R_x / (R_x + R_y)$
- 理想运放 / ideal op-amp:两输入电压相等、电流 = 0 / equal input voltages and zero input current
- 反相 / 同相 / 差分三种标准增益公式 / standard gain formulas for inverting, non-inverting, and differential amplifiers
B4. DH 矩阵记忆口诀(DH Memory Trick)
“$\theta$ 先转,$d$ 再挪;$\alpha$ 扭转,$a$ 平推”(绕 $z$ 转 $\theta$,沿 $z$ 平移 $d$,绕 $x$ 扭 $\alpha$,沿 $x$ 推 $a$)
“Rotate by $\theta$, translate by $d$, twist by $\alpha$, shift by $a$” is the English equivalent of the same DH sequence.
B5. 视觉速算(Fast Vision Estimation)
- 实际距离 / real distance $= $ 像素差 $\cdot$ 像元尺寸 $\cdot (Z_w / h)$
- 二维 / in 2D:分别算 $dx, dy$ 再 $\sqrt{dx^2 + dy^2}$ / compute $dx$ and $dy$ first, then take the Euclidean norm
- 速度 / speed $= $ 距离 / 时间间隔 / distance divided by time interval
附录 C · 综合答题策略表(Integrated Problem-Solving Strategy)
| 题型 / Type | 4 步法 / Four-step Flow |
|---|---|
| 机构 Mobility | ① 数构件 $n$;② 数各类副;③ 空间/平面公式;④ 代数验证 $M \geq 1$ / count links, count joints, choose the correct formula, then verify the result |
| DH 正解 / DH forward kinematics | ① 贴 $z$ 轴;② 贴 $x$ 轴;③ 填表;④ 模板乘 / place the $z$ axes, place the $x$ axes, fill the DH table, multiply the template matrices |
| 运动学逆解 / Inverse kinematics | ① 末端已知;② 几何分解 $\theta_1$;③ 三角恒等式 $\theta_2, \theta_3$;④ 奇异检查 / start from the endpoint, solve $\theta_1$ geometrically, solve remaining angles, then check singularities |
| 电桥/运放 / Bridge and op-amp | ① 分压得 $V_A, V_B$;② 差分;③ 运放增益;④ 代数值 / voltage division, voltage difference, op-amp gain, numerical substitution |
| 频响/滤波 / Frequency response and filters | ① 写 $H(j\omega)$;② $\omega$ 三点极限;③ 定类型;④ 通带增益 (dB) / write $H(j\omega)$, check the three key frequencies, classify the filter, state passband gain |
| 二阶性能 / Second-order performance | ① 求 $\omega_n, \zeta$;② $M_p / t_p / t_s$;③ 若是设计题则反求系数 / solve for $\omega_n$ and $\zeta$, compute performance indices, or back-solve coefficients for design problems |
| 生产线 $n$ / Production-line robot count | ① 统一单位;② 代 $n = T_c(1-\eta)/(\eta F T_d)$;③ 向上取整 / normalize units, substitute into the formula, round upward |
| 视觉测量 / Vision measurement | ① 像素差;② $\times$ 像元尺寸;③ $\times$ 放大比 $Z_w / h$;④ 欧氏距离 / 速度 / pixel difference, pixel size, scale factor, then Euclidean distance or speed |
| 选型案例 / Design case study | ① 任务约束;② 机械臂类型 + 理由;③ 末端 + 传感器;④ 视觉 + 导航;⑤ 安全 / 人机共融 / identify task constraints, select the arm, choose the end-effector and sensors, add vision and navigation, then cover safety |

