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5 Native 2D first-order Ambisonic recording with an omnidirectional and a figure-of-eight microphone heading front, and a figure-of-eight microphone heading left; photo shown on the right
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This chapter describes the perceptual properties of auditory events, the sound images that we localize in terms of direction and width, when distributing a signal with different amplitudes to one or a couple of loudspeakers. These amplitude differences are what methods for amplitude panning implement, and they are also what mapping of any coinciden...
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... non-coincident or equivalence-stereophonic microphone arrays whose typical playback directions are encoded in Ambisonics. The study by Kurz et al. [12] investigated how recordings by first-order encoding of the soundfield microphone ST450 and the Oktava MK4012 tetrahedral microphone arrays compare to the equivalence-stereophonic ORTF, see Fig. 5.2. In addition, ORTF-like mapping of the Oktava MK4012's frontal signals to the ±30 • directions in 5th order was tested instead of its first-order encoding. Figure 5.3 shows the results of the study in terms of the perceptual attributes localization and spatial depth. It seems that a mixture between ORTF-like 5th-order encoding and ...
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... addition, ORTF-like mapping of the Oktava MK4012's frontal signals to the ±30 • directions in 5th order was tested instead of its first-order encoding. Figure 5.3 shows the results of the study in terms of the perceptual attributes localization and spatial depth. ...
Context 3
... results from the half of the listening experiment done in Graz is analyzed in Fig. 5.4, and the renderers compared were channel-based "ref", a low-passed mono anchor designed to have poor quality "0", a first-order binaural Ambisonic renderer "1c" based on a cube layout with loudspeakers at ±90 • , ±270 • azimuth and ±35.3 • elevation, and MagLS binaural Ambisonic renderers at the orders "1", "2", "3", "4", and "5". ...
Context 4
... formalism is generic and covers simplistic and more complex tasks. It helps understanding that every frequency-independent directional weighting and/or remapping is just re-mixing the Ambisonic signals by a matrix, as in Fig. ...
Context 5
... does not actually require the generic re-mapping and re-weighting formalism from above, yet. The spherical harmonics associated with the Ambisonic channels are shown in Fig. 4.12 and upon closer inspection one recognizes their symmetries, see Fig. 5.5. To mirror the Ambisonic sound scene with regard to planes of symmetry, it is sufficient to sign-invert channels associated with odd-symmetric spherical harmonics as in Fig. 5.6b. Formally, the transform matrix consists of a diagonal matrix T = diag{c} only, with the corresponding sign-change sequence c. 5.5 Ambisonic singals ...
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... from above, yet. The spherical harmonics associated with the Ambisonic channels are shown in Fig. 4.12 and upon closer inspection one recognizes their symmetries, see Fig. 5.5. To mirror the Ambisonic sound scene with regard to planes of symmetry, it is sufficient to sign-invert channels associated with odd-symmetric spherical harmonics as in Fig. 5.6b. Formally, the transform matrix consists of a diagonal matrix T = diag{c} only, with the corresponding sign-change sequence c. 5.5 Ambisonic singals associated with odd symmetric spherical harmonics are sign-inverted to mirror the sound scene. For every Cartesian axis, illustrations above show spherical harmonics up to the third-order, ...
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... mirror the Ambisonic sound scene with regard to planes of symmetry, it is sufficient to sign-invert channels associated with odd-symmetric spherical harmonics as in Fig. 5.6b. Formally, the transform matrix consists of a diagonal matrix T = diag{c} only, with the corresponding sign-change sequence c. 5.5 Ambisonic singals associated with odd symmetric spherical harmonics are sign-inverted to mirror the sound scene. ...
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... can be expressed by a general rotation matrix R consisting of a rotation around z by χ , around y by ϑ, and again around z by ϕ, see Fig. 5.7. This rotation matrix maps every direction θ to a rotated directioñ ...
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... thê L directions of a t ≥ 2N-design is sufficient to sample the harmonics accurately. With the resulting T , rotation is implemented as in Fig. ...
