EGH413 Advanced Dynamics Equation Sheet
General
                     𝑑𝑟𝑃⁄𝑂                                                𝑑𝑣̅ 𝑃                                 𝜕𝐴
            𝑣̅ 𝑃 =                                            𝑎̅𝑃 =                                      𝐴̇ ̅ =     ̅ × 𝐴̅
                                                                                                                   +𝜔
                      𝑑𝑡                                                   𝑑𝑡                                   𝜕𝑡
                                                                      2
                         𝑛𝑐
   𝑇2 + 𝑉2 = 𝑇1 + 𝑉1 + 𝑊1→2                        𝑊1→2 = ∮ ∑𝐹̅ (𝑟̅ ) ⋅ 𝑑𝑟̅                            𝐻𝑂 = ∑(𝑟̅𝑖 × 𝑚𝑖 𝑣̅𝑖 )
                                                                      1
Position, velocity, and acceleration of a point 𝑷
   System                𝒓̅𝑷/𝑶                        ̅𝑷
                                                      𝒗                                                  ̅𝑷
                                                                                                         𝒂
  Cartesian          𝑥𝑖̂ + 𝑦𝑗̂ + 𝑧𝑘̂          𝑥̇ 𝑖̂ + 𝑦̇ 𝑗̂ + 𝑧̇ 𝑘̂                              𝑥̈ 𝑖̂ + 𝑦̈ 𝑗̂ + 𝑧̈ 𝑘̂
 Cylindrical          𝑅𝑒̅𝑅 + 𝑧𝑒̅𝑧         𝑅̇ 𝑒̅𝑅 + 𝑅𝜃̇𝑒̅𝜃 + 𝑧̇ 𝑒̅𝑧                 (𝑅̈ − 𝑅𝜃̇ 2 )𝑒̅𝑅 + (𝑅𝜃̈ + 2𝑅̇ 𝜃̇)𝑒̅𝜃 + 𝑧̈ 𝑒̅𝑧
                                                                                  [𝑟̈ − 𝑟𝜙̇ 2 − 𝑟𝜃̇ 2 sin2 𝜙]𝑒̅𝑟
                                           𝑟̇ 𝑒̅𝑟 + 𝑟𝜃̇ sin 𝜙 𝑒̅𝜃
  Spherical               𝑟𝑒̅𝑟                                                    +[𝑟𝜙̈ + 2𝑟̇ 𝜙̇ − 𝑟𝜃̇ 2 sin 𝜙 cos 𝜙]𝑒̅𝜙
                                           + 𝑟𝜙̇ 𝑒̅𝜙
                                                                                  +[𝑟𝜃̈ sin 𝜙 + 2𝑟̇ 𝜃̇ sin 𝜙 + 2𝑟𝜙̇𝜃̇ cos 𝜙]𝑒̅𝜃
Rotation Matrices
 Rotation Type                      Rotation Matrix                                       Visualization
                                                1    0                       0
 𝑥-axis                                [𝑅𝑥 ] = [0 cos 𝜃𝑥                   sin 𝜃𝑥 ]
                                                0 − sin 𝜃𝑥                 cos 𝜃𝑥
                                                cos 𝜃𝑦          0 − sin 𝜃𝑦
 𝑦-axis                                [𝑅𝑦 ] = [ 0              1    0 ]
                                                sin 𝜃𝑦          0 cos 𝜃𝑦
                                                 cos 𝜃𝑧           sin 𝜃𝑧          0
 𝑧-axis                                [𝑅𝑧 ] = [− sin 𝜃𝑧          cos 𝜃𝑧          0]
                                                   0                0             1
 Sequence of Body
                                           [𝑅] = [𝑅𝑛 ] … [𝑅2 ][𝑅1 ]
 Fixed Rotations
 Sequence of Space
                                          [𝑅] = [𝑅1 ] … [𝑅𝑛−1 ][𝑅𝑛 ]
 Fixed Rotations
Kinematics an intermediate reference
                                                                                      (𝑥𝑃 )𝑜
                                  Δ𝑟̅𝑃 = Δ𝑟̅𝑂′ + [𝑅]𝑇𝑓 (Δ𝑟̅𝑃 )𝑥𝑦𝑧 + ([𝑅]𝑇𝑓 − [𝑅]𝑇𝑜 ) [(𝑦𝑃 )𝑜 ]