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... Figure 5.8a shows the processing scheme implementing only the non-zero entries of the associated matrix operation T . ...
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... might be most important when mixing is the option to treat the gains of different directions differently: it might be necessary to attenuate directions of uninteresting or disturbing content while boosting directions of a soft target signal. For such a Fig. 5.8 Rotation around z and Ambisonic widening/diffuseness apply simple 2 × 2 rotation matrices/filter matrices to each Ambisonic signal pair χ n,m χ n,−m of the same order n. Note that the order of the input/output channels plotted is not the typical ACN sequence to avoid crossing connections and hereby simplify the diagram manipulation ...
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... signal pair χ n,m χ n,−m of the same order n. Note that the order of the input/output channels plotted is not the typical ACN sequence to avoid crossing connections and hereby simplify the diagram manipulation there is a neutral directional re-mapping˜θmapping˜ mapping˜θ = θ and the transform to define the matrix T that is implemented as in Fig. 5.6a ...
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... with reasonably chosen sizes α and gain ratios g in /g out , the effect will nevertheless produce reasonable results. Figure 5.9 shows a window at azimuth and elevation at 22.5 • with an aperture of 50 • using g in = 1 and g out = 0 and the order of N = 10 with a grid of encoded directions to illustrate the influence of the transformation. ...
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... gets squeezed towards or stretched away from the zenith, or when rotating before and after: towards/from any direction. The integral can be discretized and solved by a suitable t-design as before, only that for lossless operation, the output order˜Norder˜ order˜N must be higher than the input order N. We get a matrix T that is implemented as in Fig. 5.6a is computed ...
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... Figure 5.10 shows warping of the horizontal plane by 20 • downwards, using the test image parameters as with windowing; de-emphasis attenuates widened areas. ...
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... would destroy the directional consistency of the Ambisonics signal. Consequently, dynamic processing should rather affect the levels of all Ambisonic channels in the same way. As it typically contains all the audio signals, it is useful to have the first, omnidirectional Ambisonic channel control the dynamic processor as side-chain input, see Fig. 5.11b. For more information on dynamic processing, the reader is referred to Udo Zölzer's book on Digital audio effects ...
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... apply this technique to Ambisonics, Zotter et al. [32] proposed to employ a dispersive, i.e. frequency-dependent, rotation of the Ambisonic scene around the zaxis as in Eq. (5.8) by the matrix R as described above and in Fig. 5.8b, using 2 × 2 matrices of filters to implement the frequency-dependent argument m ˆ φ cos ...
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... experiment tested the algorithm with both the symmetric impulse responses suggested by Eq. (5.18), and such truncated to their causal q ≥ 0-side, for a listening position at the center of the arrangement (bullet marker) and at 1.25 m shifted to the right, off-center (square marker). Figure 5.12 indicates for the widening algorithm with τ = 1.5 ms that the perceived width saturates above N > 2 at both listening positions. ...
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... in Fig. 5.14, FDNs consists of a matrix A that is orthogonal A T A = I and should mix the signals of the feedback loop well enough to distribute them across all different channels to couple the resonators associated with the different delays τ i . These delays should not have common divisors to avoid pronounced resonance frequencies, and are ...
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... if the room impulse response was recorded by a microphone array as in [38], array processing can be used to estimate the direction of arrival θ DOA (t). For first-order Ambisonic microphone arrays, when suitably band-limited to the frequency range in which the directional mapping is correct, e.g. between 200 Hz and 4 kHz, the vector r DOA of Eq. (A.83) in Appendix A.6.2 yields a suitable estimate˜r Figure 5.16 shows the directional analysis of the first 100 ms of a first-order directional impulse response taken from the openair lib 1 This response was measured in St. Andrew's Church Lyddington, UK (2600 m 3 volume, 11.5 m source-receiver distance) with a Soundfield SPS422B microphone. ...
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... long decays of low frequencies leak into high frequencies, and hereby result in an erroneous spectral brightening of the diffuse tail. Figure 5.17 analyses the behavior in terms of an erroneous increase of reverberation time at high frequencies, especially when using high orders. ...
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... evaluation. Frank's 2016 experiments [44] measuring the area of the sweet spot also investigated the plausibility of reverberation created by their Ambisonically SDM-processed measurements at different order settings, N = 1, 3, 5. For Fig. 5.18b listeners indicated at which distance from the room's center they heard that envelopment began to collapse to the nearest loudspeakers. One can observe that rendering diffuse reverberation for a large audience benefits from a high Ambisonic order. Moreover, experiments in [43] revealed an improvement of the perceived spatial depth ...
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... is called N3D, see Fig. 5.19. This alternating definition is because of a practical choice of the ambix format [49] to avoid high-order channels becoming louder than the zerothorder channel. Also it permits to adapt between channel sequences such as ACN's i = n 2 + n + m or SID's i = n 2 + 2(n − |m|) + (m < 0). It is advisable to use test recordings with the ...
Context 24
... ambix_warping plugin, see Fig. 5.20, implements the above-mentioned warping operations shifting horizontal sounds towards one of the poles, or into both polar directions. Warping can be applied to any other direction than zenith and nadir when placing it between two mutually inverting ambix_rotation or IEM SceneRotator objects that intermediately rotate zenith to ...
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... IEM SceneRotator as the ambix_rotation plugin can be controlled by head tracking and it essential for an immersive headphone-based experience, see Fig. 5.21. Its processing is done as described ...
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... ambix_directional_loudness plugin in Fig. 5.22 implements the abovementioned directional amplitude window in either circular or equi-rectangular spherical shape. Several of these windows can be made, soloed, and remote controlled, each one of which allowing to set a gain for the inside and outside region. This is often useful in practice, when, e.g., reinforcing or attenuating ...
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... be made, soloed, and remote controlled, each one of which allowing to set a gain for the inside and outside region. This is often useful in practice, when, e.g., reinforcing or attenuating desired or undesired signal parts within an Ambisonic scene. To observe the changes made to the Ambisonic scene, the IEM Energy Visualizer can be helpful, see Fig. ...
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... helpful tool. It uses the omnidirectional Ambisonic channel to derive the compression gains (as a side-chain for all other Ambisonic channels). Similarly as the directional_loudness plug-in, the IEM DirectionalCompressor allows to select a window, but this time for setting different dynamic compression within and outside the selected window, see Fig. ...
Context 29
... multichannel mcfx_filter plugin in Fig. 5.25 does not only implement a set of parametric equalizers, a low-and high cut that can be toggled between filter skirts of either 2nd or 4th order, but it also features a real-time spectrum analyzer to observe the changes done to the signal. It is not only practical for Ambisonic purposes, it's just a set of parametric filters that is ...
Context 30
... mcfx_convolver plug-in in Fig. 5.26 is useful for many purposes, also scientific ones, e.g., when testing binaural filters or driving multi-channel arrays with filters, etc. Its configuration files use the jconvolver format that specifies which filter file (typically stored in multi-channel wav files) connects which of its multiple inlets to which of its multiple ...
Context 31
... a cheaper reverberation network, the IEM FDNReverb network described above can be used, see Fig. 5.27. It is not in particular an Ambisonic tool, but can be used in any multi-channel environment. The particularity of the implementation in the IEM suite is that a slow onset can be ...
Context 32
... ambix_widening plug-in in Fig. 5.28 implements the widening by frequencydependent, dispersive rotation of the Ambisonic scene around the z axis as described above. It can also be used to cheaply stylize lateral reflections instead of the IEM RoomEncoder (Fig. 4.36) with time constant settings exceeding 5 ms, or just as a Another tool is quite helpful, the ...