  Displacement
                                                                                      (𝑧𝑃 )𝑜
    Velocity                                 𝑣̅ 𝑃 = 𝑣̅ 𝑂′ + (𝑣̅ 𝑃 )𝑥𝑦𝑧 + 𝜔
                                                                         ̅ × 𝑟̅𝑃/𝑂′
  Acceleration            𝑎̅𝑃 = 𝑎𝑂′ + (𝑎̅𝑃 )𝑥𝑦𝑧 + 𝛼̅ × 𝑟̅𝑃/𝑂′ + 𝜔
                                                                ̅ × (𝜔               ̅ × (𝑣̅ 𝑃 )𝑥𝑦𝑧
                                                                     ̅ × 𝑟̅𝑃/𝑂′ ) + 2𝜔
Equations of Motion (and helpful equations)
  Newton-Euler (when 𝐴 is                                     𝑑𝑃̅                       𝑑𝐻̅𝐴
    an allowable point)                           ∑𝐹𝐺 =           = 𝑚𝑎̅𝐺     ∑𝑀𝐴 =
                                                              𝑑𝑡                         𝑑𝑡
                                   ̅𝐴 = (𝐼𝑥𝑥 𝜔𝑥 − 𝐼𝑥𝑦 𝜔𝑦 − 𝐼𝑥𝑧 𝜔𝑧 )𝑖̂ + (𝐼𝑦𝑦 𝜔𝑦 − 𝐼𝑦𝑥 𝜔𝑥 − 𝐼𝑦𝑧 𝜔𝑧 )𝑗̂
                                   𝐻
    Angular Momentum
                                                  + (𝐼𝑧𝑧 𝜔𝑧 − 𝐼𝑧𝑥 𝜔𝑥 − 𝐼𝑧𝑦 𝜔𝑦 )𝑘̂
                                     𝑑 𝜕ℒ        𝜕ℒ
   Lagrange’s Equations                (      )−     = 𝑄𝑗                                ℒ = 𝑇−𝑉
                                     𝑑𝑡 𝜕𝑞̇ 𝑗    𝜕𝑞𝑗
                                                                               𝑛
   Virtual Work by non-
                                                    𝛿𝑊   𝑛𝑐
                                                              = ∑ 𝐹̅𝑖 ⋅ 𝛿𝑟̅𝑖 = ∑ 𝑄𝑗 𝛿𝑞𝑗
    conservative forces
                                                                   𝑖           𝑗
                                     1              1
                                  𝑇 = 𝑚𝑣̅ 𝐺 ⋅ 𝑣̅ 𝐺 + 𝜔  ̅𝐺
                                                      ̅⋅𝐻                             Centre of Mass
                                     2              2
      Kinetic Energy
                                            1
                                          𝑇= 𝜔  ̅𝑂
                                              ̅⋅𝐻                            Pure rotation about point 𝑂
                                            2
                                        𝑉𝑔𝑟𝑎𝑣𝑖𝑡𝑦 = 𝑚𝑔𝑍                     Gravity potential energy (𝑍 is
                                                                               height above datum)
     Potential Energy
                                                1                          Spring potential energy (Δℓ is
                                       𝑉𝑠𝑝𝑟𝑖𝑛𝑔 = 𝑘𝛥ℓ2                        change from free length)
                                                2
Parallel Axis Transformation
                                  𝐼𝑥 ′ 𝑥 ′ = 𝐼𝑥𝑥 + 𝑚(𝑦𝐵2 + 𝑧𝐵2 )
   Moments of inertia             𝐼𝑦′ 𝑦′ = 𝐼𝑦𝑦 + 𝑚(𝑥𝐵2 + 𝑧𝐵2 )
                                  𝐼𝑧 ′ 𝑧 ′ = 𝐼𝑧𝑧 + 𝑚(𝑥𝐵2 + 𝑦𝐵2 )
                                    𝐼𝑥 ′ 𝑦′ = 𝐼𝑥𝑦 + 𝑚𝑥𝐵 𝑦𝐵
   Products of inertia              𝐼𝑥 ′ 𝑧 ′ = 𝐼𝑥𝑧 + 𝑚𝑥𝐵 𝑧𝐵
                                    𝐼𝑦′ 𝑧 ′ = 𝐼𝑦𝑧 + 𝑚𝑦𝐵 𝑧𝐵