Context 33
... implements the widening by frequencydependent, dispersive rotation of the Ambisonic scene around the z axis as described above. It can also be used to cheaply stylize lateral reflections instead of the IEM RoomEncoder (Fig. 4.36) with time constant settings exceeding 5 ms, or just as a Another tool is quite helpful, the mcfx_gain_delay plug-in in Fig. 5.29. It permits to to solo or mute individual channels, as well as delay and attenuate them differently. What is more and often even more useful: It is invaluably helpful for testing the signal chain, as one can step through the channels with different ...
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... SPARTA plug-in suite by Aalto University provides Ambisonic tools for encoding, decoding on loudspeakers and headphones, as well as visualization. A special feature is the COMPASS decoder plug-in Fig. 5.30 that can increase the spatial resolution of first-, second-, and third-order recordings. Playback can be done either 126 The signal-dependent parametric processing allows to adjust the balance between direct and diffuse sound in each frequency band. In order to suppress artifacts due to the processing, the parametric playback (Par) can ...
Context 35
... Soundfield plug-in by Røde in Fig. 5.31 was originally designed to process the signals from the four cardioid microphone capsules of their Soundfield microphone. However, it also supports first-order Ambisonics as input format. It can decode to various loudspeaker arrangements by placing virtual microphones into the directions of the loudspeakers. The directivity of each ...
Context 36
... non-coincident or equivalence-stereophonic microphone arrays whose typical playback directions are encoded in Ambisonics. The study by Kurz et al. [12] investigated how recordings by first-order encoding of the soundfield microphone ST450 and the Oktava MK4012 tetrahedral microphone arrays compare to the equivalence-stereophonic ORTF, see Fig. 5.2. In addition, ORTF-like mapping of the Oktava MK4012's frontal signals to the ±30 • directions in 5th order was tested instead of its first-order encoding. Figure 5.3 shows the results of the study in terms of the perceptual attributes localization and spatial depth. It seems that a mixture between ORTF-like 5th-order encoding and ...
Context 37
... addition, ORTF-like mapping of the Oktava MK4012's frontal signals to the ±30 • directions in 5th order was tested instead of its first-order encoding. Figure 5.3 shows the results of the study in terms of the perceptual attributes localization and spatial depth. ...
Context 38
... results from the half of the listening experiment done in Graz is analyzed in Fig. 5.4, and the renderers compared were channel-based "ref", a low-passed mono anchor designed to have poor quality "0", a first-order binaural Ambisonic renderer "1c" based on a cube layout with loudspeakers at ±90 • , ±270 • azimuth and ±35.3 • elevation, and MagLS binaural Ambisonic renderers at the orders "1", "2", "3", "4", and "5". ...
Context 39
... formalism is generic and covers simplistic and more complex tasks. It helps understanding that every frequency-independent directional weighting and/or remapping is just re-mixing the Ambisonic signals by a matrix, as in Fig. ...
Context 40
... does not actually require the generic re-mapping and re-weighting formalism from above, yet. The spherical harmonics associated with the Ambisonic channels are shown in Fig. 4.12 and upon closer inspection one recognizes their symmetries, see Fig. 5.5. To mirror the Ambisonic sound scene with regard to planes of symmetry, it is sufficient to sign-invert channels associated with odd-symmetric spherical harmonics as in Fig. 5.6b. Formally, the transform matrix consists of a diagonal matrix T = diag{c} only, with the corresponding sign-change sequence c. 5.5 Ambisonic singals ...
Context 41
... from above, yet. The spherical harmonics associated with the Ambisonic channels are shown in Fig. 4.12 and upon closer inspection one recognizes their symmetries, see Fig. 5.5. To mirror the Ambisonic sound scene with regard to planes of symmetry, it is sufficient to sign-invert channels associated with odd-symmetric spherical harmonics as in Fig. 5.6b. Formally, the transform matrix consists of a diagonal matrix T = diag{c} only, with the corresponding sign-change sequence c. 5.5 Ambisonic singals associated with odd symmetric spherical harmonics are sign-inverted to mirror the sound scene. For every Cartesian axis, illustrations above show spherical harmonics up to the third-order, ...
Context 42
... mirror the Ambisonic sound scene with regard to planes of symmetry, it is sufficient to sign-invert channels associated with odd-symmetric spherical harmonics as in Fig. 5.6b. Formally, the transform matrix consists of a diagonal matrix T = diag{c} only, with the corresponding sign-change sequence c. 5.5 Ambisonic singals associated with odd symmetric spherical harmonics are sign-inverted to mirror the sound scene. ...
Context 43
... can be expressed by a general rotation matrix R consisting of a rotation around z by χ , around y by ϑ, and again around z by ϕ, see Fig. 5.7. This rotation matrix maps every direction θ to a rotated directioñ ...
Context 44
... thê L directions of a t ≥ 2N-design is sufficient to sample the harmonics accurately. With the resulting T , rotation is implemented as in Fig. ...
Context 45
... Figure 5.8a shows the processing scheme implementing only the non-zero entries of the associated matrix operation T . ...
Context 46
... might be most important when mixing is the option to treat the gains of different directions differently: it might be necessary to attenuate directions of uninteresting or disturbing content while boosting directions of a soft target signal. For such a Fig. 5.8 Rotation around z and Ambisonic widening/diffuseness apply simple 2 × 2 rotation matrices/filter matrices to each Ambisonic signal pair χ n,m χ n,−m of the same order n. Note that the order of the input/output channels plotted is not the typical ACN sequence to avoid crossing connections and hereby simplify the diagram manipulation ...
Context 47
... signal pair χ n,m χ n,−m of the same order n. Note that the order of the input/output channels plotted is not the typical ACN sequence to avoid crossing connections and hereby simplify the diagram manipulation there is a neutral directional re-mapping˜θmapping˜ mapping˜θ = θ and the transform to define the matrix T that is implemented as in Fig. 5.6a ...
Context 48
... with reasonably chosen sizes α and gain ratios g in /g out , the effect will nevertheless produce reasonable results. Figure 5.9 shows a window at azimuth and elevation at 22.5 • with an aperture of 50 • using g in = 1 and g out = 0 and the order of N = 10 with a grid of encoded directions to illustrate the influence of the transformation. ...
Context 49
... gets squeezed towards or stretched away from the zenith, or when rotating before and after: towards/from any direction. The integral can be discretized and solved by a suitable t-design as before, only that for lossless operation, the output order˜Norder˜ order˜N must be higher than the input order N. We get a matrix T that is implemented as in Fig. 5.6a is computed ...
Context 50
... Figure 5.10 shows warping of the horizontal plane by 20 • downwards, using the test image parameters as with windowing; de-emphasis attenuates widened areas. ...
Context 51
... would destroy the directional consistency of the Ambisonics signal. Consequently, dynamic processing should rather affect the levels of all Ambisonic channels in the same way. As it typically contains all the audio signals, it is useful to have the first, omnidirectional Ambisonic channel control the dynamic processor as side-chain input, see Fig. 5.11b. For more information on dynamic processing, the reader is referred to Udo Zölzer's book on Digital audio effects ...
Context 52
... apply this technique to Ambisonics, Zotter et al. [32] proposed to employ a dispersive, i.e. frequency-dependent, rotation of the Ambisonic scene around the zaxis as in Eq. (5.8) by the matrix R as described above and in Fig. 5.8b, using 2 × 2 matrices of filters to implement the frequency-dependent argument m ˆ φ cos ...
Context 53
... experiment tested the algorithm with both the symmetric impulse responses suggested by Eq. (5.18), and such truncated to their causal q ≥ 0-side, for a listening position at the center of the arrangement (bullet marker) and at 1.25 m shifted to the right, off-center (square marker). Figure 5.12 indicates for the widening algorithm with τ = 1.5 ms that the perceived width saturates above N > 2 at both listening positions. ...
Context 54
... in Fig. 5.14, FDNs consists of a matrix A that is orthogonal A T A = I and should mix the signals of the feedback loop well enough to distribute them across all different channels to couple the resonators associated with the different delays τ i . These delays should not have common divisors to avoid pronounced resonance frequencies, and are ...
Context 55
... if the room impulse response was recorded by a microphone array as in [38], array processing can be used to estimate the direction of arrival θ DOA (t). For first-order Ambisonic microphone arrays, when suitably band-limited to the frequency range in which the directional mapping is correct, e.g. between 200 Hz and 4 kHz, the vector r DOA of Eq. (A.83) in Appendix A.6.2 yields a suitable estimate˜r Figure 5.16 shows the directional analysis of the first 100 ms of a first-order directional impulse response taken from the openair lib 1 This response was measured in St. Andrew's Church Lyddington, UK (2600 m 3 volume, 11.5 m source-receiver distance) with a Soundfield SPS422B microphone. ...
Context 56
... long decays of low frequencies leak into high frequencies, and hereby result in an erroneous spectral brightening of the diffuse tail. Figure 5.17 analyses the behavior in terms of an erroneous increase of reverberation time at high frequencies, especially when using high orders. ...
Context 57
... evaluation. Frank's 2016 experiments [44] measuring the area of the sweet spot also investigated the plausibility of reverberation created by their Ambisonically SDM-processed measurements at different order settings, N = 1, 3, 5. For Fig. 5.18b listeners indicated at which distance from the room's center they heard that envelopment began to collapse to the nearest loudspeakers. One can observe that rendering diffuse reverberation for a large audience benefits from a high Ambisonic order. Moreover, experiments in [43] revealed an improvement of the perceived spatial depth ...
Context 58
... is called N3D, see Fig. 5.19. This alternating definition is because of a practical choice of the ambix format [49] to avoid high-order channels becoming louder than the zerothorder channel. Also it permits to adapt between channel sequences such as ACN's i = n 2 + n + m or SID's i = n 2 + 2(n − |m|) + (m < 0). It is advisable to use test recordings with the ...
Context 59
... ambix_warping plugin, see Fig. 5.20, implements the above-mentioned warping operations shifting horizontal sounds towards one of the poles, or into both polar directions. Warping can be applied to any other direction than zenith and nadir when placing it between two mutually inverting ambix_rotation or IEM SceneRotator objects that intermediately rotate zenith to ...
Context 60
... IEM SceneRotator as the ambix_rotation plugin can be controlled by head tracking and it essential for an immersive headphone-based experience, see Fig. 5.21. Its processing is done as described ...
Context 61
... ambix_directional_loudness plugin in Fig. 5.22 implements the abovementioned directional amplitude window in either circular or equi-rectangular spherical shape. Several of these windows can be made, soloed, and remote controlled, each one of which allowing to set a gain for the inside and outside region. This is often useful in practice, when, e.g., reinforcing or attenuating ...
Context 62
... be made, soloed, and remote controlled, each one of which allowing to set a gain for the inside and outside region. This is often useful in practice, when, e.g., reinforcing or attenuating desired or undesired signal parts within an Ambisonic scene. To observe the changes made to the Ambisonic scene, the IEM Energy Visualizer can be helpful, see Fig. ...
Context 63
... helpful tool. It uses the omnidirectional Ambisonic channel to derive the compression gains (as a side-chain for all other Ambisonic channels). Similarly as the directional_loudness plug-in, the IEM DirectionalCompressor allows to select a window, but this time for setting different dynamic compression within and outside the selected window, see Fig. ...
Context 64
... multichannel mcfx_filter plugin in Fig. 5.25 does not only implement a set of parametric equalizers, a low-and high cut that can be toggled between filter skirts of either 2nd or 4th order, but it also features a real-time spectrum analyzer to observe the changes done to the signal. It is not only practical for Ambisonic purposes, it's just a set of parametric filters that is ...
Context 65
... mcfx_convolver plug-in in Fig. 5.26 is useful for many purposes, also scientific ones, e.g., when testing binaural filters or driving multi-channel arrays with filters, etc. Its configuration files use the jconvolver format that specifies which filter file (typically stored in multi-channel wav files) connects which of its multiple inlets to which of its multiple ...
Context 66
... a cheaper reverberation network, the IEM FDNReverb network described above can be used, see Fig. 5.27. It is not in particular an Ambisonic tool, but can be used in any multi-channel environment. The particularity of the implementation in the IEM suite is that a slow onset can be ...
Context 67
... ambix_widening plug-in in Fig. 5.28 implements the widening by frequencydependent, dispersive rotation of the Ambisonic scene around the z axis as described above. It can also be used to cheaply stylize lateral reflections instead of the IEM RoomEncoder (Fig. 4.36) with time constant settings exceeding 5 ms, or just as a Another tool is quite helpful, the ...
Context 68
... implements the widening by frequencydependent, dispersive rotation of the Ambisonic scene around the z axis as described above. It can also be used to cheaply stylize lateral reflections instead of the IEM RoomEncoder (Fig. 4.36) with time constant settings exceeding 5 ms, or just as a Another tool is quite helpful, the mcfx_gain_delay plug-in in Fig. 5.29. It permits to to solo or mute individual channels, as well as delay and attenuate them differently. What is more and often even more useful: It is invaluably helpful for testing the signal chain, as one can step through the channels with different ...
Context 69
... SPARTA plug-in suite by Aalto University provides Ambisonic tools for encoding, decoding on loudspeakers and headphones, as well as visualization. A special feature is the COMPASS decoder plug-in Fig. 5.30 that can increase the spatial resolution of first-, second-, and third-order recordings. Playback can be done either 126 The signal-dependent parametric processing allows to adjust the balance between direct and diffuse sound in each frequency band. In order to suppress artifacts due to the processing, the parametric playback (Par) can ...
Context 70
... Soundfield plug-in by Røde in Fig. 5.31 was originally designed to process the signals from the four cardioid microphone capsules of their Soundfield microphone. However, it also supports first-order Ambisonics as input format. It can decode to various loudspeaker arrangements by placing virtual microphones into the directions of the loudspeakers. The directivity of each ...
Citations
... Immersive virtual environments can be used to experience 3D visualizations with the aim of providing a more realistic experience by surrounding users with stimuli such as audio stimuli. Despite research primarily focusing on the spatial fidelity of multi-loudspeaker playback, the overall quality of surround sound playback was found to be largely determined by timbral fidelity (Zotter & Frank, 2019). The animation toolkit in SolidWorks was used to create the motion of robotics by adding motors at each joint of the robot to simulate movements. ...
Manufacturing applications of virtual reality (VR) technology are growing. The challenge is to design, integrate, and evaluate VR simulation for manufacturing Systems that improves the effectiveness of the planning process. In this paper, we discuss the technical infrastructure necessary to design a collaborative virtual manufacturing planning system. We describe the VR system setup and the integration of hardware and software to produce high-fidelity virtual simulation for manufacturing planning purposes. The designing guidelines are demonstrated by a high-fidelity VR simulation of a stamping process. The VR simulation also presents a method of visualizing computer-aided engineering content. Also, this paper assesses the factors that affect overall fidelity of the VR simulation. Objective evaluation of the VR simulation was conducted using the fidelity framework and the scales, whereas the subjective evaluation methods used were VR-simulation-driven data interpretation. The VR simulation was evaluated by a selective sample of 33 senior engineering students using a highly reliable scale (Cronbach’s Alpha = .93) questionnaire that was designed to evaluate functionality, performance, and experience. The results of the subjective evaluation validate the evaluation of objective scales to be high-medium for the VR system used (M = 5.24, M = 5.11) respectively. Significant positive relationships were found between all factors, except distraction, which had a significant negative relationship with fidelity. Overall, the realism and sensory systems factors were found to be the main significant factors affecting the fidelity of the VR system.
